Update README with more TO-DOs

Fix compilation error on UE 5.1

CHANGES.md

@@ -5,6 +5,49 @@ Versions marked as 'unofficial' are labelled only for the needs of this changelo
 Change History
 --------------
 
+Version: 1.22 (2021/04)
+- Fixed potential for initialization fiasco when using delegates container.
+- Fixed bug in code protecting redirecting handles from self-referencing.
+- Fixed cached resource handles getting invalid after reloading texture resources.
+
+Version: 1.21 (2020/07-09)
+Improving stability
+- Fixed a crash in the input handler caused by invalidated by hot-reload instance trying to unregister a delegate.
+- Improved hot-reload stability and support for reloading after recompiling outside of the editor. Both methods should be equally supported and work together.
+- Improved behaviour of delegates when hot-reloading.
+- Changed context index mapping to fix issues with multi-PIE debugging in 4.25.
+- Fixed Linux crash caused by wrong mapping of key codes.
+
+Version: 1.20 (2020/06)
+Transition to IWYU and maintenance:
+- Replaced includes of monolithic headers.
+- Removed explicit PCH and switched to IWYU-style PCH model.
+- Fixed includes to compile without explicit PCH in non-unity mode.
+- Fixed a few issues causing compilation errors in older engine versions.
+- Fixed debug code to compile on platforms using other than char or wchar_t characters.
+- Fixed issues in recently added DPI scaling.
+- Cleaned obsolete and unused code.
+- Replaced custom scope guards with the template provided by the engine.
+
+Version: 1.19 (2020/03-06)
+- Integrated fix for issue with ImGui popup/modal windows not being able to be closed in transparent mouse input mode. 
+- Integrated first version of Adaptive Canvas Size.
+- Added different options to define canvas size, with Adaptive Canvas Size being one of the options (viewport).
+- Added option for DPI scaling.
+
+Version: 1.18 (2020/01)
+- Updated to engine version 4.24.
+- Updated to ImGui version 1.74.
+
+Version: 1.17 (2019/04)
+- Added experimental support for touch input.
+- Integrated fixes allowing to build this as an engine plugin:
+- Added support for sharing with game mouse input.
+- Refactorization of input handling, with changes in SImGuiWidget and compatibility breaking changes in UImGuiInputHandler.
+
+Version: 1.16 (2019/05)
+- Fixed issue with SImGuiLayout blocking mouse input for other Slate widgets, which was introduced by refactorization of widgets (version 1.14, commit c144658f).
+
 Version: 1.15 (2019/04)
 - Added new FImGuiDelegates interface for ImGui debug delegates.
 - Added code preserving delegates during hot-reloading and moving them to a new module.

ImGui.uplugin

@@ -1,7 +1,7 @@
 {
 	"FileVersion": 3,
 	"Version": 1,
-	"VersionName": "1.15",
+	"VersionName": "1.22",
 	"FriendlyName": "ImGui",
 	"Description": "",
 	"Category": "Debug",
@@ -10,14 +10,20 @@
 	"DocsURL": "",
 	"MarketplaceURL": "",
 	"SupportURL": "",
-	"CanContainContent": true,
+	"CanContainContent": false,
 	"IsBetaVersion": false,
 	"Installed": false,
 	"Modules": [
 		{
 			"Name": "ImGui",
-			"Type": "Developer",
+			"Type": "DeveloperTool",
 			"LoadingPhase": "PreDefault"
 		}
+	],
+	"Plugins": [
+		{
+			"Name": "EnhancedInput",
+			"Enabled": true
+		}
 	]
 }

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017-2019 Sebastian Gross
+Copyright (c) 2017-2021 Sebastian Gross
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,90 +1,190 @@
 Unreal ImGui
 ============
-
 [![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE.md)
 
-Unreal ImGui is an Unreal Engine 4 plug-in which integrates [Dear ImGui](https://github.com/ocornut/imgui) framework developed by Omar Cornut.
+Unreal ImGui is an Unreal Engine 5 plug-in that integrates [Dear ImGui](https://github.com/ocornut/imgui) developed by Omar Cornut.
 
-Dear ImGui simplifies and helps with creation of quality visualisation and debugging tools for your Unreal projects.
+Dear ImGui is an immediate-mode graphical user interface library that is very lightweight and easy to use. It can be very useful when creating debugging tools.
 
+:stop_button: Read Me First
+---------------------------
+This is a fork of [https://github.com/benui-dev/UnrealImGui](https://github.com/benui-dev/UnrealImGui), which itself is a fork of the original UnrealImGui project by [https://github.com/segross/UnrealImGui](https://github.com/segross/UnrealImGui).
+
+You can view the original readme.md, please see this link: [UnrealImGui ReadMe.md](https://github.com/benui-dev/UnrealImGui/blob/master/README.md).
+
+Fork Additions/Fixes
+--------------------
+ - Updated Dear ImGui to 1.91.5-docking
+ - Added configurable docking-enabled setting
+
+TO-DO
+-----
+ - [X] Update Dear ImGui to latest 'docking' branch release (which as of writing is 1.91.5-docking)
+ - [ ] Update ImPlot to latest (as of writing is 0.16)
+ - [X] Update input state to use new ImGuiKey API
+ - [ ] Update gamepad navigation to use new ImGuiKey API
+ - [X] Enable docking
+ - [ ] Support full-screen dock space
+ - [ ] Add NetImGui support
 
 Status
 ------
-ImGui version: 1.65
+UnrealImGui Version: 1.22
 
-Supported engine version: 4.22*
+ImGui version: 1.91.5-docking
 
-\* *Plugin has been tested and if necessary updated to compile and work with this engine version. As long as possible I will try to maintain backward compatibility of existing features and possibly but not necessarily when adding new features. Right now it should be at least backward compatible with the engine version 4.15.*
+ImPlot version: v0.13 WIP
 
+Supported Unreal Engine version: 5.4*
 
-About
------
+\* *The original repository and Ben's fork that this project is based on has support for Unreal 4.26 to 5.3. As of writing I am currently using this plugin on Unreal 5.4 with no issues. I cannot guarantee compatibility with versions other than the ones previously listed, so use this plugin with other versions of Unreal at your own risk.* 
 
-This plug-in adds to Unreal project ImGui module. Adding it as as a dependency to other modules enables them to use Dear ImGui framework.
-
-The base aim of the project is to provide a basic integration of Dear ImGui, without imposing any patters how it should be used in projects.
-
-This is a work in progress but it supports key Unreal features, like Multi-PIE sessions etc.
-
-When running Multi-PIE session, each world gets its own ImGui context to draw world specific data. When world update begins contexts are switched automatically, so using ImGui during objects update should be as easy as calling ImGui API functions.
-
-For scenarios where automatic context switching above is not enough I'm planning to add mechanism allowing to explicitly select contexts. After that I plan to add example project, more usability features, better documentation and integration of Remote ImGui which enables using ImGui from a browser and to investigate possibility of opening ImGui for Blueprints.
-
-
-How to use it
+How to Set up
 -------------
+On top of reading the base repository's [How to Set up](https://github.com/segross/UnrealImGui/blob/master/README.md#how-to-set-up) segment, you'll need to add the following line to your `[GameName].Build.cs` file otherwise you'll get linking errors:
 
-To use this plug-in, you will need a C++ Unreal project.
-
-Content of this repository needs to be placed in *Plugins* directory under project's root: */Plugins/ImGui*. After you compile and run you should notice that *ImGui* module is now available.
-
-To use that in other modules you will need to declare it as a public or private dependency in those modules' Build.cs files:
-
-```C#
-PublicDependencyModuleNames.AddRange(new string[] { "ImGui" });
-```
-or
-
-```C#
-PrivateDependencyModuleNames.AddRange(new string[] { "ImGui" });
+```cpp
+// Tell the compiler we want to import the ImPlot symbols when linking against ImGui plugin 
+PrivateDefinitions.Add(string.Format("IMPLOT_API=DLLIMPORT"));
 ```
 
-You should now be able to use ImGui.
+# Additional Knowledge
 
+## Using ImPlot
 
-### Console commands
+It's pretty easy to use ImPlot, it's pretty much the same drill as using Dear ImGui with the UnrealImGui plugin. You can see documentation on how to use ImPlot here: [ImPlot](https://github.com/epezent/implot).
 
-Console support evolved from using console variables to plain variables combined with interface and console commands to toggle them. This means that it is possible to bind keys to those commands (currently only one is supported natively) and call interface functions from user code (also in shipping builds, if needed).
+The only thing you won't need to do is call the `ImPlot::CreateContext()` and `ImPlot::DestroyContext` routines as they're already called when ImGui's context is created within UnrealImGui's guts.
 
-- `ImGui.ToggleInput` - Toggle ImGui input mode (disabled by default). If enabled, input is routed to ImGui and with a few exceptions is consumed. It is possible to assign keyboard short-cut to this command trough ImGui properties panel.
-- `ImGui.ToggleKeyboardNavigation` - Toggle ImGui keyboard navigation feature (disabled by default but will be replaced with configurable setting).
-- `ImGui.ToggleGamepadNavigation` - Toggle ImGui gamepad navigation feature (disabled by default but will be replaced with configurable setting).
-- `ImGui.ToggleDemo` - Toggle visibility of the ImGui demo (disabled by default).
+## Drawing a UTextureRenderTarget2D
 
-### Console variables
+One might want to render viewports into the world in an ImGui window. You can do this pretty simply by generating a `UTextureRenderTarget2D` then assigning that to a `ASceneCapture2D` actor in your world. Here's some sample code for generating an correctly managing the `UTextureRenderTarget2D`:
+```cpp
+void Init()
+{
+    TextureRenderTarget = NewObject<UTextureRenderTarget2D>();
+    if(IsValid(TextureRenderTarget))
+    {
+        TextureRenderTarget->InitAutoFormat(512, 512);
+        TextureRenderTarget->UpdateResourceImmediate(true);
+    }
 
-Self-debug functionality is based on console variable but it will be also replaced by a command available in developer mode.
+    // ... Generate a unique TextureName here
+    // Register this render target as an ImGui interop handled texture
+    ImGuiTextureHandle = FImGuiModule::Get().FindTextureHandle(TextureName);
+    if(!ImGuiTextureHandle.IsValid())
+    {
+        if(IsValid(TextureRenderTarget))
+        {
+            ImGuiTextureHandle = FImGuiModule::Get().RegisterTexture(TextureName, TextureRenderTarget, true);
+        }
+    }
+}
 
-- `ImGui.Debug.Widget` - Show self-debug for the widget that renders ImGui output. 0: disabled (default); 1: enabled.
-Note: this console variable will be replaced with optional toggle command.
+~Class()
+{
+    // Requires releasing to avoid memory leak
+    FImGuiModule::Get().ReleaseTexture(ImGuiTextureHandle);
+}
 
+void Render()
+{
+    // Actually submit the draw command to ImGui to render the quad with the texture
+    if(ImGuiTextureHandle.IsValid())
+    {
+        ImGui::Image(ImGuiTextureHandle.GetTextureId(), {512.f, 512.f});
+    }
+}
+```
 
-### Canvas Control Mode
+Then generating the `ASceneCapture2D`:
+```cpp
+void Init()
+{
+    FActorSpawnParameters SpawnInfo;
+    SceneCapture2D = World->SpawnActor<ASceneCapture2D>(FVector::ZeroVector, FRotator::ZeroRotator, SpawnInfo);
+    SceneCaptureComponent2D->TextureTarget = TextureRenderTarget;
+    SceneCaptureComponent2D->UpdateContent();
 
-Canvas control mode gives a possibility to navigate around ImGui canvas and control which part of it should be visible on the screen. To activate this mode press and hold `Left Shift` + `Left Alt` keys while in ImGui input mode. Leaving ImGui input mode or releasing shortcut keys will deactivate control mode. While in control mode ImGui draws canvas borders and a frame representing part of the ImGui canvas visible after leaving that mode. To control canvas scale, offset and frame use mouse wheel and dragging:
-- *Mouse Wheel* - to zoom in and out (resets to 1 after leaving control mode)
-- *Right Mouse Button* - to drag ImGui canvas/content
-- *Middle Mouse Button* - to drag frame representing part of the ImGui canvas that will be visible after leaving control mode
+    // Need to use this in order to force capture to use tone curve and also set alpha to scene alpha (1)
+    SceneCaptureComponent2D->CaptureSource = ESceneCaptureSource::SCS_FinalToneCurveHDR;
+}
+```
 
+### Troubleshooting
+If you're using a scene capture and your quad is not drawing at all, make sure your scene capture "Capture Source" is set to "Final Color (with tone curve) in Linear sRGB gamut" to avoid alpha being set to 0 (since there's no way to instruct ImGui to ignore alpha without modding the core UnrealImGui plugin).
+
+If you're getting crashes or seg faults during rendering, make sure you're using `UPROPERTY()` on your class variables!
+
+## Adding custom fonts
+### FontAwesome
+Adding custom fonts is fairly simple. As a more complex and more commonly done, we're going to embed and build FontAwesome 6 into the font atlas. First thing you'll need is a binary C version of the FontAwesome font along with the necessary [companion descriptors](https://github.com/juliettef/IconFontCppHeaders/blob/main/IconsFontAwesome6.h). The descriptors are pre-generated, however if you have a new version of FA you wish to use, then use the Python script in that repository. As for the binary C, you'll need to compile Dear ImGui's [binary_to_compressed_c.cpp](https://github.com/ocornut/imgui/blob/master/misc/fonts/binary_to_compressed_c.cpp).
+
+Once you have the necessary files, you'll need to encode your FontAwesome font using the command:
+```
+binary_to_compressed_c.exe -nocompress fa-solid-900.ttf FontAwesomeFont > FontAwesomeFont.h
+```
+The only mandatory field here is `-nocompress` as this instructs the encoder to create an uncompressed binary file (1:1) since currently there's no immediate support for compressed fonts.
+
+Move over your descriptors and your binary C font file to an appropriate location for inclusion in your Unreal Engine project. The following code is how to instruct ImGui to build the font atlas with your FontAwesome font:
+
+```cpp
+#include "FontAwesomeFont.h"
+#include "IconsFontAwesome6.h"
+
+// Add FontAwesome font glyphs from memory
+if(TSharedPtr<ImFontConfig> FAFontConfig = MakeShareable(new ImFontConfig()))
+{
+    static const ImWchar IconRange[] = { ICON_MIN_FA, ICON_MAX_FA, 0 };
+    
+    FAFontConfig->FontDataOwnedByAtlas = false; // Global font data lifetime
+    FAFontConfig->FontData             = (void*)FontAwesomeData; // Declared in binary C .h file
+    FAFontConfig->FontDataSize         = FontAwesomeSize; // Declared in binary C .h file
+    FAFontConfig->SizePixels           = 16;
+    FAFontConfig->MergeMode            = true; // Forces ImGui to place this font into the same atlas as the previous font
+    FAFontConfig->GlyphRanges          = IconRange; // Required; instructs ImGui to use these glyphs
+    FAFontConfig->GlyphMinAdvanceX     = 16.f; // Use for monospaced icons
+    FAFontConfig->PixelSnapH           = true; // Better rendering (align to pixel grid)
+    FAFontConfig->GlyphOffset          = {0, 3}; // Moves icons around, for alignment with general typesets
+
+    FImGuiModule::Get().GetProperties().AddCustomFont("FontAwesome", FAFontConfig);
+    FImGuiModule::Get().RebuildFontAtlas();
+}
+```
+
+That's it. Make sure you execute the above code once at the beginning of the first ImGui frame (or at any point of your framework where the ImGui context has been initialized correctly) and it should build the main atlas with FontAwesome inside it. ImFontConfig lifetime is currently managed via reference counting (`TSharedPtr`).
+
+### Using the icons
+```cpp
+#include "IconsFontAwesome6.h"
+
+void OnPaint()
+{
+    ImGui::Text(ICON_FA_AWARD);
+}
+```
+
+Pretty simple. Building FStrings that incorporate FontAwesome icons however gets a little trickier:
+```cpp
+FString Str = "Hello " + FString(UTF8_TO_TCHAR(ICON_FA_WAVE_SQUARE)) " World";
+ImGui::TextUnformatted(TCHAR_TO_UTF8(*Str));
+```
+
+### More info
+ - [Dear ImGui: Using Fonts](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md)
+ - [IconFontCppHeaders](https://github.com/juliettef/IconFontCppHeaders)
+ - [FontAwesome with general Dear ImGui](https://pixtur.github.io/mkdocs-for-imgui/site/FONTS/)
+
+# Misc
 
 See also
 --------
-
+ - [Fork this project is based on](https://github.com/benui-dev/UnrealImGui)
+ - [Original project by segross](https://github.com/segross/UnrealImGui)
  - [Dear ImGui](https://github.com/ocornut/imgui)
- - [An Introduction to UE4 Plugins](https://wiki.unrealengine.com/An_Introduction_to_UE4_Plugins).
+ - [ImPlot](https://github.com/epezent/implot)
 
 
 License
 -------
-
-Unreal ImGui is licensed under the MIT License, see LICENSE for more information.
+Unreal ImGui (and this fork) is licensed under the MIT License, see LICENSE for more information.

Source/ImGui/ImGui.Build.cs

@@ -23,14 +23,17 @@ public class ImGui : ModuleRules
 		// Enable runtime loader, if you want this module to be automatically loaded in runtime builds (monolithic).
 		bool bEnableRuntimeLoader = true;
 
-#if UE_4_21_OR_LATER
-		PrivatePCHHeaderFile = "Private/ImGuiPrivatePCH.h";
+		PCHUsage = PCHUsageMode.UseExplicitOrSharedPCHs;
+
+#if UE_4_24_OR_LATER
+		bLegacyPublicIncludePaths = false;
+		ShadowVariableWarningLevel = WarningLevel.Error;
+		bTreatAsEngineModule = true;
 #endif
 
 		PublicIncludePaths.AddRange(
 			new string[] {
 				Path.Combine(ModuleDirectory, "../ThirdParty/ImGuiLibrary/Include"),
-				Path.Combine(ModuleDirectory, "../ThirdParty/ImGuiLibrary/Include/misc/stl")
 				// ... add public include paths required here ...
 			}
 			);
@@ -39,7 +42,7 @@ public class ImGui : ModuleRules
 		PrivateIncludePaths.AddRange(
 			new string[] {
 				"ImGui/Private",
-				"ThirdParty/ImGuiLibrary/Private"
+				"ThirdParty/ImGuiLibrary/Private",
 				// ... add other private include paths required here ...
 			}
 			);
@@ -59,6 +62,7 @@ public class ImGui : ModuleRules
 			new string[]
 			{
 				"CoreUObject",
+				"EnhancedInput",
 				"Engine",
 				"InputCore",
 				"Slate",

Source/ImGui/Private/Editor/ImGuiCanvasSizeInfoCustomization.cpp

@@ -0,0 +1,158 @@
+// Distributed under the MIT License (MIT) (see accompanying LICENSE file)
+
+#include "ImGuiCanvasSizeInfoCustomization.h"
+
+#if WITH_EDITOR
+
+#include "ImGuiModuleSettings.h"
+
+#include <PropertyCustomizationHelpers.h>
+
+
+#define LOCTEXT_NAMESPACE "ImGuiEditor"
+
+
+namespace
+{
+	EImGuiCanvasSizeType GetCanvasSizeTypeEnumValue(const TSharedPtr<IPropertyHandle>& TypeHandle)
+	{
+		uint8 ValueAsByte = 0;
+		if (TypeHandle.IsValid())
+		{
+			TypeHandle->GetValue(ValueAsByte);
+		}
+		return static_cast<EImGuiCanvasSizeType>(ValueAsByte);
+	}
+
+	bool IsAny(const TSharedPtr<IPropertyHandle>& TypeHandle, EImGuiCanvasSizeType Value)
+	{
+		return GetCanvasSizeTypeEnumValue(TypeHandle) == Value;
+	}
+
+	template<typename... TRest>
+	bool IsAny(const TSharedPtr<IPropertyHandle>& TypeHandle, EImGuiCanvasSizeType First, TRest... Rest)
+	{
+		return IsAny(TypeHandle, First) || IsAny(TypeHandle, Rest...);
+	}
+
+	float ShowToHeight(bool bShow)
+	{
+		return bShow ? 0.f /* Infinity */ : SMALL_NUMBER;
+	}
+
+	EVisibility ShowToVisibility(bool bShow)
+	{
+		return bShow ? EVisibility::SelfHitTestInvisible : EVisibility::Hidden;
+	}
+}
+
+//----------------------------------------------------------------------------------------------------
+// FImGuiKeyInfoCustomization implementation
+//----------------------------------------------------------------------------------------------------
+
+TSharedRef<IPropertyTypeCustomization> FImGuiCanvasSizeInfoCustomization::MakeInstance()
+{
+	return MakeShareable(new FImGuiCanvasSizeInfoCustomization);
+}
+
+void FImGuiCanvasSizeInfoCustomization::CustomizeHeader(TSharedRef<IPropertyHandle> InStructPropertyHandle, FDetailWidgetRow& HeaderRow, IPropertyTypeCustomizationUtils& StructCustomizationUtils)
+{
+	TSharedPtr<IPropertyHandle> TypeHandle = InStructPropertyHandle->GetChildHandle(GET_MEMBER_NAME_CHECKED(FImGuiCanvasSizeInfo, SizeType));
+	TSharedPtr<IPropertyHandle> WidthHandle = InStructPropertyHandle->GetChildHandle(GET_MEMBER_NAME_CHECKED(FImGuiCanvasSizeInfo, Width));
+	TSharedPtr<IPropertyHandle> HeightHandle = InStructPropertyHandle->GetChildHandle(GET_MEMBER_NAME_CHECKED(FImGuiCanvasSizeInfo, Height));
+	TSharedPtr<IPropertyHandle> ExtendToViewportHandle = InStructPropertyHandle->GetChildHandle(GET_MEMBER_NAME_CHECKED(FImGuiCanvasSizeInfo, bExtendToViewport));
+
+#define ADD_DIMENSION_SLOT(Handle, LPadding) \
+	+ SHorizontalBox::Slot()\
+	.Padding(LPadding, 0.f, 0.f, 0.f)\
+	.HAlign(HAlign_Fill)\
+	.MaxWidth(80.f)\
+	[\
+		SNew(SVerticalBox)\
+		+ SVerticalBox::Slot()\
+		.AutoHeight()\
+		[\
+			Handle->CreatePropertyNameWidget()\
+		]\
+		+ SVerticalBox::Slot()\
+		.HAlign(HAlign_Fill)\
+		.AutoHeight()\
+		[\
+			Handle->CreatePropertyValueWidget()\
+		]\
+	]
+
+	auto SizeRowHeight = TAttribute<float>::Create([TypeHandle]()
+	{
+		return ShowToHeight(IsAny(TypeHandle, EImGuiCanvasSizeType::Custom));
+	});
+
+	auto SizeRowVisibility = TAttribute<EVisibility>::Create([TypeHandle]()
+	{
+		return ShowToVisibility(IsAny(TypeHandle, EImGuiCanvasSizeType::Custom));
+	});
+
+	auto ExtendRowHeight = TAttribute<float>::Create([TypeHandle]()
+	{
+		return ShowToHeight(IsAny(TypeHandle, EImGuiCanvasSizeType::Custom, EImGuiCanvasSizeType::Desktop));
+	});
+
+	auto ExtendRowVisibility = TAttribute<EVisibility>::Create([TypeHandle]()
+	{
+		return ShowToVisibility(IsAny(TypeHandle, EImGuiCanvasSizeType::Custom, EImGuiCanvasSizeType::Desktop));
+	});
+
+	HeaderRow
+	.NameContent()
+	[
+		InStructPropertyHandle->CreatePropertyNameWidget()
+	]
+	.ValueContent()
+	.MinDesiredWidth(168.f)
+	[
+		SNew(SVerticalBox)
+		+ SVerticalBox::Slot()
+		.AutoHeight()
+		[
+			TypeHandle->CreatePropertyValueWidget()
+		]
+		+ SVerticalBox::Slot()
+		.AutoHeight()
+		.MaxHeight(SizeRowHeight)
+		[
+			SNew(SHorizontalBox)
+			.Visibility(SizeRowVisibility)
+			ADD_DIMENSION_SLOT(WidthHandle, 0.f)
+			ADD_DIMENSION_SLOT(HeightHandle, 6.f)
+		]
+		+ SVerticalBox::Slot()
+		.AutoHeight()
+		.MaxHeight(ExtendRowHeight)
+		[
+			SNew(SHorizontalBox)
+			.Visibility(ExtendRowVisibility)
+			+ SHorizontalBox::Slot()
+			.AutoWidth()
+			[
+				ExtendToViewportHandle->CreatePropertyValueWidget()
+			]
+			+ SHorizontalBox::Slot()
+			.Padding(4.f, 0.f, 0.f, 0.f)
+			.AutoWidth()
+			[
+				ExtendToViewportHandle->CreatePropertyNameWidget()
+			]
+		]
+	];
+
+#undef ADD_DIMENSION_SLOT
+}
+
+void FImGuiCanvasSizeInfoCustomization::CustomizeChildren(TSharedRef<IPropertyHandle> InStructPropertyHandle, IDetailChildrenBuilder& StructBuilder, IPropertyTypeCustomizationUtils& StructCustomizationUtils)
+{
+}
+
+
+#undef LOCTEXT_NAMESPACE
+
+#endif // WITH_EDITOR

Source/ImGui/Private/Editor/ImGuiCanvasSizeInfoCustomization.h

@@ -0,0 +1,22 @@
+// Copyright 1998-2018 Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#if WITH_EDITOR
+
+#include <IPropertyTypeCustomization.h>
+#include <PropertyHandle.h>
+
+
+// Property type customization for FImGuiCanvasSizeInfo.
+class FImGuiCanvasSizeInfoCustomization : public IPropertyTypeCustomization
+{
+public:
+	static TSharedRef<IPropertyTypeCustomization> MakeInstance();
+
+	// IPropertyTypeCustomization interface
+	virtual void CustomizeHeader(TSharedRef<IPropertyHandle> InStructPropertyHandle, FDetailWidgetRow& HeaderRow, IPropertyTypeCustomizationUtils& StructCustomizationUtils) override;
+	virtual void CustomizeChildren(TSharedRef<IPropertyHandle> InStructPropertyHandle, IDetailChildrenBuilder& StructBuilder, IPropertyTypeCustomizationUtils& StructCustomizationUtils) override;
+};
+
+#endif // WITH_EDITOR

Source/ImGui/Private/Editor/ImGuiEditor.cpp

@@ -1,15 +1,15 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
-#if WITH_EDITOR
-
 #include "ImGuiEditor.h"
 
+#if WITH_EDITOR
+
+#include "ImGuiCanvasSizeInfoCustomization.h"
 #include "ImGuiKeyInfoCustomization.h"
 #include "ImGuiModuleSettings.h"
 
 #include <ISettingsModule.h>
+#include <Modules/ModuleManager.h>
 
 
 #define LOCTEXT_NAMESPACE "ImGuiEditor"
@@ -69,6 +69,8 @@ void FImGuiEditor::Register()
 		{
 			bCustomPropertyTypeLayoutsRegistered = true;
 
+			PropertyModule->RegisterCustomPropertyTypeLayout("ImGuiCanvasSizeInfo",
+				FOnGetPropertyTypeCustomizationInstance::CreateStatic(&FImGuiCanvasSizeInfoCustomization::MakeInstance));
 			PropertyModule->RegisterCustomPropertyTypeLayout("ImGuiKeyInfo",
 				FOnGetPropertyTypeCustomizationInstance::CreateStatic(&FImGuiKeyInfoCustomization::MakeInstance));
 		}
@@ -93,6 +95,7 @@ void FImGuiEditor::Unregister()
 
 		if (FPropertyEditorModule* PropertyModule = GetPropertyEditorModule())
 		{
+			PropertyModule->UnregisterCustomPropertyTypeLayout("ImGuiCanvasSizeInfo");
 			PropertyModule->UnregisterCustomPropertyTypeLayout("ImGuiKeyInfo");
 		}
 	}

Source/ImGui/Private/Editor/ImGuiEditor.h

@@ -4,6 +4,9 @@
 
 #if WITH_EDITOR
 
+#include <Delegates/IDelegateInstance.h>
+
+
 // Registers module's settings in editor (due to a small size of this code we don't use a separate editor module).
 class FImGuiEditor
 {

Source/ImGui/Private/Editor/ImGuiKeyInfoCustomization.cpp

@@ -1,11 +1,9 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
+#include "ImGuiKeyInfoCustomization.h"
 
 #if WITH_EDITOR
 
-#include "ImGuiKeyInfoCustomization.h"
-
 #include "ImGuiModuleSettings.h"
 
 #include <PropertyCustomizationHelpers.h>
@@ -137,7 +135,7 @@ namespace
 
 namespace InputConstants
 {
-	static const FMargin PropertyPadding(2.0f, 0.0f, 2.0f, 0.0f);
+	static const FMargin PropertyPadding(0.0f, 0.0f, 4.0f, 0.0f);
 }
 
 TSharedRef<IPropertyTypeCustomization> FImGuiKeyInfoCustomization::MakeInstance()

Source/ImGui/Private/Editor/ImGuiKeyInfoCustomization.h

@@ -8,10 +8,6 @@
 #include <PropertyHandle.h>
 
 
-class FDetailWidgetRow;
-class IDetailChildrenBuilder;
-class IPropertyHandle;
-
 // Property type customization for FImGuiKeyInfo.
 class FImGuiKeyInfoCustomization : public IPropertyTypeCustomization
 {

Source/ImGui/Private/ImGuiContextManager.cpp

@@ -1,18 +1,19 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiContextManager.h"
 
 #include "ImGuiDelegatesContainer.h"
 #include "ImGuiImplementation.h"
-#include "Utilities/ScopeGuards.h"
+#include "ImGuiModuleSettings.h"
+#include "ImGuiModule.h"
 #include "Utilities/WorldContext.h"
 #include "Utilities/WorldContextIndex.h"
 
 #include <imgui.h>
 
 
+// TODO: Refactor ImGui Context Manager, to handle different types of worlds.
+
 namespace
 {
 #if WITH_EDITOR
@@ -57,11 +58,13 @@ namespace
 #endif // WITH_EDITOR
 }
 
-FImGuiContextManager::FImGuiContextManager()
+FImGuiContextManager::FImGuiContextManager(FImGuiModuleSettings& InSettings)
+	: Settings(InSettings)
 {
-	unsigned char* Pixels;
-	int Width, Height, Bpp;
-	FontAtlas.GetTexDataAsRGBA32(&Pixels, &Width, &Height, &Bpp);
+	Settings.OnDPIScaleChangedDelegate.AddRaw(this, &FImGuiContextManager::SetDPIScale);
+
+	SetDPIScale(Settings.GetDPIScaleInfo());
+	BuildFontAtlas();
 
 	FWorldDelegates::OnWorldTickStart.AddRaw(this, &FImGuiContextManager::OnWorldTickStart);
 #if ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK
@@ -71,6 +74,8 @@ FImGuiContextManager::FImGuiContextManager()
 
 FImGuiContextManager::~FImGuiContextManager()
 {
+	Settings.OnDPIScaleChangedDelegate.RemoveAll(this);
+
 	// Order matters because contexts can be created during World Tick Start events.
 	FWorldDelegates::OnWorldTickStart.RemoveAll(this);
 #if ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK
@@ -88,7 +93,7 @@ void FImGuiContextManager::Tick(float DeltaSeconds)
 		auto& ContextData = Pair.Value;
 		if (ContextData.CanTick())
 		{
-			ContextData.ContextProxy.Tick(DeltaSeconds);
+			ContextData.ContextProxy->Tick(DeltaSeconds);
 		}
 		else
 		{
@@ -96,13 +101,28 @@ void FImGuiContextManager::Tick(float DeltaSeconds)
 			FImGuiDelegatesContainer::Get().OnWorldDebug(Pair.Key).Clear();
 		}
 	}
+
+	// Once all context tick they should use new fonts and we can release the old resources. Extra countdown is added
+	// wait for contexts that ticked outside of this function, before rebuilding fonts.
+	if (FontResourcesReleaseCountdown > 0 && !--FontResourcesReleaseCountdown)
+	{
+		FontResourcesToRelease.Empty();
+	}
 }
 
+#if ENGINE_COMPATIBILITY_LEGACY_WORLD_ACTOR_TICK
 void FImGuiContextManager::OnWorldTickStart(ELevelTick TickType, float DeltaSeconds)
 {
-	if (GWorld)
+	OnWorldTickStart(GWorld, TickType, DeltaSeconds);
+}
+#endif
+
+void FImGuiContextManager::OnWorldTickStart(UWorld* World, ELevelTick TickType, float DeltaSeconds)
+{
+	if (World && (World->WorldType == EWorldType::Game || World->WorldType == EWorldType::PIE
+		|| World->WorldType == EWorldType::Editor))
 	{
-		FImGuiContextProxy& ContextProxy = GetWorldContextProxy(*GWorld);
+		FImGuiContextProxy& ContextProxy = GetWorldContextProxy(*World);
 
 		// Set as current, so we have right context ready when updating world objects.
 		ContextProxy.SetAsCurrent();
@@ -117,7 +137,11 @@ void FImGuiContextManager::OnWorldTickStart(ELevelTick TickType, float DeltaSeco
 #if ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK
 void FImGuiContextManager::OnWorldPostActorTick(UWorld* World, ELevelTick TickType, float DeltaSeconds)
 {
-	GetWorldContextProxy(*GWorld).DrawDebug();
+	if (World && (World->WorldType == EWorldType::Game || World->WorldType == EWorldType::PIE
+		|| World->WorldType == EWorldType::Editor))
+	{
+		GetWorldContextProxy(*World).DrawDebug();
+	}
 }
 #endif // ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK
 
@@ -128,8 +152,8 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetEditorContextData()
 
 	if (UNLIKELY(!Data))
 	{
-		Data = &Contexts.Emplace(Utilities::EDITOR_CONTEXT_INDEX, FContextData{ GetEditorContextName(), Utilities::EDITOR_CONTEXT_INDEX, DrawMultiContextEvent, FontAtlas, -1 });
-		ContextProxyCreatedEvent.Broadcast(Utilities::EDITOR_CONTEXT_INDEX, Data->ContextProxy);
+		Data = &Contexts.Emplace(Utilities::EDITOR_CONTEXT_INDEX, FContextData{ GetEditorContextName(), Utilities::EDITOR_CONTEXT_INDEX, FontAtlas, DPIScale, -1 });
+		OnContextProxyCreated.Broadcast(Utilities::EDITOR_CONTEXT_INDEX, *Data->ContextProxy);
 	}
 
 	return *Data;
@@ -143,8 +167,8 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetStandaloneWorldCont
 
 	if (UNLIKELY(!Data))
 	{
-		Data = &Contexts.Emplace(Utilities::STANDALONE_GAME_CONTEXT_INDEX, FContextData{ GetWorldContextName(), Utilities::STANDALONE_GAME_CONTEXT_INDEX, DrawMultiContextEvent, FontAtlas });
-		ContextProxyCreatedEvent.Broadcast(Utilities::STANDALONE_GAME_CONTEXT_INDEX, Data->ContextProxy);
+		Data = &Contexts.Emplace(Utilities::STANDALONE_GAME_CONTEXT_INDEX, FContextData{ GetWorldContextName(), Utilities::STANDALONE_GAME_CONTEXT_INDEX, FontAtlas, DPIScale });
+		OnContextProxyCreated.Broadcast(Utilities::STANDALONE_GAME_CONTEXT_INDEX, *Data->ContextProxy);
 	}
 
 	return *Data;
@@ -156,7 +180,8 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetWorldContextData(co
 	using namespace Utilities;
 
 #if WITH_EDITOR
-	if (World.WorldType == EWorldType::Editor)
+	// Default to editor context for anything other than a game world.
+	if (World.WorldType != EWorldType::Game && World.WorldType != EWorldType::PIE)
 	{
 		if (OutIndex)
 		{
@@ -184,8 +209,8 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetWorldContextData(co
 #if WITH_EDITOR
 	if (UNLIKELY(!Data))
 	{
-		Data = &Contexts.Emplace(Index, FContextData{ GetWorldContextName(World), Index, DrawMultiContextEvent, FontAtlas, WorldContext->PIEInstance });
-		ContextProxyCreatedEvent.Broadcast(Index, Data->ContextProxy);
+		Data = &Contexts.Emplace(Index, FContextData{ GetWorldContextName(World), Index, FontAtlas, DPIScale, WorldContext->PIEInstance });
+		OnContextProxyCreated.Broadcast(Index, *Data->ContextProxy);
 	}
 	else
 	{
@@ -195,8 +220,8 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetWorldContextData(co
 #else
 	if (UNLIKELY(!Data))
 	{
-		Data = &Contexts.Emplace(Index, FContextData{ GetWorldContextName(World), Index, DrawMultiContextEvent, FontAtlas });
-		ContextProxyCreatedEvent.Broadcast(Index, Data->ContextProxy);
+		Data = &Contexts.Emplace(Index, FContextData{ GetWorldContextName(World), Index, FontAtlas, DPIScale });
+		OnContextProxyCreated.Broadcast(Index, *Data->ContextProxy);
 	}
 #endif
 
@@ -206,3 +231,73 @@ FImGuiContextManager::FContextData& FImGuiContextManager::GetWorldContextData(co
 	}
 	return *Data;
 }
+
+void FImGuiContextManager::SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo)
+{
+	const float Scale = ScaleInfo.GetImGuiScale();
+	if (DPIScale != Scale)
+	{
+		DPIScale = Scale;
+
+		// Only rebuild font atlas if it is already built. Otherwise allow the other logic to pick a moment.
+		if (FontAtlas.IsBuilt())
+		{
+			RebuildFontAtlas();
+		}
+
+		for (auto& Pair : Contexts)
+		{
+			if (Pair.Value.ContextProxy)
+			{
+				Pair.Value.ContextProxy->SetDPIScale(DPIScale);
+			}
+		}
+	}
+}
+
+void FImGuiContextManager::BuildFontAtlas(const TMap<FName, TSharedPtr<ImFontConfig>>& CustomFontConfigs)
+{
+	if (!FontAtlas.IsBuilt())
+	{
+		ImFontConfig FontConfig = {};
+		FontConfig.SizePixels = FMath::RoundFromZero(13.f * DPIScale);
+		FontAtlas.AddFontDefault(&FontConfig);
+
+		// Build custom fonts
+		for (const TPair<FName, TSharedPtr<ImFontConfig>>& CustomFontPair : CustomFontConfigs)
+		{
+			FName CustomFontName = CustomFontPair.Key;
+			TSharedPtr<ImFontConfig> CustomFontConfig = CustomFontPair.Value;
+
+			// Set font name for debugging
+			if (CustomFontConfig.IsValid())
+			{
+				strcpy_s(CustomFontConfig->Name, 40, TCHAR_TO_ANSI(*CustomFontName.ToString()));
+			}
+		
+			FontAtlas.AddFont(CustomFontConfig.Get());
+		}
+
+		unsigned char* Pixels;
+		int Width, Height, Bpp;
+		FontAtlas.GetTexDataAsRGBA32(&Pixels, &Width, &Height, &Bpp);
+
+		OnFontAtlasBuilt.Broadcast();
+	}
+}
+
+void FImGuiContextManager::RebuildFontAtlas()
+{
+	if (FontAtlas.IsBuilt())
+	{
+		// Keep the old resources alive for a few frames to give all contexts a chance to bind to new ones.
+		FontResourcesToRelease.Add(TUniquePtr<ImFontAtlas>(new ImFontAtlas()));
+		Swap(*FontResourcesToRelease.Last(), FontAtlas);
+
+		// Typically, one frame should be enough but since we allow for custom ticking, we need at least to frames to
+		// wait for contexts that already ticked and will not do that before the end of the next tick of this manager.
+		FontResourcesReleaseCountdown = 3;
+	}
+
+	BuildFontAtlas(FImGuiModule::Get().GetProperties().GetCustomFonts());
+}

Source/ImGui/Private/ImGuiContextManager.h

@@ -3,8 +3,12 @@
 #pragma once
 
 #include "ImGuiContextProxy.h"
+#include "VersionCompatibility.h"
 
 
+class FImGuiModuleSettings;
+struct FImGuiDPIScaleInfo;
+
 // TODO: It might be useful to broadcast FContextProxyCreatedDelegate to users, to support similar cases to our ImGui
 // demo, but we would need to remove from that interface internal classes.
 
@@ -18,7 +22,7 @@ class FImGuiContextManager
 {
 public:
 
-	FImGuiContextManager();
+	FImGuiContextManager(FImGuiModuleSettings& InSettings);
 
 	FImGuiContextManager(const FImGuiContextManager&) = delete;
 	FImGuiContextManager& operator=(const FImGuiContextManager&) = delete;
@@ -31,74 +35,59 @@ public:
 	ImFontAtlas& GetFontAtlas() { return FontAtlas; }
 	const ImFontAtlas& GetFontAtlas() const { return FontAtlas; }
 
-
 #if WITH_EDITOR
 	// Get or create editor ImGui context proxy.
-	FORCEINLINE FImGuiContextProxy& GetEditorContextProxy() { return GetEditorContextData().ContextProxy; }
+	FORCEINLINE FImGuiContextProxy& GetEditorContextProxy() { return *GetEditorContextData().ContextProxy; }
 #endif
 
 #if !WITH_EDITOR
 	// Get or create standalone game ImGui context proxy.
-	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy() { return GetStandaloneWorldContextData().ContextProxy; }
+	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy() { return *GetStandaloneWorldContextData().ContextProxy; }
 #endif
 
 	// Get or create ImGui context proxy for given world.
-	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy(const UWorld& World) { return GetWorldContextData(World).ContextProxy; }
+	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy(const UWorld& World) { return *GetWorldContextData(World).ContextProxy; }
 
 	// Get or create ImGui context proxy for given world. Additionally get context index for that proxy.
-	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy(const UWorld& World, int32& OutContextIndex) { return GetWorldContextData(World, &OutContextIndex).ContextProxy; }
+	FORCEINLINE FImGuiContextProxy& GetWorldContextProxy(const UWorld& World, int32& OutContextIndex) { return *GetWorldContextData(World, &OutContextIndex).ContextProxy; }
 
 	// Get context proxy by index, or null if context with that index doesn't exist.
 	FORCEINLINE FImGuiContextProxy* GetContextProxy(int32 ContextIndex)
 	{
 		FContextData* Data = Contexts.Find(ContextIndex);
-		return Data ? &(Data->ContextProxy) : nullptr;
+		return Data ? Data->ContextProxy.Get() : nullptr;
 	}
 
-	// Delegate called for all contexts in manager, right after calling context specific draw event. Allows listeners
-	// draw the same content to multiple contexts.
-	FSimpleMulticastDelegate& OnDrawMultiContext() { return DrawMultiContextEvent; }
+	// Delegate called when a new context proxy is created.
+	FContextProxyCreatedDelegate OnContextProxyCreated;
 
-	// Delegate called when new context proxy is created.
-	FContextProxyCreatedDelegate& OnContextProxyCreated() { return ContextProxyCreatedEvent; }
+	// Delegate called after font atlas is built.
+	FSimpleMulticastDelegate OnFontAtlasBuilt;
 
 	void Tick(float DeltaSeconds);
 
-private:
+	void RebuildFontAtlas();
 
-#if WITH_EDITOR
+private:
 
 	struct FContextData
 	{
-		FContextData(const FString& ContextName, int32 ContextIndex, FSimpleMulticastDelegate& SharedDrawEvent, ImFontAtlas& FontAtlas, int32 InPIEInstance = -1)
+		FContextData(const FString& ContextName, int32 ContextIndex, ImFontAtlas& FontAtlas, float DPIScale, int32 InPIEInstance = -1)
 			: PIEInstance(InPIEInstance)
-			, ContextProxy(ContextName, ContextIndex, &SharedDrawEvent, &FontAtlas)
+			, ContextProxy(new FImGuiContextProxy(ContextName, ContextIndex, &FontAtlas, DPIScale))
 		{
 		}
 
 		FORCEINLINE bool CanTick() const { return PIEInstance < 0 || GEngine->GetWorldContextFromPIEInstance(PIEInstance); }
 
 		int32 PIEInstance = -1;
-		FImGuiContextProxy ContextProxy;
+		TUniquePtr<FImGuiContextProxy> ContextProxy;
 	};
 
-#else
-
-	struct FContextData
-	{
-		FContextData(const FString& ContextName, int32 ContextIndex, FSimpleMulticastDelegate& SharedDrawEvent, ImFontAtlas& FontAtlas)
-			: ContextProxy(ContextName, ContextIndex, &SharedDrawEvent, &FontAtlas)
-		{
-		}
-
-		FORCEINLINE bool CanTick() const { return true; }
-
-		FImGuiContextProxy ContextProxy;
-	};
-
-#endif // WITH_EDITOR
-
+#if ENGINE_COMPATIBILITY_LEGACY_WORLD_ACTOR_TICK
 	void OnWorldTickStart(ELevelTick TickType, float DeltaSeconds);
+#endif
+	void OnWorldTickStart(UWorld* World, ELevelTick TickType, float DeltaSeconds);
 
 #if ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK
 	void OnWorldPostActorTick(UWorld* World, ELevelTick TickType, float DeltaSeconds);
@@ -114,11 +103,16 @@ private:
 
 	FContextData& GetWorldContextData(const UWorld& World, int32* OutContextIndex = nullptr);
 
+	void SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo);
+	void BuildFontAtlas(const TMap<FName, TSharedPtr<ImFontConfig>>& CustomFontConfigs = {});
+
 	TMap<int32, FContextData> Contexts;
 
-	FSimpleMulticastDelegate DrawMultiContextEvent;
-
-	FContextProxyCreatedDelegate ContextProxyCreatedEvent;
-
 	ImFontAtlas FontAtlas;
+	TArray<TUniquePtr<ImFontAtlas>> FontResourcesToRelease;
+
+	FImGuiModuleSettings& Settings;
+
+	float DPIScale = -1.f;
+	int32 FontResourcesReleaseCountdown = 0;
 };

Source/ImGui/Private/ImGuiContextProxy.cpp

@@ -1,14 +1,15 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiContextProxy.h"
 
 #include "ImGuiDelegatesContainer.h"
 #include "ImGuiImplementation.h"
 #include "ImGuiInteroperability.h"
+#include "Utilities/Arrays.h"
+#include "VersionCompatibility.h"
 
-#include <Runtime/Launch/Resources/Version.h>
+#include <GenericPlatform/GenericPlatformFile.h>
+#include <Misc/Paths.h>
 
 
 static constexpr float DEFAULT_CANVAS_WIDTH = 3840.f;
@@ -38,29 +39,47 @@ namespace
 		static FString SaveDirectory = GetSaveDirectory();
 		return FPaths::Combine(SaveDirectory, Name + TEXT(".ini"));
 	}
-}
 
-FImGuiContextProxy::FImGuiContextPtr::~FImGuiContextPtr()
-{
-	if (Context)
+	struct FGuardCurrentContext
 	{
-		// Setting this as a current context. is still required in the current framework version to properly shutdown
-		// and save data.
-		ImGui::SetCurrentContext(Context);
+		FGuardCurrentContext()
+			: OldContext(ImGui::GetCurrentContext())
+		{
+		}
 
-		// Save context data and destroy.
-		ImGui::DestroyContext(Context);
-	}
+		~FGuardCurrentContext()
+		{
+			if (bRestore)
+			{
+				ImGui::SetCurrentContext(OldContext);
+			}
+		}
+
+		FGuardCurrentContext(FGuardCurrentContext&& Other)
+			: OldContext(MoveTemp(Other.OldContext))
+		{
+			Other.bRestore = false;
+		}
+
+		FGuardCurrentContext& operator=(FGuardCurrentContext&&) = delete;
+
+		FGuardCurrentContext(const FGuardCurrentContext&) = delete;
+		FGuardCurrentContext& operator=(const FGuardCurrentContext&) = delete;
+
+	private:
+
+		ImGuiContext* OldContext = nullptr;
+		bool bRestore = true;
+	};
 }
 
-FImGuiContextProxy::FImGuiContextProxy(const FString& InName, int32 InContextIndex, FSimpleMulticastDelegate* InSharedDrawEvent, ImFontAtlas* InFontAtlas)
+FImGuiContextProxy::FImGuiContextProxy(const FString& InName, int32 InContextIndex, ImFontAtlas* InFontAtlas, float InDPIScale)
 	: Name(InName)
 	, ContextIndex(InContextIndex)
-	, SharedDrawEvent(InSharedDrawEvent)
 	, IniFilename(TCHAR_TO_ANSI(*GetIniFile(InName)))
 {
 	// Create context.
-	Context = FImGuiContextPtr(ImGui::CreateContext(InFontAtlas));
+	Context = ImGui::CreateContext(InFontAtlas);
 
 	// Set this context in ImGui for initialization (any allocations will be tracked in this context).
 	SetAsCurrent();
@@ -71,9 +90,12 @@ FImGuiContextProxy::FImGuiContextProxy(const FString& InName, int32 InContextInd
 	// Set session data storage.
 	IO.IniFilename = IniFilename.c_str();
 
-	// Use pre-defined canvas size.
-	IO.DisplaySize = { DEFAULT_CANVAS_WIDTH, DEFAULT_CANVAS_HEIGHT };
-	DisplaySize = ImGuiInterops::ToVector2D(IO.DisplaySize);
+	// Start with the default canvas size.
+	ResetDisplaySize();
+	IO.DisplaySize = {(float)DisplaySize.X, (float)DisplaySize.Y};
+
+	// Set the initial DPI scale.
+	SetDPIScale(InDPIScale);
 
 	// Initialize key mapping, so context can correctly interpret input state.
 	ImGuiInterops::SetUnrealKeyMap(IO);
@@ -83,6 +105,39 @@ FImGuiContextProxy::FImGuiContextProxy(const FString& InName, int32 InContextInd
 	BeginFrame();
 }
 
+FImGuiContextProxy::~FImGuiContextProxy()
+{
+	if (Context)
+	{
+		// It seems that to properly shutdown context we need to set it as the current one (at least in this framework
+		// version), even though we can pass it to the destroy function.
+		SetAsCurrent();
+
+		// Save context data and destroy.
+		ImGui::DestroyContext(Context);
+	}
+}
+
+void FImGuiContextProxy::ResetDisplaySize()
+{
+	DisplaySize = { DEFAULT_CANVAS_WIDTH, DEFAULT_CANVAS_HEIGHT };
+}
+
+void FImGuiContextProxy::SetDPIScale(float Scale)
+{
+	if (DPIScale != Scale)
+	{
+		DPIScale = Scale;
+
+		ImGuiStyle NewStyle = ImGuiStyle();
+		NewStyle.ScaleAllSizes(Scale);
+
+		FGuardCurrentContext GuardContext;
+		SetAsCurrent();
+		ImGui::GetStyle() = MoveTemp(NewStyle);
+	}
+}
+
 void FImGuiContextProxy::DrawEarlyDebug()
 {
 	if (bIsFrameStarted && !bIsDrawEarlyDebugCalled)
@@ -133,14 +188,16 @@ void FImGuiContextProxy::Tick(float DeltaSeconds)
 			EndFrame();
 		}
 
-		// Update context information (some data, like mouse cursor, may be cleaned in new frame, so we should collect it
-		// beforehand).
+		// Update context information (some data need to be collected before starting a new frame while some other data
+		// may need to be collected after).
 		bHasActiveItem = ImGui::IsAnyItemActive();
 		MouseCursor = ImGuiInterops::ToSlateMouseCursor(ImGui::GetMouseCursor());
-		DisplaySize = ImGuiInterops::ToVector2D(ImGui::GetIO().DisplaySize);
 
 		// Begin a new frame and set the context back to a state in which it allows to draw controls.
 		BeginFrame(DeltaSeconds);
+
+		// Update remaining context information.
+		bWantsMouseCapture = ImGui::GetIO().WantCaptureMouse;
 	}
 }
 
@@ -151,10 +208,10 @@ void FImGuiContextProxy::BeginFrame(float DeltaTime)
 		ImGuiIO& IO = ImGui::GetIO();
 		IO.DeltaTime = DeltaTime;
 
-		if (InputState)
-		{
-			ImGuiInterops::CopyInput(IO, *InputState);
-		}
+		ImGuiInterops::CopyInput(IO, InputState);
+		InputState.ClearUpdateState();
+
+		IO.DisplaySize = { (float)DisplaySize.X, (float)DisplaySize.Y };
 
 		ImGui::NewFrame();
 
@@ -237,11 +294,6 @@ void FImGuiContextProxy::BroadcastWorldDebug()
 
 void FImGuiContextProxy::BroadcastMultiContextDebug()
 {
-	if (SharedDrawEvent && SharedDrawEvent->IsBound())
-	{
-		SharedDrawEvent->Broadcast();
-	}
-
 	FSimpleMulticastDelegate& MultiContextDebugEvent = FImGuiDelegatesContainer::Get().OnMultiContextDebug();
 	if (MultiContextDebugEvent.IsBound())
 	{

Source/ImGui/Private/ImGuiContextProxy.h

@@ -3,53 +3,30 @@
 #pragma once
 
 #include "ImGuiDrawData.h"
-
+#include "ImGuiInputState.h"
 #include "Utilities/WorldContextIndex.h"
 
-#include <ICursor.h>
+#include <GenericPlatform/ICursor.h>
 
 #include <imgui.h>
 
 #include <string>
 
 
-class FImGuiInputState;
-
 // Represents a single ImGui context. All the context updates should be done through this proxy. During update it
 // broadcasts draw events to allow listeners draw their controls. After update it stores draw data.
 class FImGuiContextProxy
 {
-	class FImGuiContextPtr
-	{
-	public:
-
-		FImGuiContextPtr() = default;
-		FImGuiContextPtr(ImGuiContext* InContext) : Context(InContext) {}
-
-		FImGuiContextPtr(const FImGuiContextPtr&) = delete;
-		FImGuiContextPtr& operator=(const FImGuiContextPtr&) = delete;
-
-		FImGuiContextPtr(FImGuiContextPtr&& Other) : Context(Other.Context) { Other.Context = nullptr; }
-		FImGuiContextPtr& operator=(FImGuiContextPtr&& Other) { std::swap(Context, Other.Context); return *this; }
-
-		~FImGuiContextPtr();
-
-		ImGuiContext* Get() const { return Context; }
-
-	private:
-
-		ImGuiContext* Context = nullptr;
-	};
-
 public:
 
-	FImGuiContextProxy(const FString& Name, int32 InContextIndex, FSimpleMulticastDelegate* InSharedDrawEvent, ImFontAtlas* InFontAtlas);
+	FImGuiContextProxy(const FString& Name, int32 InContextIndex, ImFontAtlas* InFontAtlas, float InDPIScale);
+	~FImGuiContextProxy();
 
 	FImGuiContextProxy(const FImGuiContextProxy&) = delete;
 	FImGuiContextProxy& operator=(const FImGuiContextProxy&) = delete;
 
-	FImGuiContextProxy(FImGuiContextProxy&&) = default;
-	FImGuiContextProxy& operator=(FImGuiContextProxy&&) = default;
+	FImGuiContextProxy(FImGuiContextProxy&&) = delete;
+	FImGuiContextProxy& operator=(FImGuiContextProxy&&) = delete;
 
 	// Get the name of this context.
 	const FString& GetName() const { return Name; }
@@ -58,30 +35,41 @@ public:
 	const TArray<FImGuiDrawList>& GetDrawData() const { return DrawLists; }
 
 	// Get input state used by this context.
-	const FImGuiInputState* GetInputState() const { return InputState; }
-
-	// Set input state to be used by this context.
-	void SetInputState(const FImGuiInputState* SourceInputState) { InputState = SourceInputState; }
-
-	// If context is currently using input state to remove then remove that binding.
-	void RemoveInputState(const FImGuiInputState* InputStateToRemove) { if (InputState == InputStateToRemove) InputState = nullptr; }
+	FImGuiInputState& GetInputState() { return InputState; }
+	const FImGuiInputState& GetInputState() const { return InputState; }
 
 	// Is this context the current ImGui context.
-	bool IsCurrentContext() const { return ImGui::GetCurrentContext() == Context.Get(); }
+	bool IsCurrentContext() const { return ImGui::GetCurrentContext() == Context; }
 
 	// Set this context as current ImGui context.
-	void SetAsCurrent() { ImGui::SetCurrentContext(Context.Get()); }
+	void SetAsCurrent() { ImGui::SetCurrentContext(Context); }
 
-	// Context display size (read once per frame during context update and cached here for easy access).
+	// Get the desired context display size.
 	const FVector2D& GetDisplaySize() const { return DisplaySize; }
 
-	// Whether this context has an active item (read once per frame during context update and cached here for easy access).
+	// Set the desired context display size.
+	void SetDisplaySize(const FVector2D& Size) { DisplaySize = Size; }
+
+	// Reset the desired context display size to default size.
+	void ResetDisplaySize();
+
+	// Get the DPI scale set for this context.
+	float GetDPIScale() const { return DPIScale; }
+
+	// Set the DPI scale for this context.
+	void SetDPIScale(float Scale);
+
+	// Whether this context has an active item (read once per frame during context update).
 	bool HasActiveItem() const { return bHasActiveItem; }
 
-	// Cursor type desired by this context (this is updated during ImGui frame and cached here during context update, before it is reset).
+	// Whether ImGui will use the mouse inputs (read once per frame during context update).
+	bool WantsMouseCapture() const { return bWantsMouseCapture; }
+
+	// Cursor type desired by this context (updated once per frame during context update).
 	EMouseCursor::Type GetMouseCursor() const { return MouseCursor;  }
 
-	// Delegate called right before ending the frame to allows listeners draw their controls.
+	// Internal draw event used to draw module's examples and debug widgets. Unlike the delegates container, it is not
+	// passed when the module is reloaded, so all objects that are unloaded with the module should register here.
 	FSimpleMulticastDelegate& OnDraw() { return DrawEvent; }
 
 	// Call early debug events to allow listeners draw their debug widgets.
@@ -106,18 +94,20 @@ private:
 	void BroadcastWorldDebug();
 	void BroadcastMultiContextDebug();
 
-	FImGuiContextPtr Context;
+	ImGuiContext* Context;
 
 	FVector2D DisplaySize = FVector2D::ZeroVector;
+	float DPIScale = 1.f;
 
 	EMouseCursor::Type MouseCursor = EMouseCursor::None;
 	bool bHasActiveItem = false;
+	bool bWantsMouseCapture = false;
 
 	bool bIsFrameStarted = false;
 	bool bIsDrawEarlyDebugCalled = false;
 	bool bIsDrawDebugCalled = false;
 
-	const FImGuiInputState* InputState = nullptr;
+	FImGuiInputState InputState;
 
 	TArray<FImGuiDrawList> DrawLists;
 
@@ -127,7 +117,6 @@ private:
 	uint32 LastFrameNumber = 0;
 
 	FSimpleMulticastDelegate DrawEvent;
-	FSimpleMulticastDelegate* SharedDrawEvent = nullptr;
 
 	std::string IniFilename;
 };

Source/ImGui/Private/ImGuiDelegates.cpp

@@ -1,10 +1,10 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiDelegates.h"
 #include "ImGuiDelegatesContainer.h"
 
+#include <Engine/World.h>
+
 
 FSimpleMulticastDelegate& FImGuiDelegates::OnWorldEarlyDebug()
 {

Source/ImGui/Private/ImGuiDelegatesContainer.cpp

@@ -1,30 +1,79 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiDelegatesContainer.h"
 
+#include "ImGuiModule.h"
 #include "Utilities/WorldContextIndex.h"
 
 
-FImGuiDelegatesContainer FImGuiDelegatesContainer::DefaultInstance;
+#if !WITH_EDITOR
+//
+// Non-editor version without container redirection
+//
 
-FImGuiDelegatesContainer* FImGuiDelegatesContainer::InstancePtr = &FImGuiDelegatesContainer::DefaultInstance;
+FImGuiDelegatesContainer& FImGuiDelegatesContainer::Get()
+{
+	static FImGuiDelegatesContainer* Container = new FImGuiDelegatesContainer();
+	return *Container;
+}
 
-void FImGuiDelegatesContainer::MoveContainer(FImGuiDelegatesContainer& Dst)
+#endif // !WITH_EDITOR
+
+
+#if WITH_EDITOR
+//
+// Editor version supporting container redirection needed for hot-reloading
+//
+
+#include "Utilities/RedirectingHandle.h"
+
+// Redirecting handle which will always bind to a container from the currently loaded module.
+struct FImGuiDelegatesContainerHandle : Utilities::TRedirectingHandle<FImGuiDelegatesContainer>
+{
+	FImGuiDelegatesContainerHandle(FImGuiDelegatesContainer& InDefaultContainer)
+		: Utilities::TRedirectingHandle<FImGuiDelegatesContainer>(InDefaultContainer)
+	{
+		if (FImGuiModule* Module = FModuleManager::GetModulePtr<FImGuiModule>("ImGui"))
+		{
+			SetParent(Module->DelegatesContainerHandle);
+		}
+	}
+};
+
+FImGuiDelegatesContainer& FImGuiDelegatesContainer::Get()
+{
+	return GetHandle().Get();
+}
+
+FImGuiDelegatesContainerHandle& FImGuiDelegatesContainer::GetHandle()
+{
+	struct FContainerInstance
+	{
+		FContainerInstance() : Container(), Handle(Container) {}
+		FImGuiDelegatesContainer Container;
+		FImGuiDelegatesContainerHandle Handle;
+	};
+	static FContainerInstance* Instance = new FContainerInstance();
+	return Instance->Handle;
+}
+
+void FImGuiDelegatesContainer::MoveContainer(FImGuiDelegatesContainerHandle& OtherContainerHandle)
 {
 	// Only move data if pointer points to default instance, otherwise our data has already been moved and we only
 	// keep pointer to a more recent version.
-	if (InstancePtr == &DefaultInstance)
+	if (GetHandle().IsDefault())
 	{
-		Dst = MoveTemp(DefaultInstance);
-		DefaultInstance.Clear();
+		OtherContainerHandle.Get() = MoveTemp(GetHandle().Get());
+		GetHandle().Get().Clear();
 	}
 
 	// Update pointer to the most recent version.
-	InstancePtr = &Dst;
+	GetHandle().SetParent(&OtherContainerHandle);
 }
 
+#endif // WITH_EDITOR
+
+
 int32 FImGuiDelegatesContainer::GetContextIndex(UWorld* World)
 {
 	return Utilities::GetWorldContextIndex(*World);

Source/ImGui/Private/ImGuiDelegatesContainer.h

@@ -6,15 +6,24 @@
 #include <Delegates/Delegate.h>
 
 
+#if WITH_EDITOR
+struct FImGuiDelegatesContainerHandle;
+#endif
+
 struct FImGuiDelegatesContainer
 {
 public:
 
 	// Get the current instance (can change during hot-reloading).
-	static FImGuiDelegatesContainer& Get() { return *InstancePtr; }
+	static FImGuiDelegatesContainer& Get();
 
-	// If this is an active container move its data to a destination and redirect all future calls to that instance.
-	static void MoveContainer(FImGuiDelegatesContainer& Dst);
+#if WITH_EDITOR
+	// Get the handle to the container instance (can attach to other handles in hot-reloaded modules).
+	static FImGuiDelegatesContainerHandle& GetHandle();
+
+	// Redirect to the other container and if this one is still active move its data to the other one.
+	static void MoveContainer(FImGuiDelegatesContainerHandle& OtherContainerHandle);
+#endif
 
 	// Get delegate to ImGui world early debug event from known world instance.
 	FSimpleMulticastDelegate& OnWorldEarlyDebug(UWorld* World) { return OnWorldEarlyDebug(GetContextIndex(World)); }
@@ -44,10 +53,4 @@ private:
 	TMap<int32, FSimpleMulticastDelegate> WorldDebugDelegates;
 	FSimpleMulticastDelegate MultiContextEarlyDebugDelegate;
 	FSimpleMulticastDelegate MultiContextDebugDelegate;
-
-	// Default container instance.
-	static FImGuiDelegatesContainer DefaultInstance;
-
-	// Pointer to the container instance that can be overwritten during hot-reloading.
-	static FImGuiDelegatesContainer* InstancePtr;
 };

Source/ImGui/Private/ImGuiDemo.cpp

@@ -1,11 +1,11 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiDemo.h"
 
 #include "ImGuiModuleProperties.h"
 
+#include <CoreGlobals.h>
+
 
 // Demo copied (with minor modifications) from ImGui examples. See https://github.com/ocornut/imgui.
 void FImGuiDemo::DrawControls(int32 ContextIndex)
@@ -33,7 +33,7 @@ void FImGuiDemo::DrawControls(int32 ContextIndex)
 		// 2. Show another simple window, this time using an explicit Begin/End pair
 		if (ShowAnotherWindowMask & ContextBit)
 		{
-			ImGui::SetNextWindowSize(ImVec2(200, 100), ImGuiSetCond_FirstUseEver);
+			ImGui::SetNextWindowSize(ImVec2(200, 100), ImGuiCond_FirstUseEver);
 			ImGui::Begin("Another Window");
 			ImGui::Text("Hello");
 			ImGui::End();
@@ -76,7 +76,7 @@ void FImGuiDemo::DrawControls(int32 ContextIndex)
 			}
 
 			// Draw demo window.
-			ImGui::SetNextWindowPos(ImVec2(650, 20), ImGuiSetCond_FirstUseEver);
+			ImGui::SetNextWindowPos(ImVec2(650, 20), ImGuiCond_FirstUseEver);
 			ImGui::ShowDemoWindow();
 		}
 	}

Source/ImGui/Private/ImGuiDemo.h

@@ -2,6 +2,8 @@
 
 #pragma once
 
+#include <CoreMinimal.h>
+
 #include <imgui.h>
 
 class FImGuiModuleProperties;

Source/ImGui/Private/ImGuiDrawData.cpp

@@ -1,7 +1,5 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiDrawData.h"
 
 
@@ -31,7 +29,11 @@ void FImGuiDrawList::CopyVertexData(TArray<FSlateVertex>& OutVertexBuffer, const
 		SlateVertex.Position[1] = VertexPosition.Y;
 		SlateVertex.ClipRect = VertexClippingRect;
 #else
+#if ENGINE_COMPATIBILITY_LEGACY_VECTOR2F
 		SlateVertex.Position = Transform.TransformPoint(ImGuiInterops::ToVector2D(ImGuiVertex.pos));
+#else
+		SlateVertex.Position = (FVector2f)Transform.TransformPoint(ImGuiInterops::ToVector2D(ImGuiVertex.pos));
+#endif // ENGINE_COMPATIBILITY_LEGACY_VECTOR2F
 #endif // ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API
 
 		// Unpack ImU32 color.
@@ -58,8 +60,4 @@ void FImGuiDrawList::TransferDrawData(ImDrawList& Src)
 	Src.CmdBuffer.swap(ImGuiCommandBuffer);
 	Src.IdxBuffer.swap(ImGuiIndexBuffer);
 	Src.VtxBuffer.swap(ImGuiVertexBuffer);
-
-	// ImGui seems to clear draw lists in every frame, but since source list can contain pointers to buffers that
-	// we just swapped, it is better to clear explicitly here.
-	Src.Clear();
 }

Source/ImGui/Private/ImGuiDrawData.h

@@ -3,9 +3,9 @@
 #pragma once
 
 #include "ImGuiInteroperability.h"
+#include "VersionCompatibility.h"
 
-#include <Runtime/Launch/Resources/Version.h>
-#include <SlateCore.h>
+#include <Rendering/RenderingCommon.h>
 
 #include <imgui.h>
 

Source/ImGui/Private/ImGuiImplementation.cpp

@@ -1,41 +1,59 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
+#include "ImGuiImplementation.h"
 
-// We build ImGui source code as part of this module. This is for convenience (no need to manually build libraries for
-// different target platforms) but it also exposes the whole ImGui source for inspection, which can be pretty handy.
-// Source files are included from Third Party directory, so we can wrap them in required by Unreal Build System headers
-// without modifications in ImGui source code.
-//
+#include <CoreMinimal.h>
+
+// For convenience and easy access to the ImGui source code, we build it as part of this module.
 // We don't need to define IMGUI_API manually because it is already done for this module.
-
+// UE 5.1 stopped defining PLATFORM_XBOXONE, so be safe if not defined
+#if !defined(PLATFORM_XBOXONE)
+	#define PLATFORM_XBOXONE 0
+#endif
 #if PLATFORM_XBOXONE
 // Disable Win32 functions used in ImGui and not supported on XBox.
 #define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS
 #define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS
 #endif // PLATFORM_XBOXONE
 
-#if WITH_EDITOR
-// Global ImGui context pointer.
-ImGuiContext* GImGuiContextPtr = nullptr;
-// Handle to the global ImGui context pointer.
-ImGuiContext** GImGuiContextPtrHandle = &GImGuiContextPtr;
-// Get the global ImGui context pointer (GImGui) indirectly to allow redirections in obsolete modules.
-#define GImGui (*GImGuiContextPtrHandle)
-#endif // WITH_EDITOR
-
 #if PLATFORM_WINDOWS
-#include <AllowWindowsPlatformTypes.h>
+#include <Windows/AllowWindowsPlatformTypes.h>
 #endif // PLATFORM_WINDOWS
 
+#if WITH_EDITOR
+
+#include "ImGuiModule.h"
+#include "Utilities/RedirectingHandle.h"
+
+// Redirecting handle which will automatically bind to another one, if a different instance of the module is loaded.
+struct FImGuiContextHandle : public Utilities::TRedirectingHandle<ImGuiContext*>
+{
+	FImGuiContextHandle(ImGuiContext*& InDefaultContext)
+		: Utilities::TRedirectingHandle<ImGuiContext*>(InDefaultContext)
+	{
+		if (FImGuiModule* Module = FModuleManager::GetModulePtr<FImGuiModule>("ImGui"))
+		{
+			SetParent(Module->ImGuiContextHandle);
+		}
+	}
+};
+
+static ImGuiContext* ImGuiContextPtr = nullptr;
+static FImGuiContextHandle ImGuiContextPtrHandle(ImGuiContextPtr);
+
+// Get the global ImGui context pointer (GImGui) indirectly to allow redirections in obsolete modules.
+#define GImGui (ImGuiContextPtrHandle.Get())
+#endif // WITH_EDITOR
+
 #include "imgui.cpp"
 #include "imgui_demo.cpp"
 #include "imgui_draw.cpp"
 #include "imgui_widgets.cpp"
-#include "misc/stl/imgui_stl.cpp"
+
+#include "imgui_tables.cpp"
 
 #if PLATFORM_WINDOWS
-#include <HideWindowsPlatformTypes.h>
+#include <Windows/HideWindowsPlatformTypes.h>
 #endif // PLATFORM_WINDOWS
 
 #include "ImGuiInteroperability.h"
@@ -44,14 +62,14 @@ ImGuiContext** GImGuiContextPtrHandle = &GImGuiContextPtr;
 namespace ImGuiImplementation
 {
 #if WITH_EDITOR
-	ImGuiContext** GetImGuiContextHandle()
+	FImGuiContextHandle& GetContextHandle()
 	{
-		return GImGuiContextPtrHandle;
+		return ImGuiContextPtrHandle;
 	}
 
-	void SetImGuiContextHandle(ImGuiContext** Handle)
+	void SetParentContextHandle(FImGuiContextHandle& Parent)
 	{
-		GImGuiContextPtrHandle = Handle;
+		ImGuiContextPtrHandle.SetParent(&Parent);
 	}
 #endif // WITH_EDITOR
-}
+}

Source/ImGui/Private/ImGuiImplementation.h

@@ -2,17 +2,16 @@
 
 #pragma once
 
-#include <imgui.h>
-
+struct FImGuiContextHandle;
 
 // Gives access to selected ImGui implementation features.
 namespace ImGuiImplementation
 {
 #if WITH_EDITOR
 	// Get the handle to the ImGui Context pointer.
-	ImGuiContext** GetImGuiContextHandle();
+	FImGuiContextHandle& GetContextHandle();
 
 	// Set the ImGui Context pointer handle.
-	void SetImGuiContextHandle(ImGuiContext** Handle);
+	void SetParentContextHandle(FImGuiContextHandle& Parent);
 #endif // WITH_EDITOR
 }

Source/ImGui/Private/ImGuiInputHandler.cpp

@@ -1,63 +1,264 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiInputHandler.h"
 
 #include "ImGuiContextProxy.h"
+#include "ImGuiInputState.h"
+#include "ImGuiModuleDebug.h"
 #include "ImGuiModuleManager.h"
 #include "ImGuiModuleSettings.h"
+#include "VersionCompatibility.h"
 
 #include <Engine/Console.h>
+#include <Framework/Application/SlateApplication.h>
+#include <GameFramework/InputSettings.h>
+#include <InputCoreTypes.h>
 #include <Input/Events.h>
 
 #if WITH_EDITOR
-#include <Commands/InputBindingManager.h>
-#include <Commands/InputChord.h>
-#include <DebuggerCommands.h>
+#include <Framework/Commands/InputBindingManager.h>
+#include <Framework/Commands/InputChord.h>
+#include <Kismet2/DebuggerCommands.h>
 #endif // WITH_EDITOR
 
 
 DEFINE_LOG_CATEGORY(LogImGuiInputHandler);
 
-static FImGuiInputResponse IgnoreResponse{ false, false };
-
-FImGuiInputResponse UImGuiInputHandler::OnKeyDown(const FKeyEvent& KeyEvent)
+namespace
 {
-	// Ignore console events, so we don't block it from opening.
-	if (IsConsoleEvent(KeyEvent))
+	FReply ToReply(bool bConsume)
 	{
-		return IgnoreResponse;
+		return bConsume ? FReply::Handled() : FReply::Unhandled();
 	}
+}
+
+FReply UImGuiInputHandler::OnKeyChar(const struct FCharacterEvent& CharacterEvent)
+{
+	InputState->AddCharacter(CharacterEvent.GetCharacter());
+	return ToReply(!ModuleManager->GetProperties().IsKeyboardInputShared());
+}
+
+FReply UImGuiInputHandler::OnKeyDown(const FKeyEvent& KeyEvent)
+{
+	if (KeyEvent.GetKey().IsGamepadKey())
+	{
+		bool bConsume = false;
+		if (InputState->IsGamepadNavigationEnabled())
+		{
+			// TODO: Update gamepad navigation to use new ImGuiKey API
+			//InputState->SetGamepadNavigationKey(KeyEvent, true);
+			bConsume = !ModuleManager->GetProperties().IsGamepadInputShared();
+		}
+
+		return ToReply(bConsume);
+	}
+	else
+	{
+		// Ignore console events, so we don't block it from opening.
+		if (IsConsoleEvent(KeyEvent))
+		{
+			return ToReply(false);
+		}
 
 #if WITH_EDITOR
-	// If there is no active ImGui control that would get precedence and this key event is bound to a stop play session
-	// command, then ignore that event and let the command execute.
-	if (!HasImGuiActiveItem() && IsStopPlaySessionEvent(KeyEvent))
-	{
-		return IgnoreResponse;
-	}
+		// If there is no active ImGui control that would get precedence and this key event is bound to a stop play session
+		// command, then ignore that event and let the command execute.
+		if (!HasImGuiActiveItem() && IsStopPlaySessionEvent(KeyEvent))
+		{
+			return ToReply(false);
+		}
 #endif // WITH_EDITOR
 
-	const FImGuiInputResponse Response = GetDefaultKeyboardResponse();
+		const bool bConsume = !ModuleManager->GetProperties().IsKeyboardInputShared();
 
-	// With shared input we can leave command bindings for DebugExec to handle, otherwise we need to do it here.
-	if (Response.HasConsumeRequest() && IsToggleInputEvent(KeyEvent))
+		// With shared input we can leave command bindings for DebugExec to handle, otherwise we need to do it here.
+		if (bConsume && IsToggleInputEvent(KeyEvent))
+		{
+			ModuleManager->GetProperties().ToggleInput();
+		}
+
+		InputState->SetKeyDown(KeyEvent, true);
+		CopyModifierKeys(KeyEvent);
+
+		InputState->KeyDownEvents.Add(KeyEvent.GetKeyCode(), KeyEvent);
+
+		return ToReply(bConsume);
+	}
+}
+
+FReply UImGuiInputHandler::OnKeyUp(const FKeyEvent& KeyEvent)
+{
+	InputState->KeyUpEvents.Add(KeyEvent.GetKeyCode(), KeyEvent);
+	
+	if (KeyEvent.GetKey().IsGamepadKey())
 	{
-		ModuleManager->GetProperties().ToggleInput();
+		bool bConsume = false;
+		if (InputState->IsGamepadNavigationEnabled())
+		{
+			// TODO: Update gamepad navigation to use new ImGuiKey API
+			//InputState->SetGamepadNavigationKey(KeyEvent, false);
+			bConsume = !ModuleManager->GetProperties().IsGamepadInputShared();
+		}
+
+		return ToReply(bConsume);
+	}
+	else
+	{
+		InputState->SetKeyDown(KeyEvent, false);
+		CopyModifierKeys(KeyEvent);
+
+		return ToReply(!ModuleManager->GetProperties().IsKeyboardInputShared());
+	}
+}
+
+FReply UImGuiInputHandler::OnAnalogValueChanged(const FAnalogInputEvent& AnalogInputEvent)
+{
+	bool bConsume = false;
+
+	if (AnalogInputEvent.GetKey().IsGamepadKey() && InputState->IsGamepadNavigationEnabled())
+	{
+		// TODO: Update gamepad navigation to use new ImGuiKey API
+		//InputState->SetGamepadNavigationAxis(AnalogInputEvent, AnalogInputEvent.GetAnalogValue());
+		bConsume = !ModuleManager->GetProperties().IsGamepadInputShared();
 	}
 
-	return Response;
+	return ToReply(bConsume);
 }
 
-FImGuiInputResponse UImGuiInputHandler::GetDefaultKeyboardResponse() const
+FReply UImGuiInputHandler::OnMouseButtonDown(const FPointerEvent& MouseEvent)
 {
-	return FImGuiInputResponse{ true, !ModuleManager->GetProperties().IsKeyboardInputShared() };
+	if (MouseEvent.IsTouchEvent())
+	{
+		return ToReply(false);
+	}
+
+	InputState->SetMouseDown(MouseEvent, true);
+	InputState->MouseButtonDownEvents.Add(ImGuiInterops::GetMouseIndex(MouseEvent.GetEffectingButton()), MouseEvent);
+	if (ModuleManager)
+	{
+		FImGuiContextProxy* Proxy = ModuleManager->GetContextManager().GetContextProxy(0);
+		if (Proxy)
+		{
+			//GEngine->AddOnScreenDebugMessage(15, 10, Proxy->WantsMouseCapture() ? FColor::Green : FColor::Red, TEXT("Handler Down"));
+			return ToReply(Proxy->WantsMouseCapture());
+		}
+	}
+	return ToReply(true);
 }
 
-FImGuiInputResponse UImGuiInputHandler::GetDefaultGamepadResponse() const
+FReply UImGuiInputHandler::OnMouseButtonDoubleClick(const FPointerEvent& MouseEvent)
 {
-	return FImGuiInputResponse{ true, !ModuleManager->GetProperties().IsGamepadInputShared() };
+	InputState->SetMouseDown(MouseEvent, true);
+	InputState->MouseButtonDownEvents.Add(ImGuiInterops::GetMouseIndex(MouseEvent.GetEffectingButton()), MouseEvent);
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnMouseButtonUp(const FPointerEvent& MouseEvent)
+{
+	if (MouseEvent.IsTouchEvent())
+	{
+		return ToReply(false);
+	}
+
+	InputState->SetMouseDown(MouseEvent, false);
+	InputState->MouseButtonUpEvents.Add(ImGuiInterops::GetMouseIndex(MouseEvent.GetEffectingButton()), MouseEvent);
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnMouseWheel(const FPointerEvent& MouseEvent)
+{
+	InputState->AddMouseWheelDelta(MouseEvent.GetWheelDelta());
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnMouseMove(const FVector2D& MousePosition, const FPointerEvent& MouseEvent)
+{
+	if (MouseEvent.IsTouchEvent())
+	{
+		return ToReply(false);
+	}
+
+	return OnMouseMove(MousePosition);
+}
+
+FReply UImGuiInputHandler::OnMouseMove(const FVector2D& MousePosition)
+{
+	InputState->SetMousePosition(MousePosition);
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnTouchStarted(const FVector2D& CursorPosition, const FPointerEvent& TouchEvent)
+{
+	InputState->SetTouchDown(true);
+	InputState->SetTouchPosition(CursorPosition);
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnTouchMoved(const FVector2D& CursorPosition, const FPointerEvent& TouchEvent)
+{
+	InputState->SetTouchPosition(CursorPosition);
+	return ToReply(true);
+}
+
+FReply UImGuiInputHandler::OnTouchEnded(const FVector2D& CursorPosition, const FPointerEvent& TouchEvent)
+{
+	InputState->SetTouchDown(false);
+	return ToReply(true);
+}
+
+void UImGuiInputHandler::OnKeyboardInputEnabled()
+{
+	bKeyboardInputEnabled = true;
+}
+
+void UImGuiInputHandler::OnKeyboardInputDisabled()
+{
+	if (bKeyboardInputEnabled)
+	{
+		bKeyboardInputEnabled = false;
+		InputState->ResetKeyboard();
+	}
+}
+
+void UImGuiInputHandler::OnGamepadInputEnabled()
+{
+	bGamepadInputEnabled = true;
+}
+
+void UImGuiInputHandler::OnGamepadInputDisabled()
+{
+	if (bGamepadInputEnabled)
+	{
+		bGamepadInputEnabled = false;
+		// TODO: Update gamepad navigation to use new ImGuiKey API
+		//InputState->ResetGamepadNavigation();
+	}
+}
+
+void UImGuiInputHandler::OnMouseInputEnabled()
+{
+	if (!bMouseInputEnabled)
+	{
+		bMouseInputEnabled = true;
+		UpdateInputStatePointer();
+	}
+}
+
+void UImGuiInputHandler::OnMouseInputDisabled()
+{
+	if (bMouseInputEnabled)
+	{
+		bMouseInputEnabled = false;
+		InputState->ResetMouse();
+		UpdateInputStatePointer();
+	}
+}
+
+void UImGuiInputHandler::CopyModifierKeys(const FInputEvent& InputEvent)
+{
+	InputState->SetControlDown(InputEvent.IsControlDown());
+	InputState->SetShiftDown(InputEvent.IsShiftDown());
+	InputState->SetAltDown(InputEvent.IsAltDown());
 }
 
 bool UImGuiInputHandler::IsConsoleEvent(const FKeyEvent& KeyEvent) const
@@ -113,12 +314,47 @@ bool UImGuiInputHandler::HasImGuiActiveItem() const
 	return ContextProxy && ContextProxy->HasActiveItem();
 }
 
+void UImGuiInputHandler::UpdateInputStatePointer()
+{
+	InputState->SetMousePointer(bMouseInputEnabled && ModuleManager->GetSettings().UseSoftwareCursor());
+}
+
+void UImGuiInputHandler::OnSoftwareCursorChanged(bool)
+{
+	UpdateInputStatePointer();
+}
+
+void UImGuiInputHandler::OnPostImGuiUpdate()
+{
+	InputState->ClearUpdateState();
+
+	// TODO Replace with delegates after adding property change events.
+	InputState->SetKeyboardNavigationEnabled(ModuleManager->GetProperties().IsKeyboardNavigationEnabled());
+	InputState->SetGamepadNavigationEnabled(ModuleManager->GetProperties().IsGamepadNavigationEnabled());
+
+	const auto& PlatformApplication = FSlateApplication::Get().GetPlatformApplication();
+	InputState->SetGamepad(PlatformApplication.IsValid() && PlatformApplication->IsGamepadAttached());
+}
+
 void UImGuiInputHandler::Initialize(FImGuiModuleManager* InModuleManager, UGameViewportClient* InGameViewport, int32 InContextIndex)
 {
 	ModuleManager = InModuleManager;
 	GameViewport = InGameViewport;
 	ContextIndex = InContextIndex;
 
+	auto* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
+	checkf(ContextProxy, TEXT("Missing context during initialization of input handler: ContextIndex = %d"), ContextIndex);
+	InputState = &ContextProxy->GetInputState();
+
+	// Register to get post-update notifications, so we can clean frame updates.
+	ModuleManager->OnPostImGuiUpdate().AddUObject(this, &UImGuiInputHandler::OnPostImGuiUpdate);
+
+	auto& Settings = ModuleManager->GetSettings();
+	if (!Settings.OnUseSoftwareCursorChanged.IsBoundToObject(this))
+	{
+		Settings.OnUseSoftwareCursorChanged.AddUObject(this, &UImGuiInputHandler::OnSoftwareCursorChanged);
+	}
+
 #if WITH_EDITOR
 	StopPlaySessionCommandInfo = FInputBindingManager::Get().FindCommandInContext("PlayWorld", "StopPlaySession");
 	if (!StopPlaySessionCommandInfo.IsValid())
@@ -128,3 +364,16 @@ void UImGuiInputHandler::Initialize(FImGuiModuleManager* InModuleManager, UGameV
 	}
 #endif // WITH_EDITOR
 }
+
+void UImGuiInputHandler::BeginDestroy()
+{
+	Super::BeginDestroy();
+
+	// To catch leftovers from modules shutdown during PIE session.
+	extern FImGuiModuleManager* ImGuiModuleManager;
+	if (ModuleManager && ModuleManager == ImGuiModuleManager)
+	{
+		ModuleManager->GetSettings().OnUseSoftwareCursorChanged.RemoveAll(this);
+	}
+}
+

Source/ImGui/Private/ImGuiInputHandlerFactory.cpp

@@ -1,13 +1,15 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiInputHandlerFactory.h"
-
 #include "ImGuiInputHandler.h"
 
+#include "ImGuiModuleDebug.h"
 
-UImGuiInputHandler* FImGuiInputHandlerFactory::NewHandler(const FStringClassReference& HandlerClassReference, FImGuiModuleManager* ModuleManager, UGameViewportClient* GameViewport, int32 ContextIndex)
+#include <Engine/GameViewportClient.h>
+#include <InputCoreTypes.h>
+
+
+UImGuiInputHandler* FImGuiInputHandlerFactory::NewHandler(const FSoftClassPath& HandlerClassReference, FImGuiModuleManager* ModuleManager, UGameViewportClient* GameViewport, int32 ContextIndex)
 {
 	UClass* HandlerClass = nullptr;
 	if (HandlerClassReference.IsValid())

Source/ImGui/Private/ImGuiInputHandlerFactory.h

@@ -2,6 +2,9 @@
 
 #pragma once
 
+#include "ImGuiModuleSettings.h"
+
+
 class FImGuiModuleManager;
 class UGameViewportClient;
 class UImGuiInputHandler;
@@ -10,7 +13,7 @@ class FImGuiInputHandlerFactory
 {
 public:
 
-	static UImGuiInputHandler* NewHandler(const FStringClassReference& HandlerClassReference, FImGuiModuleManager* ModuleManager, UGameViewportClient* GameViewport, int32 ContextIndex);
+	static UImGuiInputHandler* NewHandler(const FSoftClassPath& HandlerClassReference, FImGuiModuleManager* ModuleManager, UGameViewportClient* GameViewport, int32 ContextIndex);
 
 	static void ReleaseHandler(UImGuiInputHandler* Handler);
 };

Source/ImGui/Private/ImGuiInputState.cpp

@@ -1,7 +1,5 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiInputState.h"
 
 #include <algorithm>
@@ -9,56 +7,17 @@
 #include <type_traits>
 
 
-// If TCHAR is wider than ImWchar, enable or disable validation of input character before conversions.
-#define VALIDATE_INPUT_CHARACTERS 1
-
-#if VALIDATE_INPUT_CHARACTERS
-DEFINE_LOG_CATEGORY_STATIC(LogImGuiInput, Warning, All);
-#endif
-
-namespace
-{
-	template<typename T, std::enable_if_t<(sizeof(T) <= sizeof(ImWchar)), T>* = nullptr>
-	ImWchar CastInputChar(T Char)
-	{
-		return static_cast<ImWchar>(Char);
-	}
-
-	template<typename T, std::enable_if_t<!(sizeof(T) <= sizeof(ImWchar)), T>* = nullptr>
-	ImWchar CastInputChar(T Char)
-	{
-#if VALIDATE_INPUT_CHARACTERS
-		// We only need a runtime validation if TCHAR is wider than ImWchar.
-		// Signed and unsigned integral types with the same size as ImWchar should be safely converted. As long as the
-		// char value is in that range we can safely use it, otherwise we should log an error to notify about possible
-		// truncations.
-		static constexpr auto MinLimit = (std::numeric_limits<std::make_signed_t<ImWchar>>::min)();
-		static constexpr auto MaxLimit = (std::numeric_limits<std::make_unsigned_t<ImWchar>>::max)();
-		UE_CLOG(!(Char >= MinLimit && Char <= MaxLimit), LogImGuiInput, Error,
-			TEXT("TCHAR value '%c' (%#x) is out of range %d (%#x) to %u (%#x) that can be safely converted to ImWchar. ")
-			TEXT("If you wish to disable this validation, please set VALIDATE_INPUT_CHARACTERS in ImGuiInputState.cpp to 0."),
-			Char, Char, MinLimit, MinLimit, MaxLimit, MaxLimit);
-#endif
-
-		return static_cast<ImWchar>(Char);
-	}
-}
-
 FImGuiInputState::FImGuiInputState()
 {
-	ResetState();
+	Reset();
 }
 
 void FImGuiInputState::AddCharacter(TCHAR Char)
 {
-	if (InputCharactersNum < Utilities::GetArraySize(InputCharacters))
-	{
-		InputCharacters[InputCharactersNum++] = CastInputChar(Char);
-		InputCharacters[InputCharactersNum] = 0;
-	}
+	InputCharacters.Add(Char);
 }
 
-void FImGuiInputState::SetKeyDown(uint32 KeyIndex, bool bIsDown)
+void FImGuiInputState::SetKeyDown(ImGuiKey KeyIndex, bool bIsDown)
 {
 	if (KeyIndex < Utilities::GetArraySize(KeysDown))
 	{
@@ -82,49 +41,26 @@ void FImGuiInputState::SetMouseDown(uint32 MouseIndex, bool bIsDown)
 	}
 }
 
-void FImGuiInputState::Reset(bool bKeyboard, bool bMouse, bool bNavigation)
-{
-	if (bKeyboard)
-	{
-		ClearCharacters();
-		ClearKeys();
-	}
-
-	if (bMouse)
-	{
-		ClearMouseButtons();
-		ClearMouseAnalogue();
-	}
-
-	if (bKeyboard && bMouse)
-	{
-		ClearModifierKeys();
-	}
-
-	if (bNavigation)
-	{
-		ClearNavigationInputs();
-	}
-}
-
 void FImGuiInputState::ClearUpdateState()
 {
-	if (InputCharactersNum > 0)
-	{
-		ClearCharacters();
-	}
+	ClearCharacters();
 
+	KeyDownEvents.Reset();
+	KeyUpEvents.Reset();
+	MouseButtonDownEvents.Reset();
+	MouseButtonUpEvents.Reset();
+	
 	KeysUpdateRange.SetEmpty();
 	MouseButtonsUpdateRange.SetEmpty();
 
 	MouseWheelDelta = 0.f;
+
+	bTouchProcessed = bTouchDown;
 }
 
 void FImGuiInputState::ClearCharacters()
 {
-	using std::fill;
-	fill(InputCharacters, &InputCharacters[Utilities::GetArraySize(InputCharacters)], 0);
-	InputCharactersNum = 0;
+	InputCharacters.Empty();
 }
 
 void FImGuiInputState::ClearKeys()
@@ -132,7 +68,7 @@ void FImGuiInputState::ClearKeys()
 	using std::fill;
 	fill(KeysDown, &KeysDown[Utilities::GetArraySize(KeysDown)], false);
 
-	// Expand update range because keys array has been updated.
+	// Mark the whole array as dirty because potentially each entry could be affected.
 	KeysUpdateRange.SetFull();
 }
 
@@ -141,7 +77,7 @@ void FImGuiInputState::ClearMouseButtons()
 	using std::fill;
 	fill(MouseButtonsDown, &MouseButtonsDown[Utilities::GetArraySize(MouseButtonsDown)], false);
 
-	// Expand update range because mouse buttons array has been updated.
+	// Mark the whole array as dirty because potentially each entry could be affected.
 	MouseButtonsUpdateRange.SetFull();
 }
 
@@ -158,9 +94,3 @@ void FImGuiInputState::ClearModifierKeys()
 	bIsAltDown = false;
 }
 
-void FImGuiInputState::ClearNavigationInputs()
-{
-	using std::fill;
-	fill(NavigationInputs, &NavigationInputs[Utilities::GetArraySize(NavigationInputs)], 0.f);
-}
-

Source/ImGui/Private/ImGuiInputState.h

@@ -5,6 +5,8 @@
 #include "ImGuiInteroperability.h"
 #include "Utilities/Arrays.h"
 
+#include <Containers/Array.h>
+
 
 // Collects and stores input state and updates for ImGui IO.
 class FImGuiInputState
@@ -12,7 +14,7 @@ class FImGuiInputState
 public:
 
 	// Characters buffer.
-	using FCharactersBuffer = ImGuiInterops::ImGuiTypes::FInputCharactersBuffer;
+	using FCharactersBuffer = TArray<TCHAR, TInlineAllocator<8>>;
 
 	// Array for mouse button states.
 	using FMouseButtonsArray = ImGuiInterops::ImGuiTypes::FMouseButtonsArray;
@@ -20,9 +22,6 @@ public:
 	// Array for key states.
 	using FKeysArray = ImGuiInterops::ImGuiTypes::FKeysArray;
 
-	// Array for navigation input states.
-	using FNavInputArray = ImGuiInterops::ImGuiTypes::FNavInputArray;
-
 	// Pair of indices defining range in mouse buttons array.
 	using FMouseButtonsIndexRange = Utilities::TArrayIndexRange<FMouseButtonsArray, uint32>;
 
@@ -35,9 +34,6 @@ public:
 	// Get reference to input characters buffer.
 	const FCharactersBuffer& GetCharacters() const { return InputCharacters; }
 
-	// Get number of characters in input characters buffer.
-	int32 GetCharactersNum()  const { return InputCharactersNum; }
-
 	// Add a character to the characters buffer. We can store and send to ImGui up to 16 characters per frame. Any
 	// character beyond that limit will be discarded.
 	// @param Char - Character to add
@@ -82,11 +78,11 @@ public:
 	// @param DeltaValue - Mouse wheel delta to add
 	void AddMouseWheelDelta(float DeltaValue) { MouseWheelDelta += DeltaValue; }
 
-	// Get the current mouse position.
+	// Get the mouse position.
 	const FVector2D& GetMousePosition() const { return MousePosition; }
 
-	// Set mouse position.
-	// @param Position - New mouse position
+	// Set the mouse position.
+	// @param Position - Mouse position
 	void SetMousePosition(const FVector2D& Position) { MousePosition = Position; }
 
 	// Check whether input has active mouse pointer.
@@ -96,6 +92,24 @@ public:
 	// @param bHasPointer - True, if input has active mouse pointer
 	void SetMousePointer(bool bInHasMousePointer) { bHasMousePointer = bInHasMousePointer; }
 
+	// Check whether touch input is in progress. True, after touch is started until one frame after it has ended.
+	// One frame delay is used to process mouse release in ImGui since touch-down is simulated with mouse-down.
+	bool IsTouchActive() const { return bTouchDown || bTouchProcessed; }
+
+	// Check whether touch input is down.
+	bool IsTouchDown() const { return bTouchDown; }
+
+	// Set whether touch input is down.
+	// @param bIsDown - True, if touch is down (or started) and false, if touch is up (or ended)
+	void SetTouchDown(bool bIsDown) { bTouchDown = bIsDown; }
+
+	// Get the touch position.
+	const FVector2D& GetTouchPosition() const { return TouchPosition; }
+
+	// Set the touch position.
+	// @param Position - Touch position
+	void SetTouchPosition(const FVector2D& Position) { TouchPosition = Position; }
+
 	// Get Control down state.
 	bool IsControlDown() const { return bIsControlDown; }
 
@@ -117,9 +131,8 @@ public:
 	// @param bIsDown - True, if Alt is down
 	void SetAltDown(bool bIsDown) { bIsAltDown = bIsDown; }
 
-	// Get reference to the array with navigation input states.
-	const FNavInputArray& GetNavigationInputs() const { return NavigationInputs; }
-
+	// TODO: Update gamepad navigation to use new ImGuiKey API
+	/*
 	// Change state of the navigation input associated with this gamepad key.
 	// @param KeyEvent - Key event with gamepad key input
 	// @param bIsDown - True, if key is down
@@ -129,6 +142,7 @@ public:
 	// @param AnalogInputEvent - Analogue input event with gamepad axis input
 	// @param Value - Analogue value that should be set for this axis
 	void SetGamepadNavigationAxis(const FAnalogInputEvent& AnalogInputEvent, float Value) { ImGuiInterops::SetGamepadNavigationAxis(NavigationInputs, AnalogInputEvent.GetKey(), Value); }
+	*/
 
 	// Check whether keyboard navigation is enabled.
 	bool IsKeyboardNavigationEnabled() const { return bKeyboardNavigationEnabled; }
@@ -151,51 +165,74 @@ public:
 	// @param bInHasGamepad - True, if gamepad is attached
 	void SetGamepad(bool bInHasGamepad) { bHasGamepad = bInHasGamepad; }
 
-	// Reset the whole state and mark as dirty.
-	void ResetState() { Reset(true, true, true); }
+	// Reset the whole input state and mark it as dirty.
+	void Reset()
+	{
+		ResetKeyboard();
+		ResetMouse();
+		// TODO: Update gamepad navigation to use new ImGuiKey API
+		//ResetGamepadNavigation();
+	}
 
-	// Reset keyboard state and mark as dirty.
-	void ResetKeyboardState() { Reset(true, false, false); }
+	// Reset the keyboard input state and mark it as dirty.
+	void ResetKeyboard()
+	{
+		ClearCharacters();
+		ClearKeys();
+		ClearModifierKeys();
+	}
 
-	// Reset mouse state and mark as dirty.
-	void ResetMouseState() { Reset(false, true, false); }
+	// Reset the mouse input state and mark it as dirty.
+	void ResetMouse()
+	{
+		ClearMouseButtons();
+		ClearMouseAnalogue();
+	}
 
-	// Reset navigation state.
-	void ResetNavigationState() { Reset(false, false, true); }
+	// TODO: Update gamepad navigation to use new ImGuiKey API
+	/*
+	// Reset the gamepad navigation state.
+	void ResetGamepadNavigation()
+	{
+		ClearNavigationInputs();
+	}
+	*/
 
 	// Clear part of the state that is meant to be updated in every frame like: accumulators, buffers, navigation data
 	// and information about dirty parts of keys or mouse buttons arrays.
 	void ClearUpdateState();
 
+	TMap<uint32, FKeyEvent> KeyDownEvents;
+	TMap<uint32, FKeyEvent> KeyUpEvents;
+	TMap<uint32, FPointerEvent> MouseButtonDownEvents;
+	TMap<uint32, FPointerEvent> MouseButtonUpEvents;
+
 private:
 
-	void SetKeyDown(uint32 KeyIndex, bool bIsDown);
+	void SetKeyDown(ImGuiKey KeyIndex, bool bIsDown);
 	void SetMouseDown(uint32 MouseIndex, bool IsDown);
 
-	void Reset(bool bKeyboard, bool bMouse, bool bNavigation);
-
 	void ClearCharacters();
 	void ClearKeys();
 	void ClearMouseButtons();
 	void ClearMouseAnalogue();
 	void ClearModifierKeys();
-	void ClearNavigationInputs();
 
 	FVector2D MousePosition = FVector2D::ZeroVector;
+	FVector2D TouchPosition = FVector2D::ZeroVector;
 	float MouseWheelDelta = 0.f;
 
 	FMouseButtonsArray MouseButtonsDown;
 	FMouseButtonsIndexRange MouseButtonsUpdateRange;
 
 	FCharactersBuffer InputCharacters;
-	uint32 InputCharactersNum = 0;
 
 	FKeysArray KeysDown;
 	FKeysIndexRange KeysUpdateRange;
-
-	FNavInputArray NavigationInputs;
-
+	
 	bool bHasMousePointer = false;
+	bool bTouchDown = false;
+	bool bTouchProcessed = false;
 
 	bool bIsControlDown = false;
 	bool bIsShiftDown = false;

Source/ImGui/Private/ImGuiInteroperability.cpp

@@ -1,14 +1,50 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiInteroperability.h"
+
 #include "ImGuiInputState.h"
+#include "ImGuiModule.h"
 #include "Utilities/Arrays.h"
 
 
+// If TCHAR is wider than ImWchar, enable or disable validation of input character before conversions.
+#define VALIDATE_INPUT_CHARACTERS 1
+
+#if VALIDATE_INPUT_CHARACTERS
+DEFINE_LOG_CATEGORY_STATIC(LogImGuiInput, Warning, All);
+#endif
+
 namespace
 {
+	//====================================================================================================
+	// Character conversion
+	//====================================================================================================
+
+	template<typename T, std::enable_if_t<(sizeof(T) <= sizeof(ImWchar)), T>* = nullptr>
+	ImWchar CastInputChar(T Char)
+	{
+		return static_cast<ImWchar>(Char);
+	}
+
+	template<typename T, std::enable_if_t<!(sizeof(T) <= sizeof(ImWchar)), T>* = nullptr>
+	ImWchar CastInputChar(T Char)
+	{
+#if VALIDATE_INPUT_CHARACTERS
+		// We only need a runtime validation if TCHAR is wider than ImWchar.
+		// Signed and unsigned integral types with the same size as ImWchar should be safely converted. As long as the
+		// char value is in that range we can safely use it, otherwise we should log an error to notify about possible
+		// truncations.
+		static constexpr auto MinLimit = (std::numeric_limits<std::make_signed_t<ImWchar>>::min)();
+		static constexpr auto MaxLimit = (std::numeric_limits<std::make_unsigned_t<ImWchar>>::max)();
+		UE_CLOG(!(Char >= MinLimit && Char <= MaxLimit), LogImGuiInput, Error,
+			TEXT("TCHAR value '%c' (%#x) is out of range %d (%#x) to %u (%#x) that can be safely converted to ImWchar. ")
+			TEXT("If you wish to disable this validation, please set VALIDATE_INPUT_CHARACTERS in ImGuiInputState.cpp to 0."),
+			Char, Char, MinLimit, MinLimit, MaxLimit, MaxLimit);
+#endif
+
+		return static_cast<ImWchar>(Char);
+	}
+
 	//====================================================================================================
 	// Copying Utilities
 	//====================================================================================================
@@ -50,61 +86,139 @@ namespace ImGuiInterops
 	// Input Mapping
 	//====================================================================================================
 
+	static TMap<FKey, ImGuiKey> UnrealToImGuiKeyMap;
+
 	void SetUnrealKeyMap(ImGuiIO& IO)
 	{
-		struct FUnrealToImGuiMapping
-		{
-			FUnrealToImGuiMapping()
-			{
-				KeyMap[ImGuiKey_Tab] = GetKeyIndex(EKeys::Tab);
-				KeyMap[ImGuiKey_LeftArrow] = GetKeyIndex(EKeys::Left);
-				KeyMap[ImGuiKey_RightArrow] = GetKeyIndex(EKeys::Right);
-				KeyMap[ImGuiKey_UpArrow] = GetKeyIndex(EKeys::Up);
-				KeyMap[ImGuiKey_DownArrow] = GetKeyIndex(EKeys::Down);
-				KeyMap[ImGuiKey_PageUp] = GetKeyIndex(EKeys::PageUp);
-				KeyMap[ImGuiKey_PageDown] = GetKeyIndex(EKeys::PageDown);
-				KeyMap[ImGuiKey_Home] = GetKeyIndex(EKeys::Home);
-				KeyMap[ImGuiKey_End] = GetKeyIndex(EKeys::End);
-				KeyMap[ImGuiKey_Insert] = GetKeyIndex(EKeys::Insert);
-				KeyMap[ImGuiKey_Delete] = GetKeyIndex(EKeys::Delete);
-				KeyMap[ImGuiKey_Backspace] = GetKeyIndex(EKeys::BackSpace);
-				KeyMap[ImGuiKey_Space] = GetKeyIndex(EKeys::SpaceBar);
-				KeyMap[ImGuiKey_Enter] = GetKeyIndex(EKeys::Enter);
-				KeyMap[ImGuiKey_Escape] = GetKeyIndex(EKeys::Escape);
-				KeyMap[ImGuiKey_A] = GetKeyIndex(EKeys::A);
-				KeyMap[ImGuiKey_C] = GetKeyIndex(EKeys::C);
-				KeyMap[ImGuiKey_V] = GetKeyIndex(EKeys::V);
-				KeyMap[ImGuiKey_X] = GetKeyIndex(EKeys::X);
-				KeyMap[ImGuiKey_Y] = GetKeyIndex(EKeys::Y);
-				KeyMap[ImGuiKey_Z] = GetKeyIndex(EKeys::Z);
-			}
+		UnrealToImGuiKeyMap.Add(EKeys::Tab, ImGuiKey_Tab);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::Left,  ImGuiKey_LeftArrow);
+		UnrealToImGuiKeyMap.Add(EKeys::Right, ImGuiKey_RightArrow);
+		UnrealToImGuiKeyMap.Add(EKeys::Up,    ImGuiKey_UpArrow);
+		UnrealToImGuiKeyMap.Add(EKeys::Down,  ImGuiKey_DownArrow);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::PageUp,   ImGuiKey_PageUp);
+		UnrealToImGuiKeyMap.Add(EKeys::PageDown, ImGuiKey_PageDown);
+		UnrealToImGuiKeyMap.Add(EKeys::Home,     ImGuiKey_Home);
+		UnrealToImGuiKeyMap.Add(EKeys::End,      ImGuiKey_End);
+		UnrealToImGuiKeyMap.Add(EKeys::Insert,   ImGuiKey_Insert);
+		UnrealToImGuiKeyMap.Add(EKeys::Delete,   ImGuiKey_Delete);
 
-			ImGuiTypes::FKeyMap KeyMap;
-		};
+		UnrealToImGuiKeyMap.Add(EKeys::NumLock,    ImGuiKey_NumLock);
+		UnrealToImGuiKeyMap.Add(EKeys::ScrollLock, ImGuiKey_ScrollLock);
+		UnrealToImGuiKeyMap.Add(EKeys::Pause,      ImGuiKey_Pause);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::BackSpace, ImGuiKey_Backspace);
+		UnrealToImGuiKeyMap.Add(EKeys::SpaceBar,  ImGuiKey_Space);
+		UnrealToImGuiKeyMap.Add(EKeys::Enter,     ImGuiKey_Enter);
+		UnrealToImGuiKeyMap.Add(EKeys::Escape,     ImGuiKey_Escape);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::A, ImGuiKey_A);
+		UnrealToImGuiKeyMap.Add(EKeys::B, ImGuiKey_B);
+		UnrealToImGuiKeyMap.Add(EKeys::C, ImGuiKey_C);
+		UnrealToImGuiKeyMap.Add(EKeys::D, ImGuiKey_D);
+		UnrealToImGuiKeyMap.Add(EKeys::E, ImGuiKey_E);
+		UnrealToImGuiKeyMap.Add(EKeys::F, ImGuiKey_F);
+		UnrealToImGuiKeyMap.Add(EKeys::G, ImGuiKey_G);
+		UnrealToImGuiKeyMap.Add(EKeys::H, ImGuiKey_H);
+		UnrealToImGuiKeyMap.Add(EKeys::I, ImGuiKey_I);
+		UnrealToImGuiKeyMap.Add(EKeys::J, ImGuiKey_J);
+		UnrealToImGuiKeyMap.Add(EKeys::K, ImGuiKey_K);
+		UnrealToImGuiKeyMap.Add(EKeys::L, ImGuiKey_L);
+		UnrealToImGuiKeyMap.Add(EKeys::M, ImGuiKey_M);
+		UnrealToImGuiKeyMap.Add(EKeys::N, ImGuiKey_N);
+		UnrealToImGuiKeyMap.Add(EKeys::O, ImGuiKey_O);
+		UnrealToImGuiKeyMap.Add(EKeys::P, ImGuiKey_P);
+		UnrealToImGuiKeyMap.Add(EKeys::Q, ImGuiKey_Q);
+		UnrealToImGuiKeyMap.Add(EKeys::R, ImGuiKey_R);
+		UnrealToImGuiKeyMap.Add(EKeys::S, ImGuiKey_S);
+		UnrealToImGuiKeyMap.Add(EKeys::T, ImGuiKey_T);
+		UnrealToImGuiKeyMap.Add(EKeys::U, ImGuiKey_U);
+		UnrealToImGuiKeyMap.Add(EKeys::V, ImGuiKey_V);
+		UnrealToImGuiKeyMap.Add(EKeys::W, ImGuiKey_W);
+		UnrealToImGuiKeyMap.Add(EKeys::X, ImGuiKey_X);
+		UnrealToImGuiKeyMap.Add(EKeys::Y, ImGuiKey_Y);
+		UnrealToImGuiKeyMap.Add(EKeys::Z, ImGuiKey_Z);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::F1,  ImGuiKey_F1);
+		UnrealToImGuiKeyMap.Add(EKeys::F2,  ImGuiKey_F2);
+		UnrealToImGuiKeyMap.Add(EKeys::F3,  ImGuiKey_F3);
+		UnrealToImGuiKeyMap.Add(EKeys::F4,  ImGuiKey_F4);
+		UnrealToImGuiKeyMap.Add(EKeys::F5,  ImGuiKey_F5);
+		UnrealToImGuiKeyMap.Add(EKeys::F6,  ImGuiKey_F6);
+		UnrealToImGuiKeyMap.Add(EKeys::F7,  ImGuiKey_F7);
+		UnrealToImGuiKeyMap.Add(EKeys::F8,  ImGuiKey_F8);
+		UnrealToImGuiKeyMap.Add(EKeys::F9,  ImGuiKey_F9);
+		UnrealToImGuiKeyMap.Add(EKeys::F10, ImGuiKey_F10);
+		UnrealToImGuiKeyMap.Add(EKeys::F11, ImGuiKey_F11);
+		UnrealToImGuiKeyMap.Add(EKeys::F12, ImGuiKey_F12);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::One,   ImGuiKey_0);
+		UnrealToImGuiKeyMap.Add(EKeys::Two,   ImGuiKey_1);
+		UnrealToImGuiKeyMap.Add(EKeys::Three, ImGuiKey_2);
+		UnrealToImGuiKeyMap.Add(EKeys::Four,  ImGuiKey_3);
+		UnrealToImGuiKeyMap.Add(EKeys::Five,  ImGuiKey_4);
+		UnrealToImGuiKeyMap.Add(EKeys::Six,   ImGuiKey_5);
+		UnrealToImGuiKeyMap.Add(EKeys::Seven, ImGuiKey_6);
+		UnrealToImGuiKeyMap.Add(EKeys::Eight, ImGuiKey_7);
+		UnrealToImGuiKeyMap.Add(EKeys::Nine,  ImGuiKey_8);
+		
+		UnrealToImGuiKeyMap.Add(EKeys::Equals,       ImGuiKey_Equal);
+		UnrealToImGuiKeyMap.Add(EKeys::Comma,        ImGuiKey_Comma);
+		UnrealToImGuiKeyMap.Add(EKeys::Period,       ImGuiKey_Period);
+		UnrealToImGuiKeyMap.Add(EKeys::Slash,        ImGuiKey_Slash);
+		UnrealToImGuiKeyMap.Add(EKeys::LeftBracket,  ImGuiKey_LeftBracket);
+		UnrealToImGuiKeyMap.Add(EKeys::RightBracket, ImGuiKey_RightBracket);
+		UnrealToImGuiKeyMap.Add(EKeys::Apostrophe,   ImGuiKey_Apostrophe);
+		UnrealToImGuiKeyMap.Add(EKeys::Semicolon,    ImGuiKey_Semicolon);
 
-		static const FUnrealToImGuiMapping Mapping;
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadZero,  ImGuiKey_Keypad0);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadOne,   ImGuiKey_Keypad1);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadTwo,   ImGuiKey_Keypad2);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadThree, ImGuiKey_Keypad3);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadFour,  ImGuiKey_Keypad4);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadFive,  ImGuiKey_Keypad5);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadSix,   ImGuiKey_Keypad6);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadSeven, ImGuiKey_Keypad7);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadEight, ImGuiKey_Keypad8);
+		UnrealToImGuiKeyMap.Add(EKeys::NumPadNine,  ImGuiKey_Keypad9);
 
-		Copy(Mapping.KeyMap, IO.KeyMap);
+		UnrealToImGuiKeyMap.Add(EKeys::Multiply, ImGuiKey_KeypadMultiply);
+		UnrealToImGuiKeyMap.Add(EKeys::Add,      ImGuiKey_KeypadAdd);
+		UnrealToImGuiKeyMap.Add(EKeys::Subtract, ImGuiKey_KeypadSubtract);
+		UnrealToImGuiKeyMap.Add(EKeys::Decimal,  ImGuiKey_KeypadDecimal);
+		UnrealToImGuiKeyMap.Add(EKeys::Divide,   ImGuiKey_KeypadDivide);
 	}
 
-	uint32 GetKeyIndex(const FKey& Key)
+	// Simple transform mapping key codes to 0-511 range used in ImGui.
+	// From what I can tell, on most supported platforms key codes should comfortably fit in that range anyway
+	// but the SDL key-codes used on Linux can go way out of this range (because of the extra flag). However,
+	// after this transform they should fit in the range without conflicts.
+	// NOTE: Should any of the platforms have other conflicts or any trouble with inputs, this is the likely
+	// candidate for change.
+	static ImGuiKey MapKeyCode(uint32 KeyCode)
+	{
+		return static_cast<ImGuiKey>((KeyCode < 512) ? KeyCode : 256 + (KeyCode % 256));
+	}
+
+	ImGuiKey GetKeyIndex(const FKey& Key)
 	{
 		const uint32* pKeyCode = nullptr;
 		const uint32* pCharCode = nullptr;
 
 		FInputKeyManager::Get().GetCodesFromKey(Key, pKeyCode, pCharCode);
 
-		if (pKeyCode)
-		{
-			return *pKeyCode;
-		}
+		const uint32 KeyCode =
+			pKeyCode ? *pKeyCode
+			: pCharCode ? *pCharCode
+			: 0;
 
-		if (pCharCode)
-		{
-			return *pCharCode;
-		}
+		return MapKeyCode(KeyCode);
+	}
 
-		return 0;
+	ImGuiKey GetKeyIndex(const FKeyEvent& KeyEvent)
+	{
+		return MapKeyCode(KeyEvent.GetKeyCode());
 	}
 
 	uint32 GetMouseIndex(const FKey& MouseButton)
@@ -191,7 +305,9 @@ namespace ImGuiInterops
 			}
 		}
 	}
-
+	
+	// TODO: Update gamepad navigation to use new ImGuiKey API
+	/*
 	void SetGamepadNavigationKey(ImGuiTypes::FNavInputArray& NavInputs, const FKey& Key, bool bIsDown)
 	{
 #define MAP_KEY(KeyCondition, NavIndex) UpdateKey(Key, KeyCondition, NavInputs[NavIndex], bIsDown)
@@ -221,12 +337,13 @@ namespace ImGuiInterops
 
 		if (Key.IsGamepadKey())
 		{
-			MAP_SYMMETRIC_AXIS(EKeys::Gamepad_LeftX, ImGuiNavInput_LStickLeft, ImGuiNavInput_LStickRight);
-			MAP_SYMMETRIC_AXIS(EKeys::Gamepad_LeftY, ImGuiNavInput_LStickDown, ImGuiNavInput_LStickUp);
+			MAP_SYMMETRIC_AXIS(EKeys::Gamepad_LeftX, ImGuiKey_GamepadLStickLeft, ImGuiKey_GamepadLStickRight);
+			MAP_SYMMETRIC_AXIS(EKeys::Gamepad_LeftY, ImGuiKey_GamepadLStickDown, ImGuiKey_GamepadLStickUp);
 		}
 
 #undef MAP_SYMMETRIC_AXIS
 	}
+	*/
 
 	//====================================================================================================
 	// Input State Copying
@@ -247,16 +364,6 @@ namespace ImGuiInterops
 		static const uint32 LeftAlt = GetKeyIndex(EKeys::LeftAlt);
 		static const uint32 RightAlt = GetKeyIndex(EKeys::RightAlt);
 
-		// Check whether we need to draw cursor.
-		IO.MouseDrawCursor = InputState.HasMousePointer();
-
-		// Copy mouse position.
-		IO.MousePos.x = InputState.GetMousePosition().X;
-		IO.MousePos.y = InputState.GetMousePosition().Y;
-
-		// Copy mouse wheel delta.
-		IO.MouseWheel += InputState.GetMouseWheelDelta();
-
 		// Copy key modifiers.
 		IO.KeyCtrl = InputState.IsControlDown();
 		IO.KeyShift = InputState.IsShiftDown();
@@ -266,26 +373,84 @@ namespace ImGuiInterops
 		// Copy buffers.
 		if (!InputState.GetKeysUpdateRange().IsEmpty())
 		{
-			Copy(InputState.GetKeys(), IO.KeysDown, InputState.GetKeysUpdateRange());
+			// Key down events
+			for(const auto& Pair : InputState.KeyDownEvents)
+			{
+				if(UnrealToImGuiKeyMap.Contains(Pair.Value.GetKey()))
+				{
+					IO.AddKeyEvent(UnrealToImGuiKeyMap[Pair.Value.GetKey()], true);
+				}
+			}
+
+			// Key up events
+			for(const auto& Pair : InputState.KeyUpEvents)
+			{
+				if(UnrealToImGuiKeyMap.Contains(Pair.Value.GetKey()))
+				{
+					IO.AddKeyEvent(UnrealToImGuiKeyMap[Pair.Value.GetKey()], false);
+				}
+			}
 		}
 
 		if (!InputState.GetMouseButtonsUpdateRange().IsEmpty())
 		{
-			Copy(InputState.GetMouseButtons(), IO.MouseDown, InputState.GetMouseButtonsUpdateRange());
+			for(const auto& Pair : InputState.MouseButtonDownEvents)
+			{
+				uint32 MouseIdx = GetMouseIndex(Pair.Value.GetEffectingButton());
+				if(MouseIdx != -1)
+				{
+					IO.AddMouseButtonEvent(MouseIdx, true);
+				}
+			}
+			
+			
+			for(const auto& Pair : InputState.MouseButtonUpEvents)
+			{
+				uint32 MouseIdx = GetMouseIndex(Pair.Value.GetEffectingButton());
+				if(MouseIdx != -1)
+				{
+					IO.AddMouseButtonEvent(MouseIdx, false);
+				}
+			}
 		}
 
-		if (InputState.GetCharactersNum() > 0)
+		for (const TCHAR Char : InputState.GetCharacters())
 		{
-			Copy(InputState.GetCharacters(), IO.InputCharacters);
+			IO.AddInputCharacter(CastInputChar(Char));
 		}
 
+		// TODO: Update gamepad navigation to use new ImGuiKey API
+		/*
 		if (InputState.IsGamepadNavigationEnabled() && InputState.HasGamepad())
 		{
 			Copy(InputState.GetNavigationInputs(), IO.NavInputs);
 		}
+		*/
 
 		SetFlag(IO.ConfigFlags, ImGuiConfigFlags_NavEnableKeyboard, InputState.IsKeyboardNavigationEnabled());
 		SetFlag(IO.ConfigFlags, ImGuiConfigFlags_NavEnableGamepad, InputState.IsGamepadNavigationEnabled());
 		SetFlag(IO.BackendFlags, ImGuiBackendFlags_HasGamepad, InputState.HasGamepad());
+		SetFlag(IO.ConfigFlags, ImGuiConfigFlags_DockingEnable, FImGuiModule::Get().GetProperties().IsDockingEnabled());
+		
+		// Check whether we need to draw cursor.
+		IO.MouseDrawCursor = InputState.HasMousePointer();
+
+		// If touch is enabled and active, give it a precedence.
+		if (InputState.IsTouchActive())
+		{
+			// Copy the touch position to mouse position.
+			IO.AddMousePosEvent(InputState.GetTouchPosition().X, InputState.GetTouchPosition().Y);
+
+			// With touch active one frame longer than it is down, we have one frame to processed touch up.
+			IO.AddMouseButtonEvent(0, InputState.IsTouchDown());
+		}
+		else
+		{
+			// Copy the mouse position.
+			IO.AddMousePosEvent(InputState.GetMousePosition().X, InputState.GetMousePosition().Y);
+
+			// Copy mouse wheel delta.
+			IO.AddMouseWheelEvent(0, IO.MouseWheel + InputState.GetMouseWheelDelta());
+		}
 	}
 }

Source/ImGui/Private/ImGuiInteroperability.h

@@ -4,7 +4,8 @@
 
 #include "TextureManager.h"
 
-#include <ICursor.h>
+#include <GenericPlatform/ICursor.h>
+#include <Input/Events.h>
 
 #include <imgui.h>
 
@@ -21,15 +22,11 @@ namespace ImGuiInterops
 	namespace ImGuiTypes
 	{
 		using FMouseButtonsArray = decltype(ImGuiIO::MouseDown);
-		using FKeysArray = decltype(ImGuiIO::KeysDown);
-		using FNavInputArray = decltype(ImGuiIO::NavInputs);
-
-		using FInputCharactersBuffer = decltype(ImGuiIO::InputCharacters);
-
-		using FKeyMap = decltype(ImGuiIO::KeyMap);
+		// ImGuiKeyData type keeps track of down state, duration, etc. but we only care about down state
+		using FKeysArray = bool[ImGuiKey_NamedKey_COUNT];
 	}
 
-
+	
 	//====================================================================================================
 	// Input Mapping
 	//====================================================================================================
@@ -38,13 +35,10 @@ namespace ImGuiInterops
 	void SetUnrealKeyMap(ImGuiIO& IO);
 
 	// Map FKey to index in keys buffer.
-	uint32 GetKeyIndex(const FKey& Key);
+	ImGuiKey GetKeyIndex(const FKey& Key);
 
 	// Map key event to index in keys buffer.
-	FORCEINLINE uint32 GetKeyIndex(const FKeyEvent& KeyEvent)
-	{
-		return KeyEvent.GetKeyCode();
-	}
+	ImGuiKey GetKeyIndex(const FKeyEvent& KeyEvent);
 
 	// Map mouse FKey to index in mouse buttons buffer.
 	uint32 GetMouseIndex(const FKey& MouseButton);
@@ -58,6 +52,8 @@ namespace ImGuiInterops
 	// Convert from ImGuiMouseCursor type to EMouseCursor.
 	EMouseCursor::Type ToSlateMouseCursor(ImGuiMouseCursor MouseCursor);
 
+	// TODO: Update gamepad navigation to use new ImGuiKey API
+	/*
 	// Set in the target array navigation input corresponding to gamepad key.
 	// @param NavInputs - Target array
 	// @param Key - Gamepad key mapped to navigation input (non-mapped keys will be ignored)
@@ -69,7 +65,7 @@ namespace ImGuiInterops
 	// @param Key - Gamepad axis key mapped to navigation input (non-axis or non-mapped inputs will be ignored)
 	// @param Value - Axis value (-1..1 values from Unreal are mapped to separate ImGui axes with values in range 0..1)
 	void SetGamepadNavigationAxis(ImGuiTypes::FNavInputArray& NavInputs, const FKey& Key, float Value);
-
+	*/
 
 	//====================================================================================================
 	// Input State Copying
@@ -108,12 +104,12 @@ namespace ImGuiInterops
 	// Convert from ImGui Texture Id to Texture Index that we use for texture resources.
 	FORCEINLINE TextureIndex ToTextureIndex(ImTextureID Index)
 	{
-		return static_cast<TextureIndex>(reinterpret_cast<intptr_t>(Index));
+		return static_cast<TextureIndex>(static_cast<intptr_t>(Index));
 	}
 
 	// Convert from Texture Index to ImGui Texture Id that we pass to ImGui.
 	FORCEINLINE ImTextureID ToImTextureID(TextureIndex Index)
 	{
-		return reinterpret_cast<ImTextureID>(static_cast<intptr_t>(Index));
+		return static_cast<ImTextureID>(static_cast<intptr_t>(Index));
 	}
 }

Source/ImGui/Private/ImGuiModule.cpp

@@ -1,11 +1,9 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
-#include "ImGuiModuleManager.h"
+#include "ImGuiModule.h"
 
 #include "ImGuiDelegatesContainer.h"
-#include "ImGuiTextureHandle.h"
+#include "ImGuiModuleManager.h"
 #include "TextureManager.h"
 #include "Utilities/WorldContext.h"
 #include "Utilities/WorldContextIndex.h"
@@ -15,9 +13,7 @@
 #include "Editor/ImGuiEditor.h"
 #endif
 
-#include <IPluginManager.h>
-
-#define IMGUI_REDIRECT_OBSOLETE_DELEGATES 1
+#include <Interfaces/IPluginManager.h>
 
 
 #define LOCTEXT_NAMESPACE "FImGuiModule"
@@ -35,7 +31,7 @@ struct EDelegateCategory
 	};
 };
 
-static FImGuiModuleManager* ImGuiModuleManager = nullptr;
+FImGuiModuleManager* ImGuiModuleManager = nullptr;
 
 #if WITH_EDITOR
 static FImGuiEditor* ImGuiEditor = nullptr;
@@ -46,62 +42,30 @@ static FImGuiEditor* ImGuiEditor = nullptr;
 #if WITH_EDITOR
 FImGuiDelegateHandle FImGuiModule::AddEditorImGuiDelegate(const FImGuiDelegate& Delegate)
 {
-#if IMGUI_REDIRECT_OBSOLETE_DELEGATES
 	return { FImGuiDelegatesContainer::Get().OnWorldDebug(Utilities::EDITOR_CONTEXT_INDEX).Add(Delegate),
 		EDelegateCategory::Default, Utilities::EDITOR_CONTEXT_INDEX };
-#else
-	checkf(ImGuiModuleManager, TEXT("Null pointer to internal module implementation. Is module available?"));
-
-	return { ImGuiModuleManager->GetContextManager().GetEditorContextProxy().OnDraw().Add(Delegate),
-		EDelegateCategory::Default, Utilities::EDITOR_CONTEXT_INDEX };
-#endif // IMGUI_REDIRECT_OBSOLETE_DELEGATES
 }
 #endif
 
 FImGuiDelegateHandle FImGuiModule::AddWorldImGuiDelegate(const FImGuiDelegate& Delegate)
 {
-#if IMGUI_REDIRECT_OBSOLETE_DELEGATES
 	const int32 ContextIndex = Utilities::GetWorldContextIndex((UWorld*)GWorld);
 	return { FImGuiDelegatesContainer::Get().OnWorldDebug(ContextIndex).Add(Delegate), EDelegateCategory::Default, ContextIndex };
-#else
-	checkf(ImGuiModuleManager, TEXT("Null pointer to internal module implementation. Is module available?"));
+}
 
-#if WITH_EDITOR
-	checkf(GEngine, TEXT("Null GEngine. AddWorldImGuiDelegate should be only called with GEngine initialized."));
-
-	const FWorldContext* WorldContext = Utilities::GetWorldContext(GEngine->GameViewport);
-	if (!WorldContext)
-	{
-		WorldContext = Utilities::GetWorldContextFromNetMode(ENetMode::NM_DedicatedServer);
-	}
-
-	checkf(WorldContext, TEXT("Couldn't find current world. AddWorldImGuiDelegate should be only called from a valid world."));
-
-	int32 Index;
-	FImGuiContextProxy& Proxy = ImGuiModuleManager->GetContextManager().GetWorldContextProxy(*WorldContext->World(), Index);
-#else
-	const int32 Index = Utilities::STANDALONE_GAME_CONTEXT_INDEX;
-	FImGuiContextProxy& Proxy = ImGuiModuleManager->GetContextManager().GetWorldContextProxy();
-#endif
-
-	return{ Proxy.OnDraw().Add(Delegate), EDelegateCategory::Default, Index };
-#endif // IMGUI_REDIRECT_OBSOLETE_DELEGATES
+FImGuiDelegateHandle FImGuiModule::AddWorldImGuiDelegate(const UWorld* World, const FImGuiDelegate& Delegate)
+{
+	const int32 ContextIndex = Utilities::GetWorldContextIndex(World);
+	return { FImGuiDelegatesContainer::Get().OnWorldDebug(ContextIndex).Add(Delegate), EDelegateCategory::Default, ContextIndex };
 }
 
 FImGuiDelegateHandle FImGuiModule::AddMultiContextImGuiDelegate(const FImGuiDelegate& Delegate)
 {
-#if IMGUI_REDIRECT_OBSOLETE_DELEGATES
 	return { FImGuiDelegatesContainer::Get().OnMultiContextDebug().Add(Delegate), EDelegateCategory::MultiContext };
-#else
-	checkf(ImGuiModuleManager, TEXT("Null pointer to internal module implementation. Is module available?"));
-
-	return { ImGuiModuleManager->GetContextManager().OnDrawMultiContext().Add(Delegate), EDelegateCategory::MultiContext };
-#endif
 }
 
 void FImGuiModule::RemoveImGuiDelegate(const FImGuiDelegateHandle& Handle)
 {
-#if IMGUI_REDIRECT_OBSOLETE_DELEGATES
 	if (Handle.Category == EDelegateCategory::MultiContext)
 	{
 		FImGuiDelegatesContainer::Get().OnMultiContextDebug().Remove(Handle.Handle);
@@ -110,19 +74,6 @@ void FImGuiModule::RemoveImGuiDelegate(const FImGuiDelegateHandle& Handle)
 	{
 		FImGuiDelegatesContainer::Get().OnWorldDebug(Handle.Index).Remove(Handle.Handle);
 	}
-#else
-	if (ImGuiModuleManager)
-	{
-		if (Handle.Category == EDelegateCategory::MultiContext)
-		{
-			ImGuiModuleManager->GetContextManager().OnDrawMultiContext().Remove(Handle.Handle);
-		}
-		else if (auto* Proxy = ImGuiModuleManager->GetContextManager().GetContextProxy(Handle.Index))
-		{
-			Proxy->OnDraw().Remove(Handle.Handle);
-		}
-	}
-#endif
 }
 
 #endif // IMGUI_WITH_OBSOLETE_DELEGATES
@@ -133,9 +84,15 @@ FImGuiTextureHandle FImGuiModule::FindTextureHandle(const FName& Name)
 	return (Index != INDEX_NONE) ? FImGuiTextureHandle{ Name, ImGuiInterops::ToImTextureID(Index) } : FImGuiTextureHandle{};
 }
 
-FImGuiTextureHandle FImGuiModule::RegisterTexture(const FName& Name, class UTexture2D* Texture, bool bMakeUnique)
+FImGuiTextureHandle FImGuiModule::RegisterTexture(const FName& Name, class UTexture* Texture, bool bMakeUnique)
 {
-	const TextureIndex Index = ImGuiModuleManager->GetTextureManager().CreateTextureResources(Name, Texture, bMakeUnique);
+	FTextureManager& TextureManager = ImGuiModuleManager->GetTextureManager();
+
+	checkf(!bMakeUnique || TextureManager.FindTextureIndex(Name) == INDEX_NONE,
+		TEXT("Trying to register a texture with a name '%s' that is already used. Chose a different name ")
+		TEXT("or use bMakeUnique false, to update existing texture resources."), *Name.ToString());
+
+	const TextureIndex Index = TextureManager.CreateTextureResources(Name, Texture);
 	return FImGuiTextureHandle{ Name, ImGuiInterops::ToImTextureID(Index) };
 }
 
@@ -147,8 +104,28 @@ void FImGuiModule::ReleaseTexture(const FImGuiTextureHandle& Handle)
 	}
 }
 
+void FImGuiModule::RebuildFontAtlas()
+{
+	if (ImGuiModuleManager)
+	{
+		ImGuiModuleManager->RebuildFontAtlas();
+	}
+}
+
 void FImGuiModule::StartupModule()
 {
+	// Initialize handles to allow cross-module redirections. Other handles will always look for parents in the active
+	// module, which means that we can only redirect to started modules. We don't have to worry about self-referencing
+	// as local handles are guaranteed to be constructed before initializing pointers.
+	// This supports in-editor recompilation and hot-reloading after compiling from the command line. The latter method
+	// theoretically doesn't support plug-ins and will not load re-compiled module, but its handles will still redirect
+	// to the active one.
+
+#if WITH_EDITOR
+	ImGuiContextHandle = &ImGuiImplementation::GetContextHandle();
+	DelegatesContainerHandle = &FImGuiDelegatesContainer::GetHandle();
+#endif
+
 	// Create managers that implements module logic.
 
 	checkf(!ImGuiModuleManager, TEXT("Instance of the ImGui Module Manager already exists. Instance should be created only during module startup."));
@@ -197,10 +174,17 @@ void FImGuiModule::ShutdownModule()
 			FImGuiModule& LoadedModule = FImGuiModule::Get();
 			if (&LoadedModule != this)
 			{
-				// Statically bound functions will be still made to the obsolete module so we need to  
-				ImGuiImplementation::SetImGuiContextHandle(LoadedModule.GetImGuiContextHandle());
+				// Statically bound functions can be bound to the obsolete module, so we need to manually redirect.
 
-				FImGuiDelegatesContainer::MoveContainer(LoadedModule.GetDelegatesContainer());
+				if (LoadedModule.ImGuiContextHandle)
+				{
+					ImGuiImplementation::SetParentContextHandle(*LoadedModule.ImGuiContextHandle);
+				}
+
+				if (LoadedModule.DelegatesContainerHandle)
+				{
+					FImGuiDelegatesContainer::MoveContainer(*LoadedModule.DelegatesContainerHandle);
+				}
 
 				if (bMoveProperties)
 				{
@@ -218,16 +202,6 @@ void FImGuiModule::SetProperties(const FImGuiModuleProperties& Properties)
 {
 	ImGuiModuleManager->GetProperties() = Properties;
 }
-
-ImGuiContext** FImGuiModule::GetImGuiContextHandle()
-{
-	return ImGuiImplementation::GetImGuiContextHandle();
-}
-
-FImGuiDelegatesContainer& FImGuiModule::GetDelegatesContainer()
-{
-	return FImGuiDelegatesContainer::Get();
-}
 #endif
 
 FImGuiModuleProperties& FImGuiModule::GetProperties()

Source/ImGui/Private/ImGuiModuleCommands.cpp

@@ -1,9 +1,8 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiModuleCommands.h"
 
+#include "ImGuiModuleProperties.h"
 #include "Utilities/DebugExecBindings.h"
 
 
@@ -12,6 +11,9 @@ const TCHAR* const FImGuiModuleCommands::ToggleKeyboardNavigation = TEXT("ImGui.
 const TCHAR* const FImGuiModuleCommands::ToggleGamepadNavigation = TEXT("ImGui.ToggleGamepadNavigation");
 const TCHAR* const FImGuiModuleCommands::ToggleKeyboardInputSharing = TEXT("ImGui.ToggleKeyboardInputSharing");
 const TCHAR* const FImGuiModuleCommands::ToggleGamepadInputSharing = TEXT("ImGui.ToggleGamepadInputSharing");
+const TCHAR* const FImGuiModuleCommands::ToggleMouseInputSharing = TEXT("ImGui.ToggleMouseInputSharing");
+const TCHAR* const FImGuiModuleCommands::ToggleDockingEnabled = TEXT("ImGui.ToggleDockingEnabled");
+const TCHAR* const FImGuiModuleCommands::SetMouseInputSharing = TEXT("ImGui.SetMouseInputSharing");
 const TCHAR* const FImGuiModuleCommands::ToggleDemo = TEXT("ImGui.ToggleDemo");
 
 FImGuiModuleCommands::FImGuiModuleCommands(FImGuiModuleProperties& InProperties)
@@ -31,6 +33,15 @@ FImGuiModuleCommands::FImGuiModuleCommands(FImGuiModuleProperties& InProperties)
 	, ToggleGamepadInputSharingCommand(ToggleGamepadInputSharing,
 		TEXT("Toggle ImGui gamepad input sharing."),
 		FConsoleCommandDelegate::CreateRaw(this, &FImGuiModuleCommands::ToggleGamepadInputSharingImpl))
+	, ToggleMouseInputSharingCommand(ToggleMouseInputSharing,
+		TEXT("Toggle ImGui mouse input sharing."),
+		FConsoleCommandDelegate::CreateRaw(this, &FImGuiModuleCommands::ToggleMouseInputSharingImpl))
+	, ToggleDockingEnabledCommand(ToggleDockingEnabled,
+		TEXT("Toggle ImGui docking."),
+		FConsoleCommandDelegate::CreateRaw(this, &FImGuiModuleCommands::ToggleDockingEnabledImpl))
+	, SetMouseInputSharingCommand(SetMouseInputSharing,
+		TEXT("Toggle ImGui mouse input sharing."),
+		FConsoleCommandWithArgsDelegate::CreateRaw(this, &FImGuiModuleCommands::SetMouseInputSharingImpl))
 	, ToggleDemoCommand(ToggleDemo,
 		TEXT("Toggle ImGui demo."),
 		FConsoleCommandDelegate::CreateRaw(this, &FImGuiModuleCommands::ToggleDemoImpl))
@@ -67,6 +78,26 @@ void FImGuiModuleCommands::ToggleGamepadInputSharingImpl()
 	Properties.ToggleGamepadInputSharing();
 }
 
+void FImGuiModuleCommands::ToggleMouseInputSharingImpl()
+{
+	Properties.ToggleMouseInputSharing();
+}
+
+void FImGuiModuleCommands::ToggleDockingEnabledImpl()
+{
+	Properties.ToggleDockingEnabled();
+}
+
+void FImGuiModuleCommands::SetMouseInputSharingImpl(const TArray<FString>& Args)
+{
+	bool bIsEnabled = false;
+	if (Args.Num() > 0)
+	{
+		LexFromString(bIsEnabled, *Args[0]);
+	}
+	Properties.SetMouseInputShared(bIsEnabled);
+}
+
 void FImGuiModuleCommands::ToggleDemoImpl()
 {
 	Properties.ToggleDemo();

Source/ImGui/Private/ImGuiModuleCommands.h

@@ -2,7 +2,7 @@
 
 #pragma once
 
-#include <IConsoleManager.h>
+#include <HAL/IConsoleManager.h>
 
 
 struct FImGuiKeyInfo;
@@ -18,6 +18,9 @@ public:
 	static const TCHAR* const ToggleGamepadNavigation;
 	static const TCHAR* const ToggleKeyboardInputSharing;
 	static const TCHAR* const ToggleGamepadInputSharing;
+	static const TCHAR* const ToggleMouseInputSharing;
+	static const TCHAR* const ToggleDockingEnabled;
+	static const TCHAR* const SetMouseInputSharing;
 	static const TCHAR* const ToggleDemo;
 
 	FImGuiModuleCommands(FImGuiModuleProperties& InProperties);
@@ -31,6 +34,9 @@ private:
 	void ToggleGamepadNavigationImpl();
 	void ToggleKeyboardInputSharingImpl();
 	void ToggleGamepadInputSharingImpl();
+	void ToggleMouseInputSharingImpl();
+	void ToggleDockingEnabledImpl();
+	void SetMouseInputSharingImpl(const TArray< FString >& Args);
 	void ToggleDemoImpl();
 
 	FImGuiModuleProperties& Properties;
@@ -40,5 +46,8 @@ private:
 	FAutoConsoleCommand ToggleGamepadNavigationCommand;
 	FAutoConsoleCommand ToggleKeyboardInputSharingCommand;
 	FAutoConsoleCommand ToggleGamepadInputSharingCommand;
+	FAutoConsoleCommand ToggleMouseInputSharingCommand;
+	FAutoConsoleCommand ToggleDockingEnabledCommand;
+	FAutoConsoleCommand SetMouseInputSharingCommand;
 	FAutoConsoleCommand ToggleDemoCommand;
 };

Source/ImGui/Private/ImGuiModuleManager.cpp

@@ -1,13 +1,12 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiModuleManager.h"
 
 #include "ImGuiInteroperability.h"
 #include "Utilities/WorldContextIndex.h"
 
-#include <ModuleManager.h>
+#include <Framework/Application/SlateApplication.h>
+#include <Modules/ModuleManager.h>
 
 #include <imgui.h>
 
@@ -15,14 +14,18 @@
 // High enough z-order guarantees that ImGui output is rendered on top of the game UI.
 constexpr int32 IMGUI_WIDGET_Z_ORDER = 10000;
 
+// Module texture names.
+const static FName PlainTextureName = "ImGuiModule_Plain";
+const static FName FontAtlasTextureName = "ImGuiModule_FontAtlas";
 
 FImGuiModuleManager::FImGuiModuleManager()
 	: Commands(Properties)
 	, Settings(Properties, Commands)
 	, ImGuiDemo(Properties)
+	, ContextManager(Settings)
 {
 	// Register in context manager to get information whenever a new context proxy is created.
-	ContextManager.OnContextProxyCreated().AddRaw(this, &FImGuiModuleManager::OnContextProxyCreated);
+	ContextManager.OnContextProxyCreated.AddRaw(this, &FImGuiModuleManager::OnContextProxyCreated);
 
 	// Typically we will use viewport created events to add widget to new game viewports.
 	ViewportCreatedHandle = UGameViewportClient::OnViewportCreated().AddRaw(this, &FImGuiModuleManager::OnViewportCreated);
@@ -43,6 +46,8 @@ FImGuiModuleManager::FImGuiModuleManager()
 
 FImGuiModuleManager::~FImGuiModuleManager()
 {
+	ContextManager.OnFontAtlasBuilt.RemoveAll(this);
+
 	// We are no longer interested with adding widgets to viewports.
 	if (ViewportCreatedHandle.IsValid())
 	{
@@ -69,6 +74,11 @@ FImGuiModuleManager::~FImGuiModuleManager()
 	UnregisterTick();
 }
 
+void FImGuiModuleManager::RebuildFontAtlas()
+{
+	ContextManager.RebuildFontAtlas();
+}
+
 void FImGuiModuleManager::LoadTextures()
 {
 	checkf(FSlateApplication::IsInitialized(), TEXT("Slate should be initialized before we can create textures."));
@@ -80,22 +90,30 @@ void FImGuiModuleManager::LoadTextures()
 		TextureManager.InitializeErrorTexture(FColor::Magenta);
 
 		// Create an empty texture at index 0. We will use it for ImGui outputs with null texture id.
-		TextureManager.CreatePlainTexture(FName{ "ImGuiModule_Plain" }, 2, 2, FColor::White);
+		TextureManager.CreatePlainTexture(PlainTextureName, 2, 2, FColor::White);
 
-		// Create a font atlas texture.
-		ImFontAtlas& Fonts = ContextManager.GetFontAtlas();
+		// Register for atlas built events, so we can rebuild textures.
+		ContextManager.OnFontAtlasBuilt.AddRaw(this, &FImGuiModuleManager::BuildFontAtlasTexture);
 
-		unsigned char* Pixels;
-		int Width, Height, Bpp;
-		Fonts.GetTexDataAsRGBA32(&Pixels, &Width, &Height, &Bpp);
-
-		TextureIndex FontsTexureIndex = TextureManager.CreateTexture(FName{ "ImGuiModule_FontAtlas" }, Width, Height, Bpp, Pixels);
-
-		// Set font texture index in ImGui.
-		Fonts.TexID = ImGuiInterops::ToImTextureID(FontsTexureIndex);
+		BuildFontAtlasTexture();
 	}
 }
 
+void FImGuiModuleManager::BuildFontAtlasTexture()
+{
+	// Create a font atlas texture.
+	ImFontAtlas& Fonts = ContextManager.GetFontAtlas();
+
+	unsigned char* Pixels;
+	int Width, Height, Bpp;
+	Fonts.GetTexDataAsRGBA32(&Pixels, &Width, &Height, &Bpp);
+
+	const TextureIndex FontsTexureIndex = TextureManager.CreateTexture(FontAtlasTextureName, Width, Height, Bpp, Pixels);
+
+	// Set the font texture index in the ImGui.
+	Fonts.TexID = ImGuiInterops::ToImTextureID(FontsTexureIndex);
+}
+
 void FImGuiModuleManager::RegisterTick()
 {
 	// Slate Post-Tick is a good moment to end and advance ImGui frame as it minimises a tearing.
@@ -147,16 +165,9 @@ void FImGuiModuleManager::ReleaseTickInitializer()
 	}
 }
 
-bool FImGuiModuleManager::IsInUpdateThread()
-{
-	// We can get ticks from the Game thread and Slate loading thread. In both cases IsInGameThread() is true, so we
-	// need to make additional test to filter out loading thread.
-	return IsInGameThread() && !IsInSlateThread();
-}
-
 void FImGuiModuleManager::Tick(float DeltaSeconds)
 {
-	if (IsInUpdateThread())
+	if (IsInGameThread())
 	{
 		// Update context manager to advance all ImGui contexts to the next frame.
 		ContextManager.Tick(DeltaSeconds);

Source/ImGui/Private/ImGuiModuleManager.h

@@ -34,6 +34,8 @@ public:
 	// Event called right after ImGui is updated, to give other subsystems chance to react.
 	FSimpleMulticastDelegate& OnPostImGuiUpdate() { return PostImGuiUpdateEvent; }
 
+	void RebuildFontAtlas();
+
 private:
 
 	FImGuiModuleManager();
@@ -46,6 +48,7 @@ private:
 	FImGuiModuleManager& operator=(FImGuiModuleManager&&) = delete;
 
 	void LoadTextures();
+	void BuildFontAtlasTexture();
 
 	bool IsTickRegistered() { return TickDelegateHandle.IsValid(); }
 	void RegisterTick();
@@ -54,8 +57,6 @@ private:
 	void CreateTickInitializer();
 	void ReleaseTickInitializer();
 
-	bool IsInUpdateThread();
-
 	void Tick(float DeltaSeconds);
 
 	void OnViewportCreated();

Source/ImGui/Private/ImGuiModuleSettings.cpp

@@ -1,12 +1,45 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiModuleSettings.h"
 
 #include "ImGuiModuleCommands.h"
 #include "ImGuiModuleProperties.h"
 
+#include <Engine/Engine.h>
+#include <GameFramework/GameUserSettings.h>
+#include <Misc/ConfigCacheIni.h>
+
+
+//====================================================================================================
+// FImGuiDPIScaleInfo
+//====================================================================================================
+
+FImGuiDPIScaleInfo::FImGuiDPIScaleInfo()
+{
+	if (FRichCurve* Curve = DPICurve.GetRichCurve())
+	{
+		Curve->AddKey(   0.0f, 1.f);
+
+		Curve->AddKey(2159.5f, 1.f);
+		Curve->AddKey(2160.0f, 2.f);
+
+		Curve->AddKey(4319.5f, 2.f);
+		Curve->AddKey(4320.0f, 4.f);
+	}
+}
+
+float FImGuiDPIScaleInfo::CalculateResolutionBasedScale() const
+{
+	float ResolutionBasedScale = 1.f;
+	if (bScaleWithCurve && GEngine && GEngine->GameUserSettings)
+	{
+		if (const FRichCurve* Curve = DPICurve.GetRichCurveConst())
+		{
+			ResolutionBasedScale *= Curve->Eval((float)GEngine->GameUserSettings->GetDesktopResolution().Y, 1.f);
+		}
+	}
+	return ResolutionBasedScale;
+}
 
 //====================================================================================================
 // UImGuiSettings
@@ -20,32 +53,6 @@ void UImGuiSettings::PostInitProperties()
 {
 	Super::PostInitProperties();
 
-	if (SwitchInputModeKey_DEPRECATED.Key.IsValid() && !ToggleInput.Key.IsValid())
-	{
-		const FString ConfigFileName = GetDefaultConfigFilename();
-
-		// Move value to the new property.
-		ToggleInput = MoveTemp(SwitchInputModeKey_DEPRECATED);
-
-		// Remove from configuration file entry for obsolete property.
-		if (FConfigFile* ConfigFile = GConfig->Find(ConfigFileName, false))
-		{
-			if (FConfigSection* Section = ConfigFile->Find(TEXT("/Script/ImGui.ImGuiSettings")))
-			{
-				if (Section->Remove(TEXT("SwitchInputModeKey")))
-				{
-					ConfigFile->Dirty = true;
-					GConfig->Flush(false, ConfigFileName);
-				}
-			}
-		}
-
-		// Add to configuration file entry for new property.
-		UpdateSinglePropertyInConfigFile(
-			UImGuiSettings::StaticClass()->FindPropertyByName(GET_MEMBER_NAME_CHECKED(UImGuiSettings, ToggleInput)),
-			ConfigFileName);
-	}
-
 	if (IsTemplate())
 	{
 		DefaultInstance = this;
@@ -77,10 +84,10 @@ FImGuiModuleSettings::FImGuiModuleSettings(FImGuiModuleProperties& InProperties,
 
 	// Delegate initializer to support settings loaded after this object creation (in stand-alone builds) and potential
 	// reloading of settings.
-	UImGuiSettings::OnSettingsLoaded.AddRaw(this, &FImGuiModuleSettings::UpdateSettings);
+	UImGuiSettings::OnSettingsLoaded.AddRaw(this, &FImGuiModuleSettings::InitializeAllSettings);
 
 	// Call initializer to support settings already loaded (editor).
-	UpdateSettings();
+	InitializeAllSettings();
 }
 
 FImGuiModuleSettings::~FImGuiModuleSettings()
@@ -93,6 +100,12 @@ FImGuiModuleSettings::~FImGuiModuleSettings()
 #endif
 }
 
+void FImGuiModuleSettings::InitializeAllSettings()
+{
+	UpdateSettings();
+	UpdateDPIScaleInfo();
+}
+
 void FImGuiModuleSettings::UpdateSettings()
 {
 	if (UImGuiSettings* SettingsObject = UImGuiSettings::Get())
@@ -100,12 +113,22 @@ void FImGuiModuleSettings::UpdateSettings()
 		SetImGuiInputHandlerClass(SettingsObject->ImGuiInputHandlerClass);
 		SetShareKeyboardInput(SettingsObject->bShareKeyboardInput);
 		SetShareGamepadInput(SettingsObject->bShareGamepadInput);
+		SetShareMouseInput(SettingsObject->bShareMouseInput);
 		SetUseSoftwareCursor(SettingsObject->bUseSoftwareCursor);
 		SetToggleInputKey(SettingsObject->ToggleInput);
+		SetCanvasSizeInfo(SettingsObject->CanvasSize);
 	}
 }
 
-void FImGuiModuleSettings::SetImGuiInputHandlerClass(const FStringClassReference& ClassReference)
+void FImGuiModuleSettings::UpdateDPIScaleInfo()
+{
+	if (UImGuiSettings* SettingsObject = UImGuiSettings::Get())
+	{
+		SetDPIScaleInfo(SettingsObject->DPIScale);
+	}
+}
+
+void FImGuiModuleSettings::SetImGuiInputHandlerClass(const FSoftClassPath& ClassReference)
 {
 	if (ImGuiInputHandlerClass != ClassReference)
 	{
@@ -132,6 +155,15 @@ void FImGuiModuleSettings::SetShareGamepadInput(bool bShare)
 	}
 }
 
+void FImGuiModuleSettings::SetShareMouseInput(bool bShare)
+{
+	if (bShareMouseInput != bShare)
+	{
+		bShareMouseInput = bShare;
+		Properties.SetMouseInputShared(bShare);
+	}
+}
+
 void FImGuiModuleSettings::SetUseSoftwareCursor(bool bUse)
 {
 	if (bUseSoftwareCursor != bUse)
@@ -150,6 +182,30 @@ void FImGuiModuleSettings::SetToggleInputKey(const FImGuiKeyInfo& KeyInfo)
 	}
 }
 
+void FImGuiModuleSettings::SetIsDockingEnabled(bool bDockingEnabled)
+{
+	if (bIsDockingEnabled != bDockingEnabled)
+	{
+		bIsDockingEnabled = bDockingEnabled;
+		Properties.SetDockingEnabled(bDockingEnabled);
+	}
+}
+
+void FImGuiModuleSettings::SetCanvasSizeInfo(const FImGuiCanvasSizeInfo& CanvasSizeInfo)
+{
+	if (CanvasSize != CanvasSizeInfo)
+	{
+		CanvasSize = CanvasSizeInfo;
+		OnCanvasSizeChangedDelegate.Broadcast(CanvasSize);
+	}
+}
+
+void FImGuiModuleSettings::SetDPIScaleInfo(const FImGuiDPIScaleInfo& ScaleInfo)
+{
+	DPIScale = ScaleInfo;
+	OnDPIScaleChangedDelegate.Broadcast(DPIScale);
+}
+
 #if WITH_EDITOR
 
 void FImGuiModuleSettings::OnPropertyChanged(class UObject* ObjectBeingModified, struct FPropertyChangedEvent& PropertyChangedEvent)
@@ -157,6 +213,11 @@ void FImGuiModuleSettings::OnPropertyChanged(class UObject* ObjectBeingModified,
 	if (ObjectBeingModified == UImGuiSettings::Get())
 	{
 		UpdateSettings();
+		if (PropertyChangedEvent.MemberProperty
+			&& (PropertyChangedEvent.MemberProperty->GetFName() == GET_MEMBER_NAME_CHECKED(FImGuiModuleSettings, DPIScale)))
+		{
+			UpdateDPIScaleInfo();
+		}
 	}
 }
 

Source/ImGui/Private/ImGuiModuleSettings.h

@@ -2,9 +2,22 @@
 
 #pragma once
 
+#include "VersionCompatibility.h"
+
+#include <Curves/CurveFloat.h>
 #include <Delegates/Delegate.h>
+#include <InputCoreTypes.h>
+#include <Styling/SlateTypes.h>
 #include <UObject/Object.h>
 
+// We use FSoftClassPath, which is supported by older and newer engine versions. Starting from 4.18, it is
+// a typedef of FSoftClassPath, which is also recognized by UHT.
+#if ENGINE_COMPATIBILITY_LEGACY_STRING_CLASS_REF
+#include <StringClassReference.h>
+#else
+#include <UObject/SoftObjectPath.h>
+#endif
+
 #include "ImGuiModuleSettings.generated.h"
 
 
@@ -17,19 +30,19 @@ struct FImGuiKeyInfo
 {
 	GENERATED_BODY()
 
-	UPROPERTY(EditAnywhere)
+	UPROPERTY(EditAnywhere, Category = "Input")
 	FKey Key;
 
-	UPROPERTY(EditAnywhere)
+	UPROPERTY(EditAnywhere, Category = "Input")
 	ECheckBoxState Shift = ECheckBoxState::Undetermined;
 
-	UPROPERTY(EditAnywhere)
+	UPROPERTY(EditAnywhere, Category = "Input")
 	ECheckBoxState Ctrl = ECheckBoxState::Undetermined;
 
-	UPROPERTY(EditAnywhere)
+	UPROPERTY(EditAnywhere, Category = "Input")
 	ECheckBoxState Alt = ECheckBoxState::Undetermined;
 
-	UPROPERTY(EditAnywhere)
+	UPROPERTY(EditAnywhere, Category = "Input")
 	ECheckBoxState Cmd = ECheckBoxState::Undetermined;
 
 	friend bool operator==(const FImGuiKeyInfo& Lhs, const FImGuiKeyInfo& Rhs)
@@ -47,6 +60,100 @@ struct FImGuiKeyInfo
 	}
 };
 
+UENUM(BlueprintType)
+enum class EImGuiCanvasSizeType : uint8
+{
+	Custom UMETA(ToolTip = "Canvas will have a custom width and height."),
+	Desktop UMETA(ToolTip = "Canvas will have the same width and height as the desktop."),
+	Viewport UMETA(ToolTip = "Canvas will always have the same width and height as the viewport."),
+};
+
+/**
+ * Struct with information how to calculate canvas size. 
+ */
+USTRUCT()
+struct FImGuiCanvasSizeInfo
+{
+	GENERATED_BODY()
+
+	// Select how to specify canvas size.
+	UPROPERTY(EditAnywhere, Category = "Canvas Size")
+	EImGuiCanvasSizeType SizeType = EImGuiCanvasSizeType::Desktop;
+
+	// Custom canvas width.
+	UPROPERTY(EditAnywhere, Category = "Canvas Size", meta = (ClampMin = 0, UIMin = 0))
+	int32 Width = 3840;
+
+	// Custom canvas height.
+	UPROPERTY(EditAnywhere, Category = "Canvas Size", meta = (ClampMin = 0, UIMin = 0))
+	int32 Height = 2160;
+
+	// If this is true, canvas width or height may be extended, if the viewport size is larger.
+	UPROPERTY(EditAnywhere, Category = "Canvas Size", meta = (ClampMin = 0, UIMin = 0))
+	bool bExtendToViewport = true;
+
+	bool operator==(const FImGuiCanvasSizeInfo& Other) const
+	{
+		return (SizeType == Other.SizeType) && (Width == Other.Width)
+			&& (Height == Other.Height) && (bExtendToViewport == Other.bExtendToViewport);
+	}
+
+	bool operator!=(const FImGuiCanvasSizeInfo& Other) const { return !(*this == Other); }
+};
+
+UENUM(BlueprintType)
+enum class EImGuiDPIScaleMethod : uint8
+{
+	ImGui UMETA(DisplayName = "ImGui", ToolTip = "Scale ImGui fonts and styles."),
+	Slate UMETA(ToolTip = "Scale in Slate. ImGui canvas size will be adjusted to get the screen size that is the same as defined in the Canvas Size property.")
+};
+
+/**
+ * Struct with DPI scale data.
+ */
+USTRUCT()
+struct FImGuiDPIScaleInfo
+{
+	GENERATED_BODY()
+
+protected:
+
+	// Whether to scale in ImGui or in Slate. Scaling in ImGui gives better looking results but Slate might be a better
+	// option when layouts do not account for different fonts and styles. When scaling in Slate, ImGui canvas size will
+	// be adjusted to get the screen size that is the same as defined in the Canvas Size property.
+	UPROPERTY(EditAnywhere, Category = "DPI Scale")
+	EImGuiDPIScaleMethod ScalingMethod = EImGuiDPIScaleMethod::ImGui;
+
+	// An optional scale to apply on top or instead of the curve-based scale.
+	UPROPERTY(EditAnywhere, Category = "DPI Scale", meta = (ClampMin = 0, UIMin = 0))
+	float Scale = 1.f;
+
+	// Curve mapping resolution height to scale.
+	UPROPERTY(config, EditAnywhere, Category = "DPI Scale", meta = (XAxisName = "Resolution Height", YAxisName = "Scale", EditCondition = "bScaleWithCurve"))
+	FRuntimeFloatCurve DPICurve;
+
+	// Whether to use curve-based scaling. If enabled, Scale will be multiplied by a value read from the DPICurve.
+	// If disabled, only the Scale property will be used.
+	UPROPERTY(config, EditAnywhere, Category = "DPI Scale")
+	bool bScaleWithCurve = true;
+
+public:
+
+	FImGuiDPIScaleInfo();
+
+	float GetImGuiScale() const { return ShouldScaleInSlate() ? 1.f : CalculateScale(); }
+
+	float GetSlateScale() const { return ShouldScaleInSlate() ? CalculateScale() : 1.f; }
+
+	bool ShouldScaleInSlate() const { return ScalingMethod == EImGuiDPIScaleMethod::Slate; }
+
+private:
+
+	float CalculateScale() const { return Scale * CalculateResolutionBasedScale(); }
+
+	float CalculateResolutionBasedScale() const;
+};
+
 // UObject used for loading and saving ImGui settings. To access actual settings use FImGuiModuleSettings interface.
 UCLASS(config=ImGui, defaultconfig)
 class UImGuiSettings : public UObject
@@ -68,8 +175,8 @@ protected:
 
 	// Path to own implementation of ImGui Input Handler allowing to customize handling of keyboard and gamepad input.
 	// If not set then default handler is used.
-	UPROPERTY(EditAnywhere, config, Category = "Extensions", meta = (MetaClass = "ImGuiInputHandler"))
-	FStringClassReference ImGuiInputHandlerClass;
+	UPROPERTY(EditAnywhere, config, Category = "Extensions", meta = (MetaClass = "/Script/ImGui.ImGuiInputHandler"))
+	FSoftClassPath ImGuiInputHandlerClass;
 
 	// Whether ImGui should share keyboard input with game.
 	// This defines initial behaviour which can be later changed using 'ImGui.ToggleKeyboardInputSharing' command or
@@ -83,12 +190,24 @@ protected:
 	UPROPERTY(EditAnywhere, config, Category = "Input")
 	bool bShareGamepadInput = false;
 
+	// Whether ImGui should share mouse input with game.
+	// This defines initial behaviour which can be later changed using 'ImGui.ToggleMouseInputSharing' command or
+	// module properties interface.
+	UPROPERTY(EditAnywhere, config, Category = "Input")
+	bool bShareMouseInput = false;
+
+	// Whether docking should be enabled.
+	// This defines initial behaviour which can be later changed using 'ImGui.ToggleDockingEnabled' command or
+	// module properties interface.
+	UPROPERTY(EditAnywhere, config, Category = "Input", DisplayName = "Enable Docking")
+	bool bIsDockingEnabled = true;
+	
 	// If true, then in input mode ImGui will draw its own cursor in place of the hardware one.
 	// When disabled (default) there is a noticeable difference between cursor position seen by ImGui and position on
 	// the screen. Enabling this option removes that effect but with lower frame-rates UI becomes quickly unusable.
 	UPROPERTY(EditAnywhere, config, Category = "Input", AdvancedDisplay)
 	bool bUseSoftwareCursor = false;
-
+	
 	// Define a shortcut key to 'ImGui.ToggleInput' command. Binding is only set if the key field is valid.
 	// Note that modifier key properties can be set to one of the three values: undetermined means that state of the given
 	// modifier is not important, checked means that it needs to be pressed and unchecked means that it cannot be pressed.
@@ -97,9 +216,13 @@ protected:
 	UPROPERTY(EditAnywhere, config, Category = "Keyboard Shortcuts")
 	FImGuiKeyInfo ToggleInput;
 
-	// Deprecated name for ToggleInput. Kept temporarily to automatically move old configuration.
-	UPROPERTY(config)
-	FImGuiKeyInfo SwitchInputModeKey_DEPRECATED;
+	// Chose how to define the ImGui canvas size. Select between custom, desktop and viewport.
+	UPROPERTY(EditAnywhere, config, Category = "Canvas Size")
+	FImGuiCanvasSizeInfo CanvasSize;
+
+	// Setup DPI Scale.
+	UPROPERTY(EditAnywhere, config, Category = "DPI Scale", Meta = (ShowOnlyInnerProperties))
+	FImGuiDPIScaleInfo DPIScale;
 
 	static UImGuiSettings* DefaultInstance;
 
@@ -119,7 +242,9 @@ public:
 
 	// Generic delegate used to notify changes of boolean properties.
 	DECLARE_MULTICAST_DELEGATE_OneParam(FBoolChangeDelegate, bool);
-	DECLARE_MULTICAST_DELEGATE_OneParam(FStringClassReferenceChangeDelegate, const FStringClassReference&);
+	DECLARE_MULTICAST_DELEGATE_OneParam(FStringClassReferenceChangeDelegate, const FSoftClassPath&);
+	DECLARE_MULTICAST_DELEGATE_OneParam(FImGuiCanvasSizeInfoChangeDelegate, const FImGuiCanvasSizeInfo&);
+	DECLARE_MULTICAST_DELEGATE_OneParam(FImGuiDPIScaleInfoChangeDelegate, const FImGuiDPIScaleInfo&);
 
 	// Constructor for ImGui module settings. It will bind to instances of module properties and commands and will
 	// update them every time when settings are changed.
@@ -134,7 +259,7 @@ public:
 	// event that are defined depending on needs.
 
 	// Get the path to custom implementation of ImGui Input Handler.
-	const FStringClassReference& GetImGuiInputHandlerClass() const { return ImGuiInputHandlerClass; }
+	const FSoftClassPath& GetImGuiInputHandlerClass() const { return ImGuiInputHandlerClass; }
 
 	// Get the software cursor configuration.
 	bool UseSoftwareCursor() const { return bUseSoftwareCursor; }
@@ -142,21 +267,39 @@ public:
 	// Get the shortcut configuration for 'ImGui.ToggleInput' command.
 	const FImGuiKeyInfo& GetToggleInputKey() const { return ToggleInputKey; }
 
+	// Get the information how to calculate the canvas size.
+	const FImGuiCanvasSizeInfo& GetCanvasSizeInfo() const { return CanvasSize; }
+
+	// Get the DPI Scale information.
+	const FImGuiDPIScaleInfo& GetDPIScaleInfo() const { return DPIScale; }
+
 	// Delegate raised when ImGui Input Handle is changed.
 	FStringClassReferenceChangeDelegate OnImGuiInputHandlerClassChanged;
 
 	// Delegate raised when software cursor configuration is changed.
 	FBoolChangeDelegate OnUseSoftwareCursorChanged;
 
+	// Delegate raised when information how to calculate the canvas size is changed.
+	FImGuiCanvasSizeInfoChangeDelegate OnCanvasSizeChangedDelegate;
+
+	// Delegate raised when the DPI scale is changed.
+	FImGuiDPIScaleInfoChangeDelegate OnDPIScaleChangedDelegate;
+
 private:
 
+	void InitializeAllSettings();
 	void UpdateSettings();
+	void UpdateDPIScaleInfo();
 
-	void SetImGuiInputHandlerClass(const FStringClassReference& ClassReference);
+	void SetImGuiInputHandlerClass(const FSoftClassPath& ClassReference);
 	void SetShareKeyboardInput(bool bShare);
 	void SetShareGamepadInput(bool bShare);
+	void SetShareMouseInput(bool bShare);
 	void SetUseSoftwareCursor(bool bUse);
 	void SetToggleInputKey(const FImGuiKeyInfo& KeyInfo);
+	void SetIsDockingEnabled(bool bDockingEnabled);
+	void SetCanvasSizeInfo(const FImGuiCanvasSizeInfo& CanvasSizeInfo);
+	void SetDPIScaleInfo(const FImGuiDPIScaleInfo& ScaleInfo);
 
 #if WITH_EDITOR
 	void OnPropertyChanged(class UObject* ObjectBeingModified, struct FPropertyChangedEvent& PropertyChangedEvent);
@@ -165,9 +308,13 @@ private:
 	FImGuiModuleProperties& Properties;
 	FImGuiModuleCommands& Commands;
 
-	FStringClassReference ImGuiInputHandlerClass;
+	FSoftClassPath ImGuiInputHandlerClass;
 	FImGuiKeyInfo ToggleInputKey;
+	FImGuiCanvasSizeInfo CanvasSize;
+	FImGuiDPIScaleInfo DPIScale;
 	bool bShareKeyboardInput = false;
 	bool bShareGamepadInput = false;
+	bool bShareMouseInput = false;
 	bool bUseSoftwareCursor = false;
+	bool bIsDockingEnabled = true;
 };

Source/ImGui/Private/ImGuiPrivatePCH.h

@@ -1,23 +0,0 @@
-// Distributed under the MIT License (MIT) (see accompanying LICENSE file)
-
-// Module-wide macros
-#include "VersionCompatibility.h"
-#include "ImGuiModuleDebug.h"
-
-// Module
-#include "ImGuiModule.h"
-
-// Engine
-#include <Core.h>
-#include <Engine.h>
-
-// For backward compatibility we will use FStringClassReference which in newer engine versions is a typedef for
-// FSoftClassPath. Include right soft class reference header to avoid warnings in newer engine version.
-#if ENGINE_COMPATIBILITY_LEGACY_STRING_CLASS_REF
-#include <StringClassReference.h>
-#else
-#include <UObject/SoftObjectPath.h>
-#endif
-
-// You should place include statements to your module's private header files here.  You only need to
-// add includes for headers that are used in most of your module's source files though.

Source/ImGui/Private/ImGuiTextureHandle.cpp

@@ -1,7 +1,5 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "ImGuiTextureHandle.h"
 
 #include "ImGuiInteroperability.h"

Source/ImGui/Private/TextureManager.cpp

@@ -1,8 +1,9 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "TextureManager.h"
+#include "RHITypes.h"
+#include <Engine/Texture2D.h>
+#include <Framework/Application/SlateApplication.h>
 
 #include <algorithm>
 
@@ -15,7 +16,6 @@ void FTextureManager::InitializeErrorTexture(const FColor& Color)
 TextureIndex FTextureManager::CreateTexture(const FName& Name, int32 Width, int32 Height, uint32 SrcBpp, uint8* SrcData, TFunction<void(uint8*)> SrcDataCleanup)
 {
 	checkf(Name != NAME_None, TEXT("Trying to create a texture with a name 'NAME_None' is not allowed."));
-	checkf(FindTextureIndex(Name) == INDEX_NONE, TEXT("Trying to create texture using name '%s' that is already registered."), *Name.ToString());
 
 	return CreateTextureInternal(Name, Width, Height, SrcBpp, SrcData, SrcDataCleanup);
 }
@@ -23,24 +23,17 @@ TextureIndex FTextureManager::CreateTexture(const FName& Name, int32 Width, int3
 TextureIndex FTextureManager::CreatePlainTexture(const FName& Name, int32 Width, int32 Height, FColor Color)
 {
 	checkf(Name != NAME_None, TEXT("Trying to create a texture with a name 'NAME_None' is not allowed."));
-	checkf(FindTextureIndex(Name) == INDEX_NONE, TEXT("Trying to create texture using name '%s' that is already registered."), *Name.ToString());
 
 	return CreatePlainTextureInternal(Name, Width, Height, Color);
 }
 
-TextureIndex FTextureManager::CreateTextureResources(const FName& Name, UTexture2D* Texture, bool bMakeUnique)
+TextureIndex FTextureManager::CreateTextureResources(const FName& Name, UTexture* Texture)
 {
 	checkf(Name != NAME_None, TEXT("Trying to create texture resources with a name 'NAME_None' is not allowed."));
 	checkf(Texture, TEXT("Null Texture."));
 
-	if (bMakeUnique)
-	{
-		checkf(FindTextureIndex(Name) == INDEX_NONE, TEXT("Trying to create texture resources using name '%s' that is already registered.")
-			TEXT(" Consider using different name or set bMakeUnique parameter to false."), *Name.ToString());
-	}
-
 	// Create an entry for the texture.
-	return AddTextureEntry(Name, Texture, false, true);
+	return AddTextureEntry(Name, Texture, false);
 }
 
 void FTextureManager::ReleaseTextureResources(TextureIndex Index)
@@ -75,7 +68,7 @@ TextureIndex FTextureManager::CreateTextureInternal(const FName& Name, int32 Wid
 	}
 	else
 	{
-		return AddTextureEntry(Name, Texture, true, false);
+		return AddTextureEntry(Name, Texture, true);
 	}
 }
 
@@ -94,18 +87,18 @@ TextureIndex FTextureManager::CreatePlainTextureInternal(const FName& Name, int3
 	return CreateTextureInternal(Name, Width, Height, Bpp, SrcData, SrcDataCleanup);
 }
 
-TextureIndex FTextureManager::AddTextureEntry(const FName& Name, UTexture2D* Texture, bool bAddToRoot, bool bUpdate)
+TextureIndex FTextureManager::AddTextureEntry(const FName& Name, UTexture* Texture, bool bAddToRoot)
 {
-	// If we update try to find entry with that name.
-	TextureIndex Index = bUpdate ? FindTextureIndex(Name) : INDEX_NONE;
+	// Try to find an entry with that name.
+	TextureIndex Index = FindTextureIndex(Name);
 
-	// If we didn't find, try to find and entry to reuse.
+	// If this is a new name, try to find an entry to reuse.
 	if (Index == INDEX_NONE)
 	{
 		Index = FindTextureIndex(NAME_None);
 	}
 
-	// Either update/reuse entry or add a new one.
+	// Either update/reuse an entry or add a new one.
 	if (Index != INDEX_NONE)
 	{
 		TextureResources[Index] = { Name, Texture, bAddToRoot };
@@ -117,7 +110,7 @@ TextureIndex FTextureManager::AddTextureEntry(const FName& Name, UTexture2D* Tex
 	}
 }
 
-FTextureManager::FTextureEntry::FTextureEntry(const FName& InName, UTexture2D* InTexture, bool bAddToRoot)
+FTextureManager::FTextureEntry::FTextureEntry(const FName& InName, UTexture* InTexture, bool bAddToRoot)
 	: Name(InName)
 {
 	checkf(InTexture, TEXT("Null texture."));
@@ -132,7 +125,7 @@ FTextureManager::FTextureEntry::FTextureEntry(const FName& InName, UTexture2D* I
 
 	// Create brush and resource handle for input texture.
 	Brush.SetResourceObject(InTexture);
-	ResourceHandle = FSlateApplication::Get().GetRenderer()->GetResourceHandle(Brush);
+	CachedResourceHandle = FSlateApplication::Get().GetRenderer()->GetResourceHandle(Brush);
 }
 
 FTextureManager::FTextureEntry::~FTextureEntry()
@@ -149,7 +142,7 @@ FTextureManager::FTextureEntry& FTextureManager::FTextureEntry::operator=(FTextu
 	Name = MoveTemp(Other.Name);
 	Texture = MoveTemp(Other.Texture);
 	Brush = MoveTemp(Other.Brush);
-	ResourceHandle = MoveTemp(Other.ResourceHandle);
+	CachedResourceHandle = MoveTemp(Other.CachedResourceHandle);
 
 	// Reset the other entry (without releasing resources which are already moved to this instance) to remove tracks
 	// of ownership and mark it as empty/reusable.
@@ -158,6 +151,15 @@ FTextureManager::FTextureEntry& FTextureManager::FTextureEntry::operator=(FTextu
 	return *this;
 }
 
+const FSlateResourceHandle& FTextureManager::FTextureEntry::GetResourceHandle() const
+{
+	if (!CachedResourceHandle.IsValid() && Brush.HasUObject())
+	{
+		CachedResourceHandle = FSlateApplication::Get().GetRenderer()->GetResourceHandle(Brush);
+	}
+	return CachedResourceHandle;
+}
+
 void FTextureManager::FTextureEntry::Reset(bool bReleaseResources)
 {
 	if (bReleaseResources)
@@ -182,5 +184,5 @@ void FTextureManager::FTextureEntry::Reset(bool bReleaseResources)
 	// Clean fields to make sure that we don't reference released or moved resources.
 	Texture.Reset();
 	Brush = FSlateNoResource();
-	ResourceHandle = FSlateResourceHandle();
+	CachedResourceHandle = FSlateResourceHandle();
 }

Source/ImGui/Private/TextureManager.h

@@ -2,11 +2,13 @@
 
 #pragma once
 
-#include <Core.h>
 #include <Styling/SlateBrush.h>
 #include <Textures/SlateShaderResource.h>
+#include <UObject/WeakObjectPtr.h>
 
 
+class UTexture2D;
+
 // Index type to be used as a texture handle.
 using TextureIndex = int32;
 
@@ -24,8 +26,8 @@ public:
 	FTextureManager& operator=(const FTextureManager&) = delete;
 
 	// Moving transfers ownership and leaves source empty.
-	FTextureManager(FTextureManager&&) = default;
-	FTextureManager& operator=(FTextureManager&&) = default;
+	FTextureManager(FTextureManager&&) = delete;
+	FTextureManager& operator=(FTextureManager&&) = delete;
 
 	// Initialize error texture that will be used for rendering textures without registered resources. Can be called
 	// multiple time, if color needs to be changed.
@@ -39,7 +41,7 @@ public:
 	// @returns The index of a texture with given name or INDEX_NONE if there is no such texture
 	TextureIndex FindTextureIndex(const FName& Name) const
 	{
-		return TextureResources.IndexOfByPredicate([&](const auto& Entry) { return Entry.Name == Name; });
+		return TextureResources.IndexOfByPredicate([&](const auto& Entry) { return Entry.GetName() == Name; });
 	}
 
 	// Get the name of a texture at given index. Returns NAME_None, if index is out of range.
@@ -47,7 +49,7 @@ public:
 	// @returns The name of a texture at given index or NAME_None if index is out of range.
 	FName GetTextureName(TextureIndex Index) const
 	{
-		return IsInRange(Index) ? TextureResources[Index].Name : NAME_None;
+		return IsInRange(Index) ? TextureResources[Index].GetName() : NAME_None;
 	}
 
 	// Get the Slate Resource Handle to a texture at given index. If index is out of range or resources are not valid
@@ -57,10 +59,10 @@ public:
 	// found at given index
 	const FSlateResourceHandle& GetTextureHandle(TextureIndex Index) const
 	{
-		return IsValidTexture(Index) ? TextureResources[Index].ResourceHandle : ErrorTexture.ResourceHandle;
+		return IsValidTexture(Index) ? TextureResources[Index].GetResourceHandle() : ErrorTexture.GetResourceHandle();
 	}
 
-	// Create a texture from raw data. Throws exception if there is already a texture with that name.
+	// Create a texture from raw data.
 	// @param Name - The texture name
 	// @param Width - The texture width
 	// @param Height - The texture height
@@ -70,7 +72,7 @@ public:
 	// @returns The index of a texture that was created
 	TextureIndex CreateTexture(const FName& Name, int32 Width, int32 Height, uint32 SrcBpp, uint8* SrcData, TFunction<void(uint8*)> SrcDataCleanup = [](uint8*) {});
 
-	// Create a plain texture. Throws exception if there is already a texture with that name.
+	// Create a plain texture.
 	// @param Name - The texture name
 	// @param Width - The texture width
 	// @param Height - The texture height
@@ -78,16 +80,11 @@ public:
 	// @returns The index of a texture that was created
 	TextureIndex CreatePlainTexture(const FName& Name, int32 Width, int32 Height, FColor Color);
 
-	// Create Slate resources to an existing texture, managed externally. As part of an external interface it allows
-	// to loosen resource verification policy. By default (consistently with other create function) it protects from
-	// creating resources with name that is already registered. If bMakeUnique is false, then existing resources are
-	// updated/replaced. Throws exception, if name argument is NAME_None or texture is null.
+	// Create Slate resources to an existing texture, managed externally.
 	// @param Name - The texture name
 	// @param Texture - The texture
-	// @param bMakeUnique - If true (default) and there is already a texture with given name, then exception is thrown,
-	//     otherwise existing resources are updated.
 	// @returns The index to created/updated texture resources
-	TextureIndex CreateTextureResources(const FName& Name, UTexture2D* Texture, bool bMakeUnique = true);
+	TextureIndex CreateTextureResources(const FName& Name, UTexture* Texture);
 
 	// Release resources for given texture. Ignores invalid indices.
 	// @param Index - The index of a texture resources
@@ -110,7 +107,7 @@ private:
 	// @param Texture - The texture
 	// @param bAddToRoot - If true, we should add texture to root to prevent garbage collection (use for own textures)
 	// @returns The index of the entry that we created or reused
-	TextureIndex AddTextureEntry(const FName& Name, UTexture2D* Texture, bool bAddToRoot, bool bUpdate);
+	TextureIndex AddTextureEntry(const FName& Name, UTexture* Texture, bool bAddToRoot);
 
 	// Check whether index is in range allocated for TextureResources (it doesn't mean that resources are valid).
 	FORCEINLINE bool IsInRange(TextureIndex Index) const
@@ -121,14 +118,14 @@ private:
 	// Check whether index is in range and whether texture resources are valid (using NAME_None sentinel).
 	FORCEINLINE bool IsValidTexture(TextureIndex Index) const
 	{
-		return IsInRange(Index) && TextureResources[Index].Name != NAME_None;
+		return IsInRange(Index) && TextureResources[Index].GetName() != NAME_None;
 	}
 
 	// Entry for texture resources. Only supports explicit construction.
 	struct FTextureEntry
 	{
 		FTextureEntry() = default;
-		FTextureEntry(const FName& InName, UTexture2D* InTexture, bool bAddToRoot);
+		FTextureEntry(const FName& InName, UTexture* InTexture, bool bAddToRoot);
 		~FTextureEntry();
 
 		// Copying is not supported.
@@ -140,14 +137,17 @@ private:
 		// ... but we need move assignment to support reusing entries.
 		FTextureEntry& operator=(FTextureEntry&& Other);
 
-		FName Name = NAME_None;
-		TWeakObjectPtr<UTexture2D> Texture;
-		FSlateBrush Brush;
-		FSlateResourceHandle ResourceHandle;
+		const FName& GetName() const { return Name; }
+		const FSlateResourceHandle& GetResourceHandle() const;
 
 	private:
 
 		void Reset(bool bReleaseResources);
+
+		FName Name = NAME_None;
+		mutable FSlateResourceHandle CachedResourceHandle;
+		TWeakObjectPtr<UTexture> Texture;
+		FSlateBrush Brush;
 	};
 
 	TArray<FTextureEntry> TextureResources;

Source/ImGui/Private/Utilities/DebugExecBindings.cpp

@@ -1,11 +1,13 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "DebugExecBindings.h"
+
 #include "ImGuiModuleSettings.h"
 
 #include <GameFramework/PlayerInput.h>
+#include <UObject/UObjectIterator.h>
+
+#include "EnhancedPlayerInput.h"
 
 
 namespace
@@ -40,11 +42,16 @@ namespace
 
 	bool IsBindable(const FKey& Key)
 	{
+#if ENGINE_COMPATIBILITY_LEGACY_KEY_AXIS_API
 		return Key.IsValid() && Key != EKeys::AnyKey && !Key.IsFloatAxis() && !Key.IsVectorAxis()
 			&& !Key.IsGamepadKey() && !Key.IsModifierKey() && !Key.IsMouseButton();
+#else
+		return Key.IsValid() && Key != EKeys::AnyKey && !Key.IsAxis1D() && !Key.IsAxis2D()
+			&& !Key.IsAxis3D() && !Key.IsGamepadKey() && !Key.IsModifierKey() && !Key.IsMouseButton();
+#endif
 	}
 
-	void UpdatePlayerInput(UPlayerInput* PlayerInput, const FKeyBind& KeyBind)
+	void UpdatePlayerInput(UEnhancedPlayerInput* PlayerInput, const FKeyBind& KeyBind)
 	{
 		const int32 Index = PlayerInput->DebugExecBindings.IndexOfByPredicate([&](const FKeyBind& PlayerKeyBind)
 		{
@@ -81,13 +88,13 @@ namespace DebugExecBindings
 		const FKeyBind KeyBind = CreateKeyBind(KeyInfo, Command);
 
 		// Update default player input, so changes will be visible in all PIE sessions created after this point.
-		if (UPlayerInput* DefaultPlayerInput = GetMutableDefault<UPlayerInput>())
+		if (UEnhancedPlayerInput* DefaultPlayerInput = GetMutableDefault<UEnhancedPlayerInput>())
 		{
 			UpdatePlayerInput(DefaultPlayerInput, KeyBind);
 		}
 
 		// Update all existing player inputs to see changes in running PIE session.
-		for (TObjectIterator<UPlayerInput> It; It; ++It)
+		for (TObjectIterator<UEnhancedPlayerInput> It; It; ++It)
 		{
 			UpdatePlayerInput(*It, KeyBind);
 		}

Source/ImGui/Private/Utilities/DebugExecBindings.h

@@ -2,6 +2,7 @@
 
 #pragma once
 
+class FString;
 struct FImGuiKeyInfo;
 
 namespace DebugExecBindings

Source/ImGui/Private/Utilities/RedirectingHandle.h

@@ -0,0 +1,96 @@
+// Distributed under the MIT License (MIT) (see accompanying LICENSE file)
+
+#pragma once
+
+#include <Delegates/Delegate.h>
+#include <Delegates/DelegateCombinations.h>
+
+
+namespace Utilities
+{
+	// Handle initialized as a pointer to a default value, but can be redirected to follow other handles.
+	// When detached, it will revert to the default value. Intended for cross-module redirections.
+	template<typename T>
+	struct TRedirectingHandle
+	{
+		TRedirectingHandle(T& InDefaultValue)
+			: Handle(&InDefaultValue)
+			, DefaultHandle(&InDefaultValue)
+		{
+		}
+
+		~TRedirectingHandle()
+		{
+			// Broadcast null pointer as a request to detach.
+			OnRedirectionUpdate.Broadcast(nullptr);
+		}
+
+		// Check whether this handle points to the default value.
+		bool IsDefault() const
+		{
+			return (Handle == DefaultHandle);
+		}
+
+		// Get the current value.
+		T& Get() const
+		{
+			return *Handle;
+		}
+
+		// Set the other handle as a parent to this one. Passing null or itself will result with detaching from
+		// the current parent (if any) and reverting back to the default value.
+		void SetParent(TRedirectingHandle* InParent)
+		{
+			if (InParent != Parent)
+			{
+				if (Parent)
+				{
+					Parent->OnRedirectionUpdate.RemoveAll(this);
+				}
+
+				// Protecting from setting itself as a parent.
+				Parent = (InParent != this) ? InParent : nullptr;
+
+				if (Parent)
+				{
+					Parent->OnRedirectionUpdate.AddRaw(this, &TRedirectingHandle::UpdateRedirection);
+				}
+
+				SetHandle((Parent) ? Parent->Handle : DefaultHandle);
+			}
+		}
+
+	protected:
+
+		void UpdateRedirection(T* InHandle)
+		{
+			if (InHandle)
+			{
+				SetHandle(InHandle);
+			}
+			else
+			{
+				// Interpreting null as a signal to detach.
+				SetParent(nullptr);
+			}
+		}
+
+		void SetHandle(T* InHandle)
+		{
+			if (InHandle != Handle)
+			{
+				Handle = InHandle;
+				OnRedirectionUpdate.Broadcast(Handle);
+			}
+		}
+
+		T* Handle;
+		T* DefaultHandle;
+
+		TRedirectingHandle* Parent = nullptr;
+
+		// Event with a new handle value or null pointer as a signal to detach.
+		DECLARE_MULTICAST_DELEGATE_OneParam(FRedirectionUpdateDelegate, T*);
+		FRedirectionUpdateDelegate OnRedirectionUpdate;
+	};
+}

Source/ImGui/Private/Utilities/ScopeGuards.h

@@ -1,58 +0,0 @@
-// Distributed under the MIT License (MIT) (see accompanying LICENSE file)
-
-#pragma once
-
-namespace ScopeGuards
-{
-	// Saves snapshot of the object state and restores it during destruction.
-	template<typename T>
-	class TStateSaver
-	{
-	public:
-
-		// Constructor taking target object in state that we want to save.
-		TStateSaver(T& Target)
-			: Ptr(&Target)
-			, Value(Target)
-		{
-		}
-
-		// Move constructor allowing to transfer state out of scope.
-		TStateSaver(TStateSaver&& Other)
-			: Ptr(Other.Ptr)
-			, Value(MoveTemp(Other.Value))
-		{
-			// Release responsibility from the other object (std::exchange currently not supported by all platforms).
-			Other.Ptr = nullptr;
-		}
-
-		// Non-assignable to enforce acquisition on construction.
-		TStateSaver& operator=(TStateSaver&&) = delete;
-
-		// Non-copyable.
-		TStateSaver(const TStateSaver&) = delete;
-		TStateSaver& operator=(const TStateSaver&) = delete;
-
-		~TStateSaver()
-		{
-			if (Ptr)
-			{
-				*Ptr = Value;
-			}
-		}
-
-	private:
-
-		T* Ptr;
-		T Value;
-	};
-
-	// Create a state saver for target object. Unless saver is moved, state will be restored at the end of scope.
-	// @param Target - Target object in state that we want to save
-	// @returns State saver that unless moved, will restore target's state during scope exit
-	template<typename T>
-	TStateSaver<T> MakeStateSaver(T& Target)
-	{
-		return TStateSaver<T>{ Target };
-	}
-}

Source/ImGui/Private/Utilities/WorldContext.cpp

@@ -1,7 +1,5 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "WorldContext.h"
 
 

Source/ImGui/Private/Utilities/WorldContext.h

@@ -2,8 +2,10 @@
 
 #pragma once
 
-#include <Core.h>
-#include <Engine.h>
+#include <Engine/Engine.h>
+#include <Engine/GameInstance.h>
+#include <Engine/GameViewportClient.h>
+#include <UObject/WeakObjectPtr.h>
 
 
 // Utilities helping to get a World Context.

Source/ImGui/Private/Utilities/WorldContextIndex.h

@@ -6,35 +6,26 @@
 
 
 // Utilities mapping worlds to indices that we use to identify ImGui contexts.
-// Editor and standalone games have context index 0 while PIE worlds have indices starting from 1 for server and 2+ for
-// clients.
 
 namespace Utilities
 {
 	// Invalid context index for parameters that cannot be resolved to a valid world.
-	static constexpr int32 INVALID_CONTEXT_INDEX = -1;
+	static constexpr int32 INVALID_CONTEXT_INDEX = -10;
 
 	// Standalone context index.
-	static constexpr int32 STANDALONE_GAME_CONTEXT_INDEX = 0;
+	static constexpr int32 STANDALONE_GAME_CONTEXT_INDEX = -2;
 
 #if WITH_EDITOR
 
-	// Editor context index.
-	static constexpr int32 EDITOR_CONTEXT_INDEX = 0;
+	// Editor context index. We are lacking flexibility here, so we might need to change it somehow.
+	static constexpr int32 EDITOR_CONTEXT_INDEX = -1;
 
 	FORCEINLINE int32 GetWorldContextIndex(const FWorldContext& WorldContext)
 	{
-		// In standalone game (WorldType = Game) we have only one context with index 0 (see GAME_CONTEXT_INDEX).
-
-		// In editor, we keep 0 for editor and use PIEInstance to index worlds. In simulation or standalone single-PIE
-		// sessions PIEInstance is 0, but since there is only one world we can change it without causing any conflicts.
-		// In single-PIE with dedicated server or multi-PIE sessions worlds have PIEInstance starting from 1 for server
-		// and 2+ for clients, what maps directly to our index.
-
 		switch (WorldContext.WorldType)
 		{
 		case EWorldType::PIE:
-			return FMath::Max(WorldContext.PIEInstance, 1);
+			return WorldContext.PIEInstance;
 		case EWorldType::Game:
 			return STANDALONE_GAME_CONTEXT_INDEX;
 		case EWorldType::Editor:

Source/ImGui/Private/VersionCompatibility.h

@@ -9,22 +9,29 @@
 // One place to define compatibility with older engine versions.
 
 
-// Starting from version 4.17 Slate has an improved clipping API. Old version required to specify per-vertex clipping
+// Starting from version 4.17, Slate has an improved clipping API. Old version required to specify per-vertex clipping
 // rectangle and unofficial GSlateScissorRect to correctly clip custom vertices made with FSlateDrawElement.
 #define ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API        BELOW_ENGINE_VERSION(4, 17)
 
-// Starting from version 4.18 FPaths::GameSavedDir() has been superseded by FPaths::ProjectSavedDir().
+// Starting from version 4.18, FPaths::GameSavedDir() has been superseded by FPaths::ProjectSavedDir().
 #define ENGINE_COMPATIBILITY_LEGACY_SAVED_DIR           BELOW_ENGINE_VERSION(4, 18)
 
-// Starting from version 4.18 we have support for dual key bindings.
+// Starting from version 4.18, we have support for dual key bindings.
 #define ENGINE_COMPATIBILITY_SINGLE_KEY_BINDING         BELOW_ENGINE_VERSION(4, 18)
 
-// Starting from version 4.18 FStringClassReference is replaced by FSoftClassPath. The new header contains a typedef
+// Starting from version 4.18, FStringClassReference is replaced by FSoftClassPath. The new header contains a typedef
 // that renames FStringClassReference to FSoftClassPath, so it is still possible tu use the old type name in code.
 // The old header forwards to the new one but if used it outputs a warning, so we want to avoid it.
 #define ENGINE_COMPATIBILITY_LEGACY_STRING_CLASS_REF    BELOW_ENGINE_VERSION(4, 18)
 
-// Starting from version 4.18 engine has a world post actor tick event which if available, provides a good opportunity
+// Starting from version 4.18, engine has a world post actor tick event which if available, provides a good opportunity
 // to call debug delegates after world actors are already updated.
 #define ENGINE_COMPATIBILITY_WITH_WORLD_POST_ACTOR_TICK FROM_ENGINE_VERSION(4, 18)
 
+// Starting from version 4.24, world actor tick event has additional world parameter.
+#define ENGINE_COMPATIBILITY_LEGACY_WORLD_ACTOR_TICK    BELOW_ENGINE_VERSION(4, 24)
+
+// Starting from version 4.26, FKey::IsFloatAxis and FKey::IsVectorAxis are deprecated and replaced with FKey::IsAxis[1|2|3]D methods.
+#define ENGINE_COMPATIBILITY_LEGACY_KEY_AXIS_API        BELOW_ENGINE_VERSION(4, 26)
+
+#define ENGINE_COMPATIBILITY_LEGACY_VECTOR2F            BELOW_ENGINE_VERSION(5, 0)

Source/ImGui/Private/Widgets/SImGuiCanvasControl.cpp

@@ -1,9 +1,12 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "SImGuiCanvasControl.h"
 
+#include "VersionCompatibility.h"
+
+#include <Rendering/DrawElements.h>
+#include <SlateOptMacros.h>
+
 
 namespace
 {
@@ -173,7 +176,7 @@ FReply SImGuiCanvasControl::OnDragOver(const FGeometry& MyGeometry, const FDragD
 	if (Operation.IsValid())
 	{
 		const FSlateRenderTransform ScreenToWidget = MyGeometry.GetAccumulatedRenderTransform().Inverse();
-		const FVector2D DragDelta = ScreenToWidget.TransformVector(DragDropEvent.GetScreenSpacePosition() - Operation->StartPosition);
+		const FVector2D DragDelta = ScreenToWidget.TransformVector(FVector2D(DragDropEvent.GetScreenSpacePosition() - Operation->StartPosition));
 	
 		if (Operation->DragType == EDragType::Content)
 		{

Source/ImGui/Private/Widgets/SImGuiCanvasControl.h

@@ -3,9 +3,10 @@
 #pragma once
 
 #include "ImGuiInputState.h"
-#include "ImGuiModuleDebug.h"
 #include "ImGuiModuleSettings.h"
 
+#include <Brushes/SlateBorderBrush.h>
+#include <Widgets/DeclarativeSyntaxSupport.h>
 #include <Widgets/SLeafWidget.h>
 
 

Source/ImGui/Private/Widgets/SImGuiLayout.cpp

@@ -1,10 +1,12 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "SImGuiLayout.h"
 #include "SImGuiWidget.h"
 
+#include "ImGuiModuleManager.h"
+#include "ImGuiModuleSettings.h"
+
+#include <SlateOptMacros.h>
 #include <Widgets/Layout/SConstraintCanvas.h>
 #include <Widgets/Layout/SDPIScaler.h>
 #include <Widgets/Layout/SScaleBox.h>
@@ -15,9 +17,18 @@ void SImGuiLayout::Construct(const FArguments& InArgs)
 {
 	checkf(InArgs._GameViewport, TEXT("Null Game Viewport argument"));
 
+	ModuleManager = InArgs._ModuleManager;
 	GameViewport = InArgs._GameViewport;
 
-	// TODO: Remove instantiation of ImGui Widget outside of this class.
+	if (ModuleManager)
+	{
+		auto& Settings = ModuleManager->GetSettings();
+		SetDPIScale(Settings.GetDPIScaleInfo());
+		if (!Settings.OnDPIScaleChangedDelegate.IsBoundToObject(this))
+		{
+			Settings.OnDPIScaleChangedDelegate.AddRaw(this, &SImGuiLayout::SetDPIScale);
+		}
+	}
 
 	ChildSlot
 	[
@@ -26,11 +37,12 @@ void SImGuiLayout::Construct(const FArguments& InArgs)
 		.IgnoreInheritedScale(true)
 		.HAlign(HAlign_Fill)
 		.VAlign(VAlign_Fill)
+		.Visibility(EVisibility::SelfHitTestInvisible)
 		[
-			// Apply custom scale if necessary.
-			// TODO: Bind to relevant parameter.
+			// Apply custom scale if needed.
 			SNew(SDPIScaler)
-			.DPIScale(1.f)
+			.DPIScale(TAttribute<float>(this, &SImGuiLayout::GetDPIScale))
+			.Visibility(EVisibility::SelfHitTestInvisible)
 			[
 				SNew(SConstraintCanvas)
 				+ SConstraintCanvas::Slot()
@@ -51,5 +63,21 @@ void SImGuiLayout::Construct(const FArguments& InArgs)
 			]
 		]
 	];
+
+	SetVisibility(EVisibility::SelfHitTestInvisible);
 }
+
+SImGuiLayout::~SImGuiLayout()
+{
+	if (ModuleManager)
+	{
+		ModuleManager->GetSettings().OnDPIScaleChangedDelegate.RemoveAll(this);
+	}
+}
+
 END_SLATE_FUNCTION_BUILD_OPTIMIZATION
+
+void SImGuiLayout::SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo)
+{
+	DPIScale = ScaleInfo.GetSlateScale();
+}

Source/ImGui/Private/Widgets/SImGuiLayout.h

@@ -2,11 +2,14 @@
 
 #pragma once
 
+#include <UObject/WeakObjectPtr.h>
+#include <Widgets/DeclarativeSyntaxSupport.h>
 #include <Widgets/SCompoundWidget.h>
 
 
 class FImGuiModuleManager;
 class UGameViewportClient;
+struct FImGuiDPIScaleInfo;
 
 // Layout preset for ImGui Widget.
 class SImGuiLayout : public SCompoundWidget
@@ -24,9 +27,17 @@ public:
 
 	void Construct(const FArguments& InArgs);
 
+	~SImGuiLayout();
+
 	const TWeakObjectPtr<UGameViewportClient>& GetGameViewport() const { return GameViewport; }
 
 private:
 
+	float GetDPIScale() const { return DPIScale; }
+	void SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo);
+
+	FImGuiModuleManager* ModuleManager = nullptr;
 	TWeakObjectPtr<UGameViewportClient> GameViewport;
+
+	float DPIScale = 1.f;
 };

Source/ImGui/Private/Widgets/SImGuiWidget.cpp

@@ -1,13 +1,10 @@
 // Distributed under the MIT License (MIT) (see accompanying LICENSE file)
 
-#include "ImGuiPrivatePCH.h"
-
 #include "SImGuiWidget.h"
 #include "SImGuiCanvasControl.h"
 
 #include "ImGuiContextManager.h"
 #include "ImGuiContextProxy.h"
-#include "ImGuiImplementation.h"
 #include "ImGuiInputHandler.h"
 #include "ImGuiInputHandlerFactory.h"
 #include "ImGuiInteroperability.h"
@@ -15,9 +12,15 @@
 #include "ImGuiModuleSettings.h"
 #include "TextureManager.h"
 #include "Utilities/Arrays.h"
-#include "Utilities/ScopeGuards.h"
+#include "VersionCompatibility.h"
 
 #include <Engine/Console.h>
+#include <Engine/GameViewportClient.h>
+#include <Engine/LocalPlayer.h>
+#include <Framework/Application/SlateApplication.h>
+#include <GameFramework/GameUserSettings.h>
+#include <SlateOptMacros.h>
+#include <Widgets/SViewport.h>
 
 #include <utility>
 
@@ -58,6 +61,24 @@ namespace CVars
 }
 #endif // IMGUI_WIDGET_DEBUG
 
+namespace
+{
+	FORCEINLINE FVector2D MaxVector(const FVector2D& A, const FVector2D& B)
+	{
+		return FVector2D(FMath::Max(A.X, B.X), FMath::Max(A.Y, B.Y));
+	}
+
+	FORCEINLINE FVector2D RoundVector(const FVector2D& Vector)
+	{
+		return FVector2D(FMath::RoundToFloat(Vector.X), FMath::RoundToFloat(Vector.Y));
+	}
+
+	FORCEINLINE FSlateRenderTransform RoundTranslation(const FSlateRenderTransform& Transform)
+	{
+		return FSlateRenderTransform(Transform.GetMatrix(), RoundVector(Transform.GetTranslation()));
+	}
+}
+
 BEGIN_SLATE_FUNCTION_BUILD_OPTIMIZATION
 void SImGuiWidget::Construct(const FArguments& InArgs)
 {
@@ -68,33 +89,29 @@ void SImGuiWidget::Construct(const FArguments& InArgs)
 	GameViewport = InArgs._GameViewport;
 	ContextIndex = InArgs._ContextIndex;
 
-	// Disable mouse cursor over this widget as we will use ImGui to draw it.
-	SetCursor(EMouseCursor::None);
-
-	// Sync visibility with default input enabled state.
-	UpdateVisibility();
-
-	// Register to get post-update notifications, so we can clean frame updates.
+	// Register to get post-update notifications.
 	ModuleManager->OnPostImGuiUpdate().AddRaw(this, &SImGuiWidget::OnPostImGuiUpdate);
 
-	// Bind this widget to its context proxy.
+	// Register debug delegate.
 	auto* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
 	checkf(ContextProxy, TEXT("Missing context during widget construction: ContextIndex = %d"), ContextIndex);
 #if IMGUI_WIDGET_DEBUG
 	ContextProxy->OnDraw().AddRaw(this, &SImGuiWidget::OnDebugDraw);
 #endif // IMGUI_WIDGET_DEBUG
-	ContextProxy->SetInputState(&InputState);
 
 	// Register for settings change.
 	RegisterImGuiSettingsDelegates();
 
+	// Get initial settings.
 	const auto& Settings = ModuleManager->GetSettings();
-
-	// Cache locally software cursor mode.
-	SetUseSoftwareCursor(Settings.UseSoftwareCursor());
-
-	// Create ImGui Input Handler.
+	SetHideMouseCursor(Settings.UseSoftwareCursor());
 	CreateInputHandler(Settings.GetImGuiInputHandlerClass());
+	SetDPIScale(Settings.GetDPIScaleInfo());
+	SetCanvasSizeInfo(Settings.GetCanvasSizeInfo());
+
+	// Initialize state.
+	UpdateVisibility();
+	UpdateMouseCursor();
 
 	ChildSlot
 	[
@@ -119,7 +136,6 @@ SImGuiWidget::~SImGuiWidget()
 #if IMGUI_WIDGET_DEBUG
 		ContextProxy->OnDraw().RemoveAll(this);
 #endif // IMGUI_WIDGET_DEBUG
-		ContextProxy->RemoveInputState(&InputState);
 	}
 
 	// Unregister from post-update notifications.
@@ -130,154 +146,75 @@ void SImGuiWidget::Tick(const FGeometry& AllottedGeometry, const double InCurren
 {
 	Super::Tick(AllottedGeometry, InCurrentTime, InDeltaTime);
 
-	UpdateMouseStatus();
-
-	// Note: Moving that update to console variable sink or callback might seem like a better alternative but input
-	// setup in this function is better handled here.
-	UpdateInputEnabled();
-}
-
-namespace
-{
-	FReply ToSlateReply(const FImGuiInputResponse& HandlingResponse)
-	{
-		return HandlingResponse.HasConsumeRequest() ? FReply::Handled() : FReply::Unhandled();
-	}
+	UpdateInputState();
+	UpdateTransparentMouseInput(AllottedGeometry);
+	HandleWindowFocusLost();
+	UpdateCanvasSize();
 }
 
 FReply SImGuiWidget::OnKeyChar(const FGeometry& MyGeometry, const FCharacterEvent& CharacterEvent)
 {
-	const FImGuiInputResponse Response = InputHandler->OnKeyChar(CharacterEvent);
-	if (Response.HasProcessingRequest())
-	{
-		InputState.AddCharacter(CharacterEvent.GetCharacter());
-	}
-
-	return ToSlateReply(Response);
+	return InputHandler->OnKeyChar(CharacterEvent);
 }
 
 FReply SImGuiWidget::OnKeyDown(const FGeometry& MyGeometry, const FKeyEvent& KeyEvent)
 {
-	if (KeyEvent.GetKey().IsGamepadKey())
-	{
-		if (InputState.IsGamepadNavigationEnabled())
-		{
-			const FImGuiInputResponse Response = InputHandler->OnGamepadKeyDown(KeyEvent);
-			if (Response.HasProcessingRequest())
-			{
-				InputState.SetGamepadNavigationKey(KeyEvent, true);
-			}
-
-			return ToSlateReply(Response);
-		}
-		else
-		{
-			return Super::OnKeyDown(MyGeometry, KeyEvent);
-		}
-	}
-	else
-	{
-		UpdateCanvasControlMode(KeyEvent);
-
-		const FImGuiInputResponse Response = InputHandler->OnKeyDown(KeyEvent);
-		if (Response.HasProcessingRequest())
-		{
-			InputState.SetKeyDown(KeyEvent, true);
-			CopyModifierKeys(KeyEvent);
-		}
-
-		return ToSlateReply(Response);
-	}
+	UpdateCanvasControlMode(KeyEvent);
+	return InputHandler->OnKeyDown(KeyEvent);
 }
 
 FReply SImGuiWidget::OnKeyUp(const FGeometry& MyGeometry, const FKeyEvent& KeyEvent)
 {
-	if (KeyEvent.GetKey().IsGamepadKey())
-	{
-		if (InputState.IsGamepadNavigationEnabled())
-		{
-			// Always handle key up events to protect from leaving accidental keys not cleared in ImGui input state.
-			InputState.SetGamepadNavigationKey(KeyEvent, false);
-
-			return ToSlateReply(InputHandler->OnGamepadKeyUp(KeyEvent));
-		}
-		else
-		{
-			return Super::OnKeyUp(MyGeometry, KeyEvent);
-		}
-	}
-	else
-	{
-		UpdateCanvasControlMode(KeyEvent);
-
-		// Always handle key up events to protect from leaving accidental keys not cleared in ImGui input state.
-		InputState.SetKeyDown(KeyEvent, false);
-		CopyModifierKeys(KeyEvent);
-
-		return ToSlateReply(InputHandler->OnKeyUp(KeyEvent));
-	}
+	UpdateCanvasControlMode(KeyEvent);
+	return InputHandler->OnKeyUp(KeyEvent);
 }
 
 FReply SImGuiWidget::OnAnalogValueChanged(const FGeometry& MyGeometry, const FAnalogInputEvent& AnalogInputEvent)
 {
-	if (AnalogInputEvent.GetKey().IsGamepadKey() && InputState.IsGamepadNavigationEnabled())
-	{
-		const FImGuiInputResponse Response = InputHandler->OnGamepadAxis(AnalogInputEvent);
-		if (Response.HasProcessingRequest())
-		{
-			InputState.SetGamepadNavigationAxis(AnalogInputEvent, AnalogInputEvent.GetAnalogValue());
-		}
-
-		return ToSlateReply(Response);
-	}
-	else
-	{
-		return Super::OnAnalogValueChanged(MyGeometry, AnalogInputEvent);
-	}
+	return InputHandler->OnAnalogValueChanged(AnalogInputEvent);
 }
 
 FReply SImGuiWidget::OnMouseButtonDown(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
 {
-	InputState.SetMouseDown(MouseEvent, true);
-	CopyModifierKeys(MouseEvent);
-
-	return FReply::Handled();
+	return InputHandler->OnMouseButtonDown(MouseEvent).LockMouseToWidget(SharedThis(this));
 }
 
 FReply SImGuiWidget::OnMouseButtonDoubleClick(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
 {
-	InputState.SetMouseDown(MouseEvent, true);
-	CopyModifierKeys(MouseEvent);
+	return InputHandler->OnMouseButtonDoubleClick(MouseEvent).LockMouseToWidget(SharedThis(this));
+}
 
-	return FReply::Handled();
+namespace
+{
+	bool NeedMouseLock(const FPointerEvent& MouseEvent)
+	{
+#if FROM_ENGINE_VERSION(4, 20)
+		return FSlateApplication::Get().GetPressedMouseButtons().Num() > 0;
+#else
+		return MouseEvent.IsMouseButtonDown(EKeys::LeftMouseButton) || MouseEvent.IsMouseButtonDown(EKeys::MiddleMouseButton)
+			|| MouseEvent.IsMouseButtonDown(EKeys::RightMouseButton);
+#endif
+	}
 }
 
 FReply SImGuiWidget::OnMouseButtonUp(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
 {
-	InputState.SetMouseDown(MouseEvent, false);
-	CopyModifierKeys(MouseEvent);
-
-	return FReply::Handled();
+	FReply Reply = InputHandler->OnMouseButtonUp(MouseEvent);
+	if (!NeedMouseLock(MouseEvent))
+	{
+		Reply.ReleaseMouseLock();
+	}
+	return Reply;
 }
 
 FReply SImGuiWidget::OnMouseWheel(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
 {
-	InputState.AddMouseWheelDelta(MouseEvent.GetWheelDelta());
-	CopyModifierKeys(MouseEvent);
-
-	return FReply::Handled();
+	return InputHandler->OnMouseWheel(MouseEvent);
 }
 
 FReply SImGuiWidget::OnMouseMove(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
 {
-	const FSlateRenderTransform ImGuiToScreen = ImGuiTransform.Concatenate(MyGeometry.GetAccumulatedRenderTransform());
-	InputState.SetMousePosition(ImGuiToScreen.Inverse().TransformPoint(MouseEvent.GetScreenSpacePosition()));
-	CopyModifierKeys(MouseEvent);
-
-	// This event is called in every frame when we have a mouse, so we can use it to raise notifications.
-	NotifyMouseEvent();
-
-	return FReply::Handled();
+	return InputHandler->OnMouseMove(TransformScreenPointToImGui(MyGeometry, MouseEvent.GetScreenSpacePosition()), MouseEvent);
 }
 
 FReply SImGuiWidget::OnFocusReceived(const FGeometry& MyGeometry, const FFocusEvent& FocusEvent)
@@ -286,9 +223,9 @@ FReply SImGuiWidget::OnFocusReceived(const FGeometry& MyGeometry, const FFocusEv
 
 	IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Focus Received."), ContextIndex);
 
-	// If widget has a keyboard focus we always maintain mouse input. Technically, if mouse is outside of the widget
-	// area it won't generate events but we freeze its state until it either comes back or input is completely lost.
-	UpdateInputMode(true, IsDirectlyHovered());
+	bForegroundWindow = GameViewport->Viewport->IsForegroundWindow();
+	InputHandler->OnKeyboardInputEnabled();
+	InputHandler->OnGamepadInputEnabled();
 
 	FSlateApplication::Get().ResetToDefaultPointerInputSettings();
 	return FReply::Handled();
@@ -300,7 +237,8 @@ void SImGuiWidget::OnFocusLost(const FFocusEvent& FocusEvent)
 
 	IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Focus Lost."), ContextIndex);
 
-	UpdateInputMode(false, IsDirectlyHovered());
+	InputHandler->OnKeyboardInputDisabled();
+	InputHandler->OnGamepadInputDisabled();
 }
 
 void SImGuiWidget::OnMouseEnter(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
@@ -309,17 +247,7 @@ void SImGuiWidget::OnMouseEnter(const FGeometry& MyGeometry, const FPointerEvent
 
 	IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Mouse Enter."), ContextIndex);
 
-	// If mouse enters while input is active then we need to update mouse buttons because there is a chance that we
-	// missed some events.
-	if (InputMode != EInputMode::None)
-	{
-		for (const FKey& Button : { EKeys::LeftMouseButton, EKeys::MiddleMouseButton, EKeys::RightMouseButton, EKeys::ThumbMouseButton, EKeys::ThumbMouseButton2 })
-		{
-			InputState.SetMouseDown(Button, MouseEvent.IsMouseButtonDown(Button));
-		}
-	}
-
-	UpdateInputMode(HasKeyboardFocus(), true);
+	InputHandler->OnMouseInputEnabled();
 }
 
 void SImGuiWidget::OnMouseLeave(const FPointerEvent& MouseEvent)
@@ -328,26 +256,26 @@ void SImGuiWidget::OnMouseLeave(const FPointerEvent& MouseEvent)
 
 	IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Mouse Leave."), ContextIndex);
 
-	// We don't get any events when application loses focus, but often this is followed by OnMouseLeave, so we can use
-	// this event to immediately disable keyboard input if application lost focus.
-	UpdateInputMode(HasKeyboardFocus() && GameViewport->Viewport->IsForegroundWindow(), false);
+	InputHandler->OnMouseInputDisabled();
 }
 
-FCursorReply SImGuiWidget::OnCursorQuery(const FGeometry& MyGeometry, const FPointerEvent& CursorEvent) const
+FReply SImGuiWidget::OnTouchStarted(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent)
 {
-	EMouseCursor::Type MouseCursor = EMouseCursor::None;
-	if (!bUseSoftwareCursor)
-	{
-		if (FImGuiContextProxy* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex))
-		{
-			MouseCursor = ContextProxy->GetMouseCursor();
-		}
-	}
-
-	return FCursorReply::Cursor(MouseCursor);
+	return InputHandler->OnTouchStarted(TransformScreenPointToImGui(MyGeometry, TouchEvent.GetScreenSpacePosition()), TouchEvent);
 }
 
-void SImGuiWidget::CreateInputHandler(const FStringClassReference& HandlerClassReference)
+FReply SImGuiWidget::OnTouchMoved(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent)
+{
+	return InputHandler->OnTouchMoved(TransformScreenPointToImGui(MyGeometry, TouchEvent.GetScreenSpacePosition()), TouchEvent);
+}
+
+FReply SImGuiWidget::OnTouchEnded(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent)
+{
+	UpdateVisibility();
+	return InputHandler->OnTouchEnded(TransformScreenPointToImGui(MyGeometry, TouchEvent.GetScreenSpacePosition()), TouchEvent);
+}
+
+void SImGuiWidget::CreateInputHandler(const FSoftClassPath& HandlerClassReference)
 {
 	ReleaseInputHandler();
 
@@ -376,7 +304,15 @@ void SImGuiWidget::RegisterImGuiSettingsDelegates()
 	}
 	if (!Settings.OnUseSoftwareCursorChanged.IsBoundToObject(this))
 	{
-		Settings.OnUseSoftwareCursorChanged.AddRaw(this, &SImGuiWidget::SetUseSoftwareCursor);
+		Settings.OnUseSoftwareCursorChanged.AddRaw(this, &SImGuiWidget::SetHideMouseCursor);
+	}
+	if (!Settings.OnDPIScaleChangedDelegate.IsBoundToObject(this))
+	{
+		Settings.OnDPIScaleChangedDelegate.AddRaw(this, &SImGuiWidget::SetDPIScale);
+	}
+	if (!Settings.OnCanvasSizeChangedDelegate.IsBoundToObject(this))
+	{
+		Settings.OnCanvasSizeChangedDelegate.AddRaw(this, &SImGuiWidget::SetCanvasSizeInfo);
 	}
 }
 
@@ -386,20 +322,16 @@ void SImGuiWidget::UnregisterImGuiSettingsDelegates()
 
 	Settings.OnImGuiInputHandlerClassChanged.RemoveAll(this);
 	Settings.OnUseSoftwareCursorChanged.RemoveAll(this);
+	Settings.OnDPIScaleChangedDelegate.RemoveAll(this);
+	Settings.OnCanvasSizeChangedDelegate.RemoveAll(this);
 }
 
-void SImGuiWidget::CopyModifierKeys(const FInputEvent& InputEvent)
+void SImGuiWidget::SetHideMouseCursor(bool bHide)
 {
-	InputState.SetControlDown(InputEvent.IsControlDown());
-	InputState.SetShiftDown(InputEvent.IsShiftDown());
-	InputState.SetAltDown(InputEvent.IsAltDown());
-}
-
-void SImGuiWidget::CopyModifierKeys(const FPointerEvent& MouseEvent)
-{
-	if (InputMode == EInputMode::MousePointerOnly)
+	if (bHideMouseCursor != bHide)
 	{
-		CopyModifierKeys(static_cast<const FInputEvent&>(MouseEvent));
+		bHideMouseCursor = bHide;
+		UpdateMouseCursor();
 	}
 }
 
@@ -410,13 +342,27 @@ bool SImGuiWidget::IsConsoleOpened() const
 
 void SImGuiWidget::UpdateVisibility()
 {
-	// If we don't use input disable hit test to make this widget invisible for cursors hit detection.
-	SetVisibility(bInputEnabled ? EVisibility::Visible : EVisibility::HitTestInvisible);
+	// Make sure that we do not occlude other widgets, if input is disabled or if mouse is set to work in a transparent
+	// mode (hit-test invisible).
+	SetVisibility(bInputEnabled && !bTransparentMouseInput ? EVisibility::Visible : EVisibility::HitTestInvisible);
 
 	IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Visibility updated to '%s'."),
 		ContextIndex, *GetVisibility().ToString());
 }
 
+void SImGuiWidget::UpdateMouseCursor()
+{
+	if (!bHideMouseCursor)
+	{
+		const FImGuiContextProxy* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
+		SetCursor(ContextProxy ? ContextProxy->GetMouseCursor() : EMouseCursor::Default);
+	}
+	else
+	{
+		SetCursor(EMouseCursor::None);
+	}
+}
+
 ULocalPlayer* SImGuiWidget::GetLocalPlayer() const
 {
 	if (GameViewport.IsValid())
@@ -476,124 +422,206 @@ void SImGuiWidget::ReturnFocus()
 	PreviousUserFocusedWidget.Reset();
 }
 
-void SImGuiWidget::UpdateInputEnabled()
+void SImGuiWidget::UpdateInputState()
 {
-	const bool bEnabled = ModuleManager && ModuleManager->GetProperties().IsInputEnabled();
-	if (bInputEnabled != bEnabled)
-	{
-		bInputEnabled = bEnabled;
+	auto& Properties = ModuleManager->GetProperties();
+	auto* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
 
+	const bool bEnableTransparentMouseInput = Properties.IsMouseInputShared()
+#if PLATFORM_ANDROID || PLATFORM_IOS
+		&& (FSlateApplication::Get().GetCursorPos() != FVector2D::ZeroVector)
+#endif
+		&& !(ContextProxy->WantsMouseCapture() || ContextProxy->HasActiveItem());
+	if (bTransparentMouseInput != bEnableTransparentMouseInput)
+	{
+		bTransparentMouseInput = bEnableTransparentMouseInput;
+		if (bInputEnabled)
+		{
+			UpdateVisibility();
+		}
+	}
+
+	const bool bPropertiesInputEnabled = Properties.IsInputEnabled();
+	if (bInputEnabled != bPropertiesInputEnabled)
+	{
 		IMGUI_WIDGET_LOG(Log, TEXT("ImGui Widget %d - Input Enabled changed to '%s'."),
-			ContextIndex, TEXT_BOOL(bInputEnabled));
+			ContextIndex, TEXT_BOOL(bPropertiesInputEnabled));
+
+		bInputEnabled = bPropertiesInputEnabled;
 
 		UpdateVisibility();
+		UpdateMouseCursor();
 
-		if (!bInputEnabled)
+		if (bInputEnabled)
 		{
-			ReturnFocus();
-			UpdateInputMode(false, false);
-		}
-	}
+			// We won't get mouse enter, if viewport is already hovered.
+			if (GameViewport->GetGameViewportWidget()->IsHovered())
+			{
+				InputHandler->OnMouseInputEnabled();
+			}
 
-	// Note: Some widgets, like console, can reset focus to viewport after we already grabbed it. If we detect that
-	// viewport has a focus while input is enabled we will take it.
-	if (bInputEnabled && !HasKeyboardFocus() && !IsConsoleOpened())
-	{
-		const auto& ViewportWidget = GameViewport->GetGameViewportWidget();
-		if (ViewportWidget->HasKeyboardFocus() || ViewportWidget->HasFocusedDescendants())
-		{
 			TakeFocus();
 		}
+		else
+		{
+			ReturnFocus();
+		}
 	}
-
-	// We don't get any events when application loses focus (we get OnMouseLeave but not always) but we fix it with
-	// this manual check. We still allow the above code to run, even if we need to suppress keyboard input right after
-	// that.
-	if (bInputEnabled && !GameViewport->Viewport->IsForegroundWindow() && InputMode == EInputMode::Full)
+	else if(bInputEnabled)
 	{
-		UpdateInputMode(false, IsDirectlyHovered());
-	}
+		const auto& ViewportWidget = GameViewport->GetGameViewportWidget();
 
-	if (bInputEnabled)
-	{
-		InputState.SetKeyboardNavigationEnabled(ModuleManager && ModuleManager->GetProperties().IsKeyboardNavigationEnabled());
-		InputState.SetGamepadNavigationEnabled(ModuleManager && ModuleManager->GetProperties().IsGamepadNavigationEnabled());
-		const auto& Application = FSlateApplication::Get().GetPlatformApplication();
-		InputState.SetGamepad(Application.IsValid() && Application->IsGamepadAttached());
+		if (bTransparentMouseInput)
+		{
+			// If mouse is in transparent input mode and focus is lost to viewport, let viewport keep it and disable
+			// the whole input to match that state.
+			if (GameViewport->GetGameViewportWidget()->HasMouseCapture())
+			{
+				// DON'T DISABLE OUR INPUT WHEN WE LOSE FOCUS
+				//Properties.SetInputEnabled(false);
+				//UpdateInputState();
+			}
+		}
+		else
+		{
+			// Widget tends to lose keyboard focus after console is opened. With non-transparent mouse we can fix that
+			// by manually restoring it.
+			if (!HasKeyboardFocus() && !IsConsoleOpened() && (ViewportWidget->HasKeyboardFocus() || ViewportWidget->HasFocusedDescendants()))
+			{
+				TakeFocus();
+			}
+		}
 	}
 }
 
-void SImGuiWidget::UpdateInputMode(bool bHasKeyboardFocus, bool bHasMousePointer)
+void SImGuiWidget::UpdateTransparentMouseInput(const FGeometry& AllottedGeometry)
 {
-	const EInputMode NewInputMode =
-		bHasKeyboardFocus ? EInputMode::Full :
-		bHasMousePointer ? EInputMode::MousePointerOnly :
-		EInputMode::None;
-
-	if (InputMode != NewInputMode)
+	if (bInputEnabled && bTransparentMouseInput)
 	{
-		IMGUI_WIDGET_LOG(Verbose, TEXT("ImGui Widget %d - Input Mode changed from '%s' to '%s'."),
-			ContextIndex, TEXT_INPUT_MODE(InputMode), TEXT_INPUT_MODE(NewInputMode));
-
-		// We need to reset input components if we are either fully shutting down or we are downgrading from full to
-		// mouse-only input mode.
-		if (NewInputMode == EInputMode::None)
+		if (!GameViewport->GetGameViewportWidget()->HasMouseCapture())
 		{
-			InputState.ResetState();
+			InputHandler->OnMouseMove(TransformScreenPointToImGui(AllottedGeometry, FSlateApplication::Get().GetCursorPos()));
 		}
-		else if (InputMode == EInputMode::Full)
-		{
-			InputState.ResetKeyboardState();
-			InputState.ResetNavigationState();
-		}
-
-		InputMode = NewInputMode;
-
-		ClearMouseEventNotification();
 	}
-
-	InputState.SetMousePointer(bUseSoftwareCursor && bHasMousePointer);
 }
 
-void SImGuiWidget::UpdateMouseStatus()
+void SImGuiWidget::HandleWindowFocusLost()
 {
-	// Note: Mouse leave events can get lost if other viewport takes mouse capture (for instance console is opened by
-	// different viewport when this widget is hovered). With that we lose a chance to cleanup and hide ImGui pointer.
-	// We could either update ImGui pointer in every frame or like below, use mouse events to catch when mouse is lost.
-
-	if (InputMode == EInputMode::MousePointerOnly)
+	// We can use window foreground status to notify about application losing or receiving focus. In some situations
+	// we get mouse leave or enter events, but they are only sent if mouse pointer is inside of the viewport.
+	if (bInputEnabled && HasKeyboardFocus())
 	{
-		if (!HasMouseEventNotification())
+		if (bForegroundWindow != GameViewport->Viewport->IsForegroundWindow())
 		{
-			UpdateInputMode(false, IsDirectlyHovered());
+			bForegroundWindow = !bForegroundWindow;
+
+			IMGUI_WIDGET_LOG(VeryVerbose, TEXT("ImGui Widget %d - Updating input after %s foreground window status."),
+				ContextIndex, bForegroundWindow ? TEXT("getting") : TEXT("losing"));
+
+			if (bForegroundWindow)
+			{
+				InputHandler->OnKeyboardInputEnabled();
+				InputHandler->OnGamepadInputEnabled();
+			}
+			else
+			{
+				InputHandler->OnKeyboardInputDisabled();
+				InputHandler->OnGamepadInputDisabled();
+			}
+		}
+	}
+}
+
+void SImGuiWidget::SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo)
+{
+	const float Scale = ScaleInfo.GetSlateScale();
+	if (DPIScale != Scale)
+	{
+		DPIScale = Scale;
+		bUpdateCanvasSize = true;
+	}
+}
+
+void SImGuiWidget::SetCanvasSizeInfo(const FImGuiCanvasSizeInfo& CanvasSizeInfo)
+{
+	switch (CanvasSizeInfo.SizeType)
+	{
+		case EImGuiCanvasSizeType::Custom:
+			MinCanvasSize = { static_cast<float>(CanvasSizeInfo.Width), static_cast<float>(CanvasSizeInfo.Height) };
+			bAdaptiveCanvasSize = CanvasSizeInfo.bExtendToViewport;
+			bCanvasControlEnabled = true;
+			break;
+
+		case EImGuiCanvasSizeType::Desktop:
+			MinCanvasSize = (GEngine && GEngine->GameUserSettings)
+				? GEngine->GameUserSettings->GetDesktopResolution() : FVector2D::ZeroVector;
+			bAdaptiveCanvasSize = CanvasSizeInfo.bExtendToViewport;
+			bCanvasControlEnabled = true;
+			break;
+
+		case EImGuiCanvasSizeType::Viewport:
+		default:
+			MinCanvasSize = FVector2D::ZeroVector;
+			bAdaptiveCanvasSize = true;
+			bCanvasControlEnabled = false;
+	}
+
+	// We only update canvas control widget when canvas control is enabled. Make sure that we will not leave
+	// that widget active after disabling canvas control.
+	if (CanvasControlWidget.IsValid() && !bCanvasControlEnabled)
+	{
+		CanvasControlWidget->SetActive(false);
+	}
+
+	bUpdateCanvasSize = true;
+}
+
+void SImGuiWidget::UpdateCanvasSize()
+{
+	if (bUpdateCanvasSize)
+	{
+		if (auto* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex))
+		{
+			CanvasSize = MinCanvasSize;
+			if (bAdaptiveCanvasSize && GameViewport.IsValid())
+			{
+				FVector2D ViewportSize;
+				GameViewport->GetViewportSize(ViewportSize);
+				CanvasSize = MaxVector(CanvasSize, ViewportSize);
+			}
+			else
+			{
+				// No need for more updates, if we successfully processed fixed-canvas size.
+				bUpdateCanvasSize = false;
+			}
+
+			// Clamping DPI Scale to keep the canvas size from getting too big.
+			CanvasSize /= FMath::Max(DPIScale, 0.01f);
+			CanvasSize = RoundVector(CanvasSize);
+
+			ContextProxy->SetDisplaySize(CanvasSize);
 		}
-		ClearMouseEventNotification();
 	}
 }
 
 void SImGuiWidget::UpdateCanvasControlMode(const FInputEvent& InputEvent)
 {
-	CanvasControlWidget->SetActive(InputEvent.IsLeftAltDown() && InputEvent.IsLeftShiftDown());
+	if (bCanvasControlEnabled)
+	{
+		CanvasControlWidget->SetActive(InputEvent.IsLeftAltDown() && InputEvent.IsLeftShiftDown());
+	}
 }
 
 void SImGuiWidget::OnPostImGuiUpdate()
 {
-	if (InputMode != EInputMode::None)
-	{
-		InputState.ClearUpdateState();
-	}
-
 	ImGuiRenderTransform = ImGuiTransform;
+	UpdateMouseCursor();
 }
 
-namespace
+FVector2D SImGuiWidget::TransformScreenPointToImGui(const FGeometry& MyGeometry, const FVector2D& Point) const
 {
-	FORCEINLINE FSlateRenderTransform RoundTranslation(const FSlateRenderTransform& Transform)
-	{
-		const FVector2D& Translation = Transform.GetTranslation();
-		return FSlateRenderTransform{ Transform.GetMatrix(),
-			FVector2D{ FMath::RoundToFloat(Translation.X), FMath::RoundToFloat(Translation.Y) } };
-	}
+	const FSlateRenderTransform ImGuiToScreen = ImGuiTransform.Concatenate(MyGeometry.GetAccumulatedRenderTransform());
+	return ImGuiToScreen.Inverse().TransformPoint(Point);
 }
 
 int32 SImGuiWidget::OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeometry, const FSlateRect& MyClippingRect,
@@ -619,10 +647,6 @@ int32 SImGuiWidget::OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeo
 		{
 #if ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API
 			DrawList.CopyVertexData(VertexBuffer, ImGuiToScreen, VertexClippingRect);
-
-			// Get access to the Slate scissor rectangle defined in Slate Core API, so we can customize elements drawing.
-			extern SLATECORE_API TOptional<FShortRect> GSlateScissorRect;
-			auto GSlateScissorRectSaver = ScopeGuards::MakeStateSaver(GSlateScissorRect);
 #else
 			DrawList.CopyVertexData(VertexBuffer, ImGuiToScreen);
 #endif // ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API
@@ -644,7 +668,9 @@ int32 SImGuiWidget::OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeo
 				const FSlateRect ClippingRect = DrawCommand.ClippingRect.IntersectionWith(MyClippingRect);
 
 #if ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API
-				GSlateScissorRect = FShortRect{ ClippingRect };
+				// Get access to the Slate scissor rectangle defined in Slate Core API, so we can customize elements drawing.
+				extern SLATECORE_API TOptional<FShortRect> GSlateScissorRect;
+				TGuardValue<TOptional<FShortRect>> GSlateScissorRecGuard(GSlateScissorRect, FShortRect{ ClippingRect });
 #else
 				OutDrawElements.PushClip(FSlateClippingZone{ ClippingRect });
 #endif // ENGINE_COMPATIBILITY_LEGACY_CLIPPING_API
@@ -664,7 +690,7 @@ int32 SImGuiWidget::OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeo
 
 FVector2D SImGuiWidget::ComputeDesiredSize(float Scale) const
 {
-	return FVector2D{ 3840.f, 2160.f } * Scale;
+	return CanvasSize * Scale;
 }
 
 #if IMGUI_WIDGET_DEBUG
@@ -708,6 +734,25 @@ static TArray<FKey> GetImGuiMappedKeys()
 	return Keys;
 }
 
+namespace
+{
+	void Text(const char* Str)
+	{
+		ImGui::Text("%s:", Str);
+	}
+
+	void Text(const wchar_t* Str)
+	{
+		ImGui::Text("%ls:", Str);
+	}
+
+	template<typename CharType = std::enable_if_t<!std::is_same<TCHAR, char>::value && !std::is_same<TCHAR, wchar_t>::value, TCHAR>>
+	void Text(const CharType* Str)
+	{
+		ImGui::Text("%ls", TCHAR_TO_WCHAR(Str));
+	}
+}
+
 // Column layout utilities.
 namespace Columns
 {
@@ -733,52 +778,46 @@ namespace TwoColumns
 		Columns::CollapsingGroup(Name, 2, std::forward<FunctorType>(DrawContent));
 	}
 
-	namespace
-	{
-		void LabelText(const char* Label)
-		{
-			ImGui::Text("%s:", Label);
-		}
-
-		void LabelText(const wchar_t* Label)
-		{
-			ImGui::Text("%ls:", Label);
-		}
-	}
-
 	template<typename LabelType>
 	static void Value(LabelType&& Label, int32 Value)
 	{
-		LabelText(Label); ImGui::NextColumn();
+		Text(Label); ImGui::NextColumn();
 		ImGui::Text("%d", Value); ImGui::NextColumn();
 	}
 
 	template<typename LabelType>
 	static void Value(LabelType&& Label, uint32 Value)
 	{
-		LabelText(Label); ImGui::NextColumn();
+		Text(Label); ImGui::NextColumn();
 		ImGui::Text("%u", Value); ImGui::NextColumn();
 	}
 
 	template<typename LabelType>
 	static void Value(LabelType&& Label, float Value)
 	{
-		LabelText(Label); ImGui::NextColumn();
+		Text(Label); ImGui::NextColumn();
 		ImGui::Text("%f", Value); ImGui::NextColumn();
 	}
 
 	template<typename LabelType>
 	static void Value(LabelType&& Label, bool bValue)
 	{
-		LabelText(Label); ImGui::NextColumn();
-		ImGui::Text("%ls", TEXT_BOOL(bValue)); ImGui::NextColumn();
+		Text(Label); ImGui::NextColumn();
+		Text(TEXT_BOOL(bValue)); ImGui::NextColumn();
 	}
 
 	template<typename LabelType>
 	static void Value(LabelType&& Label, const TCHAR* Value)
 	{
-		LabelText(Label); ImGui::NextColumn();
-		ImGui::Text("%ls", Value); ImGui::NextColumn();
+		Text(Label); ImGui::NextColumn();
+		Text(Value); ImGui::NextColumn();
+	}
+
+	template<typename LabelType>
+	static void ValueWidthHeight(LabelType&& Label, const FVector2D& Value)
+	{
+		Text(Label); ImGui::NextColumn();
+		ImGui::Text("Width = %.0f, Height = %.0f", Value.X, Value.Y); ImGui::NextColumn();
 	}
 }
 
@@ -801,10 +840,12 @@ namespace Styles
 
 void SImGuiWidget::OnDebugDraw()
 {
+	FImGuiContextProxy* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
+
 	if (CVars::DebugWidget.GetValueOnGameThread() > 0)
 	{
 		bool bDebug = true;
-		ImGui::SetNextWindowSize(ImVec2(380, 480), ImGuiSetCond_Once);
+		ImGui::SetNextWindowSize(ImVec2(380, 480), ImGuiCond_Once);
 		if (ImGui::Begin("ImGui Widget Debug", &bDebug))
 		{
 			ImGui::Spacing();
@@ -812,16 +853,27 @@ void SImGuiWidget::OnDebugDraw()
 			TwoColumns::CollapsingGroup("Context", [&]()
 			{
 				TwoColumns::Value("Context Index", ContextIndex);
-				FImGuiContextProxy* ContextProxy = ModuleManager->GetContextManager().GetContextProxy(ContextIndex);
 				TwoColumns::Value("Context Name", ContextProxy ? *ContextProxy->GetName() : TEXT("< Null >"));
 				TwoColumns::Value("Game Viewport", *GameViewport->GetName());
 			});
 
+			TwoColumns::CollapsingGroup("Canvas Size", [&]()
+			{
+				TwoColumns::Value("Is Adaptive", bAdaptiveCanvasSize);
+				TwoColumns::Value("Is Updating", bUpdateCanvasSize);
+				TwoColumns::ValueWidthHeight("Min Canvas Size", MinCanvasSize);
+				TwoColumns::ValueWidthHeight("Canvas Size", CanvasSize);
+			});
+
+			TwoColumns::CollapsingGroup("DPI Scale", [&]()
+			{
+				TwoColumns::Value("Slate Scale", DPIScale);
+				TwoColumns::Value("ImGui Scale", ContextProxy ? ContextProxy->GetDPIScale() : 1.f);
+			});
+
 			TwoColumns::CollapsingGroup("Input Mode", [&]()
 			{
 				TwoColumns::Value("Input Enabled", bInputEnabled);
-				TwoColumns::Value("Input Mode", TEXT_INPUT_MODE(InputMode));
-				TwoColumns::Value("Input Has Mouse Pointer", InputState.HasMousePointer());
 			});
 
 			TwoColumns::CollapsingGroup("Widget", [&]()
@@ -853,10 +905,12 @@ void SImGuiWidget::OnDebugDraw()
 		}
 	}
 
-	if (CVars::DebugInput.GetValueOnGameThread() > 0)
+	if (ContextProxy && CVars::DebugInput.GetValueOnGameThread() > 0)
 	{
+		FImGuiInputState& InputState = ContextProxy->GetInputState();
+
 		bool bDebug = true;
-		ImGui::SetNextWindowSize(ImVec2(460, 480), ImGuiSetCond_Once);
+		ImGui::SetNextWindowSize(ImVec2(460, 480), ImGuiCond_Once);
 		if (ImGui::Begin("ImGui Input State", &bDebug))
 		{
 			const ImVec4 HiglightColor{ 1.f, 1.f, 0.5f, 1.f };

Source/ImGui/Private/Widgets/SImGuiWidget.h

@@ -2,10 +2,12 @@
 
 #pragma once
 
-#include "ImGuiInputState.h"
 #include "ImGuiModuleDebug.h"
 #include "ImGuiModuleSettings.h"
 
+#include <Rendering/RenderingCommon.h>
+#include <UObject/WeakObjectPtr.h>
+#include <Widgets/DeclarativeSyntaxSupport.h>
 #include <Widgets/SCompoundWidget.h>
 
 
@@ -16,6 +18,9 @@ class FImGuiModuleManager;
 class SImGuiCanvasControl;
 class UImGuiInputHandler;
 
+class UGameViewportClient;
+class ULocalPlayer;
+
 // Slate widget for rendering ImGui output and storing Slate inputs.
 class SImGuiWidget : public SCompoundWidget
 {
@@ -37,9 +42,6 @@ public:
 	// Get index of the context that this widget is targeting.
 	int32 GetContextIndex() const { return ContextIndex; }
 
-	// Get input state associated with this widget.
-	const FImGuiInputState& GetInputState() const { return InputState; }
-
 	//----------------------------------------------------------------------------------------------------
 	// SWidget overrides
 	//----------------------------------------------------------------------------------------------------
@@ -74,55 +76,50 @@ public:
 
 	virtual void OnMouseLeave(const FPointerEvent& MouseEvent) override;
 
-	virtual FCursorReply OnCursorQuery(const FGeometry& MyGeometry, const FPointerEvent& CursorEvent) const override;
+	virtual FReply OnTouchStarted(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent) override;
+
+	virtual FReply OnTouchMoved(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent) override;
+
+	virtual FReply OnTouchEnded(const FGeometry& MyGeometry, const FPointerEvent& TouchEvent) override;
 
 private:
 
-	enum class EInputMode : uint8
-	{
-		None,
-		// Mouse pointer only without user focus
-		MousePointerOnly,
-		// Full input with user focus (mouse, keyboard and depending on navigation mode gamepad)
-		Full
-	};
-
-	void CreateInputHandler(const FStringClassReference& HandlerClassReference);
+	void CreateInputHandler(const FSoftClassPath& HandlerClassReference);
 	void ReleaseInputHandler();
 
-	void SetUseSoftwareCursor(bool bUse) { bUseSoftwareCursor = bUse; }
-
 	void RegisterImGuiSettingsDelegates();
 	void UnregisterImGuiSettingsDelegates();
 
-	FORCEINLINE void CopyModifierKeys(const FInputEvent& InputEvent);
-	FORCEINLINE void CopyModifierKeys(const FPointerEvent& MouseEvent);
+	void SetHideMouseCursor(bool bHide);
 
 	bool IsConsoleOpened() const;
 
-	// Update visibility based on input enabled state.
+	// Update visibility based on input state.
 	void UpdateVisibility();
 
+	// Update cursor based on input state.
+	void UpdateMouseCursor();
+
 	ULocalPlayer* GetLocalPlayer() const;
 	void TakeFocus();
 	void ReturnFocus();
 
-	// Update input enabled state from console variable.
-	void UpdateInputEnabled();
+	// Update input state.
+	void UpdateInputState();
+	void UpdateTransparentMouseInput(const FGeometry& AllottedGeometry);
+	void HandleWindowFocusLost();
 
-	// Determine new input mode based on hints.
-	void UpdateInputMode(bool bHasKeyboardFocus, bool bHasMousePointer);
+	void SetDPIScale(const FImGuiDPIScaleInfo& ScaleInfo);
 
-	void UpdateMouseStatus();
-
-	FORCEINLINE bool HasMouseEventNotification() const { return bReceivedMouseEvent; }
-	FORCEINLINE void NotifyMouseEvent() { bReceivedMouseEvent = true; }
-	FORCEINLINE void ClearMouseEventNotification() { bReceivedMouseEvent = false; }
+	void SetCanvasSizeInfo(const FImGuiCanvasSizeInfo& CanvasSizeInfo);
+	void UpdateCanvasSize();
 
 	void UpdateCanvasControlMode(const FInputEvent& InputEvent);
 
 	void OnPostImGuiUpdate();
 
+	FVector2D TransformScreenPointToImGui(const FGeometry& MyGeometry, const FVector2D& Point) const;
+
 	virtual int32 OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeometry, const FSlateRect& MyClippingRect, FSlateWindowElementList& OutDrawElements, int32 LayerId, const FWidgetStyle& WidgetStyle, bool bParentEnabled) const override;
 
 	virtual FVector2D ComputeDesiredSize(float) const override;
@@ -145,14 +142,18 @@ private:
 
 	int32 ContextIndex = 0;
 
-	FImGuiInputState InputState;
+	FVector2D MinCanvasSize = FVector2D::ZeroVector;
+	FVector2D CanvasSize = FVector2D::ZeroVector;
+
+	float DPIScale = 1.f;
 
-	EInputMode InputMode = EInputMode::None;
 	bool bInputEnabled = false;
-	bool bReceivedMouseEvent = false;
-
-	// Whether or not ImGui should draw its own cursor.
-	bool bUseSoftwareCursor = false;
+	bool bForegroundWindow = false;
+	bool bHideMouseCursor = true;
+	bool bTransparentMouseInput = false;
+	bool bAdaptiveCanvasSize = false;
+	bool bUpdateCanvasSize = false;
+	bool bCanvasControlEnabled = false;
 
 	TSharedPtr<SImGuiCanvasControl> CanvasControlWidget;
 	TWeakPtr<SWidget> PreviousUserFocusedWidget;

Source/ImGui/Public/ImGuiDelegates.h

@@ -2,9 +2,11 @@
 
 #pragma once
 
-#include <Core.h>
+#include <Delegates/Delegate.h>
 
 
+class UWorld;
+
 /**
  * Delegates to ImGui debug events. World delegates are called once per frame during world updates and have invocation
  * lists cleared after their worlds become invalid. Multi-context delegates are called once for every updated world.

Source/ImGui/Public/ImGuiInputHandler.h

@@ -3,6 +3,7 @@
 #pragma once
 
 #include <CoreMinimal.h>
+#include <Input/Reply.h>
 #include <UObject/Object.h>
 #include <UObject/WeakObjectPtr.h>
 
@@ -21,77 +22,9 @@ class FUICommandInfo;
 #endif // WITH_EDITOR
 
 
-/** Response used by ImGui Input Handler to communicate input handling requests. */
-struct IMGUI_API FImGuiInputResponse
-{
-	/** Create empty response with no requests. */
-	FImGuiInputResponse() = default;
-
-	/**
-	 * Create response with custom request configuration.
-	 *
-	 * @param bInProcess - State of the processing request.
-	 * @param bInConsume - State of the consume request.
-	 */
-	FImGuiInputResponse(bool bInProcess, bool bInConsume)
-		: bProcess(bInProcess)
-		, bConsume(bInConsume)
-	{}
-
-	/**
-	 * Check whether this response contains processing request.
-	 *
-	 * @returns True, if processing was requested and false otherwise.
-	 */
-	FORCEINLINE bool HasProcessingRequest() const { return bProcess; }
-
-	/**
-	 * Check whether this response contains consume request.
-	 *
-	 * @returns True, if consume was requested and false otherwise.
-	 */
-	FORCEINLINE bool HasConsumeRequest() const { return bConsume; }
-
-	/**
-	 * Set the processing request.
-	 *
-	 * @param bInProcess - True, to request input processing (implicit) and false otherwise.
-	 * @returns Reference to this response (for chaining requests).
-	 */
-	FORCEINLINE FImGuiInputResponse& RequestProcessing(bool bInProcess = true) { bProcess = bInProcess; return *this; }
-
-	/**
-	 * Set the consume request.
-	 *
-	 * @param bInConsume - True, to request input consume (implicit) and false otherwise.
-	 * @returns Reference to this response (for chaining requests).
-	 */
-	FORCEINLINE FImGuiInputResponse& RequestConsume(bool bInConsume = true) { bConsume = bInConsume; return *this; }
-
-private:
-
-	bool bProcess = false;
-
-	bool bConsume = false;
-};
-
 /**
- * Defines behaviour when handling input events. It allows to customize handling of the keyboard and gamepad input,
- * primarily to support shortcuts in ImGui input mode. Since mouse is not really needed for this functionality and
- * mouse pointer state and focus are closely connected to input mode, mouse events are left out of this interface.
- *
- * When receiving keyboard and gamepad events ImGui Widget calls input handler to query expected behaviour. By default,
- * with a few exceptions (see @ OnKeyDown) all events are expected to be processed and consumed. Custom implementations
- * may tweak that behaviour and/or inject custom code.
- *
- * Note that returned response is only treated as a hint. In current implementation all consume requests are respected
- * but to protect from locking ImGui input states, key up events are always processed. Decision about blocking certain
- * inputs can be taken during key down events and processing corresponding key up events should not make difference.
- *
- * Also note that input handler functions are only called when ImGui Widget is receiving input events, what can be for
- * instance suppressed by opening console.
- *
- * See @ Project Settings/Plugins/ImGui/Extensions/ImGuiInputHandlerClass property to set custom implementation.
+ * Handles input and sends it to the input state, which is copied to the ImGui IO at the beginning of the frame.
+ * Implementation of the input handler can be changed in the ImGui project settings by changing ImGuiInputHandlerClass.
  */
 UCLASS()
 class IMGUI_API UImGuiInputHandler : public UObject
@@ -101,77 +34,111 @@ class IMGUI_API UImGuiInputHandler : public UObject
 public:
 
 	/**
-	 * Called when handling character events.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to process
-	 * and consume this event.
+	 * Called to handle character events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnKeyChar(const struct FCharacterEvent& CharacterEvent) { return GetDefaultKeyboardResponse(); }
+	virtual FReply OnKeyChar(const struct FCharacterEvent& CharacterEvent);
 
 	/**
-	 * Called when handling keyboard key down events.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to process
-	 * and consume most of the key, but unlike other cases it requests to ignore certain events, like those that are
-	 * needed to open console or close PIE session in editor.
+	 * Called to handle key down events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnKeyDown(const FKeyEvent& KeyEvent);
+	virtual FReply OnKeyDown(const FKeyEvent& KeyEvent);
 
 	/**
-	 * Called when handling keyboard key up events.
-	 *
-	 * Note that regardless of returned response, key up events are always processed by ImGui Widget.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to consume
-	 * this event.
+	 * Called to handle key up events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnKeyUp(const FKeyEvent& KeyEvent) { return GetDefaultKeyboardResponse(); }
+	virtual FReply OnKeyUp(const FKeyEvent& KeyEvent);
 
 	/**
-	 * Called when handling gamepad key down events.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to process
-	 * and consume this event.
+	 * Called to handle analog value change events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnGamepadKeyDown(const FKeyEvent& GamepadKeyEvent) { return GetDefaultGamepadResponse(); }
+	virtual FReply OnAnalogValueChanged(const FAnalogInputEvent& AnalogInputEvent);
 
 	/**
-	 * Called when handling gamepad key up events.
-	 *
-	 * Note that regardless of returned response, key up events are always processed by ImGui Widget.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to consume
-	 * this event.
+	 * Called to handle mouse button down events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnGamepadKeyUp(const FKeyEvent& GamepadKeyEvent) { return GetDefaultGamepadResponse(); }
+	virtual FReply OnMouseButtonDown(const FPointerEvent& MouseEvent);
 
 	/**
-	 * Called when handling gamepad analog events.
-	 *
-	 * @returns Response with rules how input should be handled. Default implementation contains requests to process
-	 * and consume this event.
+	 * Called to handle mouse button double-click events.
+	 * @returns Response whether the event was handled
 	 */
-	virtual FImGuiInputResponse OnGamepadAxis(const FAnalogInputEvent& GamepadAxisEvent) { return GetDefaultGamepadResponse(); }
+	virtual FReply OnMouseButtonDoubleClick(const FPointerEvent& MouseEvent);
+
+	/**
+	 * Called to handle mouse button up events.
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnMouseButtonUp(const FPointerEvent& MouseEvent);
+
+	/**
+	 * Called to handle mouse wheel events.
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnMouseWheel(const FPointerEvent& MouseEvent);
+
+	/**
+	 * Called to handle mouse move events.
+	 * @param MousePosition Mouse position (in ImGui space)
+	 * @param MouseEvent Optional mouse event passed from Slate
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnMouseMove(const FVector2D& MousePosition, const FPointerEvent& MouseEvent);
+	virtual FReply OnMouseMove(const FVector2D& MousePosition);
+
+	/**
+	 * Called to handle touch started event.
+	 * @param TouchPosition Touch position (in ImGui space)
+	 * @param TouchEvent Touch event passed from Slate
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnTouchStarted(const FVector2D& TouchPosition, const FPointerEvent& TouchEvent);
+
+	/**
+	 * Called to handle touch moved event.
+	 * @param TouchPosition Touch position (in ImGui space)
+	 * @param TouchEvent Touch event passed from Slate
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnTouchMoved(const FVector2D& TouchPosition, const FPointerEvent& TouchEvent);
+
+	/**
+	 * Called to handle touch ended event.
+	 * @param TouchPosition Touch position (in ImGui space)
+	 * @param TouchEvent Touch event passed from Slate
+	 * @returns Response whether the event was handled
+	 */
+	virtual FReply OnTouchEnded(const FVector2D& TouchPosition, const FPointerEvent& TouchEvent);
+
+	/** Called to handle activation of the keyboard input. */
+	virtual void OnKeyboardInputEnabled();
+
+	/** Called to handle deactivation of the keyboard input. */
+	virtual void OnKeyboardInputDisabled();
+
+	/** Called to handle activation of the gamepad input. */
+	virtual void OnGamepadInputEnabled();
+
+	/** Called to handle deactivation of the gamepad input. */
+	virtual void OnGamepadInputDisabled();
+
+	/** Called to handle activation of the mouse input. */
+	virtual void OnMouseInputEnabled();
+
+	/** Called to handle deactivation of the mouse input. */
+	virtual void OnMouseInputDisabled();
 
 protected:
 
-	/**
-	 * Get default keyboard response, with consume request based on IsKeyboardInputShared property.
-	 *
-	 * @returns Default response for keyboard inputs.
-	 */
-	FImGuiInputResponse GetDefaultKeyboardResponse() const;
-
-	/**
-	 * Get default gamepad response, with consume request based on IsGamepadInputShared property.
-	 *
-	 * @returns Default response for gamepad inputs.
-	 */
-	FImGuiInputResponse GetDefaultGamepadResponse() const;
+	/** Copy state of modifier keys to input state. */
+	void CopyModifierKeys(const FInputEvent& InputEvent);
 
 	/**
 	 * Checks whether this is a key event that can open console.
-	 *
 	 * @param KeyEvent - Key event to test.
 	 * @returns True, if this key event can open console.
 	 */
@@ -180,7 +147,6 @@ protected:
 #if WITH_EDITOR
 	/**
 	 * Checks whether this is a key event that can stop PIE session.
-	 *
 	 * @param KeyEvent - Key event to test.
 	 * @returns True, if this key event can stop PIE session.
 	 */
@@ -189,7 +155,6 @@ protected:
 
 	/**
 	 * Checks whether this key event can toggle ImGui input (as defined in settings).
-	 *
 	 * @param KeyEvent - Key event to test.
 	 * @returns True, if this key is bound to 'ImGui.ToggleInput' command that switches ImGui input mode.
 	 */
@@ -197,15 +162,28 @@ protected:
 
 	/**
 	 * Checks whether corresponding ImGui context has an active item (holding cursor focus).
-	 *
 	 * @returns True, if corresponding context has an active item.
 	 */
 	bool HasImGuiActiveItem() const;
 
 private:
 
+	void UpdateInputStatePointer();
+
+	void OnSoftwareCursorChanged(bool);
+
+	void OnPostImGuiUpdate();
+
 	void Initialize(FImGuiModuleManager* InModuleManager, UGameViewportClient* InGameViewport, int32 InContextIndex);
 
+	virtual void BeginDestroy() override;
+
+	class FImGuiInputState* InputState = nullptr;
+
+	bool bMouseInputEnabled = false;
+	bool bKeyboardInputEnabled = false;
+	bool bGamepadInputEnabled = false;
+
 	FImGuiModuleManager* ModuleManager = nullptr;
 
 	TWeakObjectPtr<UGameViewportClient> GameViewport;

Source/ImGui/Public/ImGuiModule.h

@@ -6,7 +6,7 @@
 #include "ImGuiModuleProperties.h"
 #include "ImGuiTextureHandle.h"
 
-#include <ModuleManager.h>
+#include <Modules/ModuleManager.h>
 
 
 class FImGuiModule : public IModuleInterface
@@ -57,6 +57,16 @@ public:
 	 */
 	virtual FImGuiDelegateHandle AddWorldImGuiDelegate(const FImGuiDelegate& Delegate);
 
+	/**
+	 * Add a delegate called at the end of a specific world's debug frame to draw debug controls in its ImGui context,
+	 * creating that context on demand.
+	 *
+	 * @param World - A specific world to add the delegate to to
+	 * @param Delegate - Delegate that we want to add (@see FImGuiDelegate::Create...)
+	 * @returns Returns handle that can be used to remove delegate (@see RemoveImGuiDelegate)
+	 */
+	virtual FImGuiDelegateHandle AddWorldImGuiDelegate(const UWorld* World, const FImGuiDelegate& Delegate);
+
 	/**
 	 * Add shared delegate called for each ImGui context at the end of debug frame, after calling context specific
 	 * delegate. This delegate will be used for any ImGui context, created before or after it is registered.
@@ -98,7 +108,7 @@ public:
 	 * @returns Handle to the texture resources, which can be used to release allocated resources and as an argument to
 	 *     relevant ImGui functions
 	 */
-	virtual FImGuiTextureHandle RegisterTexture(const FName& Name, class UTexture2D* Texture, bool bMakeUnique = false);
+	virtual FImGuiTextureHandle RegisterTexture(const FName& Name, class UTexture* Texture, bool bMakeUnique = false);
 
 	/**
 	 * Unregister texture and release its Slate resources. If handle is null or not valid, this function fails silently
@@ -108,6 +118,8 @@ public:
 	 */
 	virtual void ReleaseTexture(const FImGuiTextureHandle& Handle);
 
+	virtual void RebuildFontAtlas();
+
 	/**
 	 * Get ImGui module properties.
 	 *
@@ -164,11 +176,12 @@ public:
 	virtual void StartupModule() override;
 	virtual void ShutdownModule() override;
 
-	private:
-
+private:
 #if WITH_EDITOR
 	virtual void SetProperties(const FImGuiModuleProperties& Properties);
-	virtual struct ImGuiContext** GetImGuiContextHandle();
-	virtual struct FImGuiDelegatesContainer& GetDelegatesContainer();
+	struct FImGuiContextHandle* ImGuiContextHandle = nullptr;
+	struct FImGuiDelegatesContainerHandle* DelegatesContainerHandle = nullptr;
+	friend struct FImGuiContextHandle;
+	friend struct FImGuiDelegatesContainerHandle;
 #endif
 };

Source/ImGui/Public/ImGuiModuleProperties.h

@@ -2,6 +2,7 @@
 
 #pragma once
 
+struct ImFontConfig;
 
 /** Properties that define state of the ImGui module. */
 class IMGUI_API FImGuiModuleProperties
@@ -53,6 +54,15 @@ public:
 	/** Toggle whether gamepad input should be shared with game. */
 	void ToggleGamepadInputSharing() { SetGamepadInputShared(!IsGamepadInputShared()); }
 
+	/** Check whether mouse input is shared with game. */
+	bool IsMouseInputShared() const { return bMouseInputShared; }
+
+	/** Set whether mouse input should be shared with game. */
+	void SetMouseInputShared(bool bShared) { bMouseInputShared = bShared; }
+
+	/** Toggle whether mouse input should be shared with game. */
+	void ToggleMouseInputSharing() { SetMouseInputShared(!IsMouseInputShared()); }
+
 	/** Check whether ImGui demo is visible. */
 	bool ShowDemo() const { return bShowDemo; }
 
@@ -62,6 +72,24 @@ public:
 	/** Toggle ImGui demo. */
 	void ToggleDemo() { SetShowDemo(!ShowDemo()); }
 
+	/** Check whether docking is enabled. */
+	bool IsDockingEnabled() const { return bIsDockingEnabled; }
+
+	/** Set whether docking is enabled. */
+	void SetDockingEnabled(bool bDockingEnabled) { bIsDockingEnabled = bDockingEnabled; }
+
+	/** Toggle whether docking is enabled. */
+	void ToggleDockingEnabled() { SetDockingEnabled(!IsDockingEnabled()); }
+	
+	/** Adds a new font to initialize */
+	void AddCustomFont(FName FontName, TSharedPtr<ImFontConfig> Font) { CustomFonts.Emplace(FontName, Font); }
+
+	/** Removes a font from the custom font list */
+	void RemoveCustomFont(FName FontName) { CustomFonts.Remove(FontName); }
+
+	/** Gets the map of registered custom fonts */
+	TMap<FName, TSharedPtr<ImFontConfig>>& GetCustomFonts() { return CustomFonts; }
+
 private:
 
 	bool bInputEnabled = false;
@@ -71,6 +99,11 @@ private:
 
 	bool bKeyboardInputShared = false;
 	bool bGamepadInputShared = false;
+	bool bMouseInputShared = false;
 
 	bool bShowDemo = false;
+
+	bool bIsDockingEnabled = true;
+	
+	TMap<FName, TSharedPtr<ImFontConfig>> CustomFonts;
 };

Source/ThirdParty/ImGuiLibrary/Docs/BACKENDS.md

@@ -0,0 +1,146 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Backends
+
+### Integrating backends
+
+💡 The **[Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) wiki guide** has examples of how to integrate Dear ImGui into an existing application.
+<BR> The [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) documentation may also be worth a read.
+
+### What are backends?
+
+Dear ImGui is highly portable and only requires a few things to run and render, typically:
+
+ - Required: providing mouse/keyboard inputs (fed into the `ImGuiIO` structure).
+ - Required: uploading the font atlas texture into graphics memory.
+ - Required: rendering indexed textured triangles with a clipping rectangle.
+
+ Extra features are opt-in, our backends try to support as many as possible:
+
+ - Optional: custom texture binding support.
+ - Optional: clipboard support.
+ - Optional: gamepad support.
+ - Optional: mouse cursor shape support.
+ - Optional: IME support.
+ - Optional: multi-viewports support.
+ etc.
+
+This is essentially what each backend is doing + obligatory portability cruft. Using standard backends ensure you can get all those features including the ones that would be harder to implement on your side (e.g. multi-viewports support).
+
+It is important to understand the difference between the core Dear ImGui library (files in the root folder)
+and the backends which we are describing here (backends/ folder).
+
+- Some issues may only be backend or platform specific.
+- You should be able to write backends for pretty much any platform and any 3D graphics API.
+  e.g. you can get creative and use software rendering or render remotely on a different machine.
+
+### Standard backends
+
+**The [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder contains backends for popular platforms/graphics API, which you can use in
+your application or engine to easily integrate Dear ImGui.** Each backend is typically self-contained in a pair of files: imgui_impl_XXXX.cpp + imgui_impl_XXXX.h.
+
+- The 'Platform' backends are in charge of: mouse/keyboard/gamepad inputs, cursor shape, timing, and windowing.<BR>
+  e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), SDL2 ([imgui_impl_sdl2.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl2.cpp)), etc.
+
+- The 'Renderer' backends are in charge of: creating atlas texture, and rendering imgui draw data.<BR>
+  e.g. DirectX11 ([imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)), OpenGL/WebGL ([imgui_impl_opengl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_opengl3.cpp)), Vulkan ([imgui_impl_vulkan.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_vulkan.cpp)), etc.
+
+- For some high-level frameworks, a single backend usually handles both 'Platform' and 'Renderer' parts.<BR>
+  e.g. Allegro 5 ([imgui_impl_allegro5.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_allegro5.cpp)). If you end up creating a custom backend for your engine, you may want to do the same.
+
+An application usually combines one Platform backend + one Renderer backend + main Dear ImGui sources.
+For example, the [example_win32_directx11](https://github.com/ocornut/imgui/tree/master/examples/example_win32_directx11) application combines imgui_impl_win32.cpp + imgui_impl_dx11.cpp. There are 20+ examples in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder. See [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for details.
+
+**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
+
+### List of backends
+
+In the [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder:
+
+List of Platforms Backends:
+
+    imgui_impl_android.cpp    ; Android native app API
+    imgui_impl_glfw.cpp       ; GLFW (Windows, macOS, Linux, etc.) http://www.glfw.org/
+    imgui_impl_osx.mm         ; macOS native API (not as feature complete as glfw/sdl backends)
+    imgui_impl_sdl2.cpp       ; SDL2 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org
+    imgui_impl_sdl3.cpp       ; SDL3 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org (*EXPERIMENTAL UNTIL SDL3 IS RELEASED*)
+    imgui_impl_win32.cpp      ; Win32 native API (Windows)
+    imgui_impl_glut.cpp       ; GLUT/FreeGLUT (this is prehistoric software and absolutely not recommended today!)
+
+List of Renderer Backends:
+
+    imgui_impl_dx9.cpp        ; DirectX9
+    imgui_impl_dx10.cpp       ; DirectX10
+    imgui_impl_dx11.cpp       ; DirectX11
+    imgui_impl_dx12.cpp       ; DirectX12
+    imgui_impl_metal.mm       ; Metal (with ObjC)
+    imgui_impl_opengl2.cpp    ; OpenGL 2 (legacy, fixed pipeline <- don't use with modern OpenGL context)
+    imgui_impl_opengl3.cpp    ; OpenGL 3/4, OpenGL ES 2, OpenGL ES 3 (modern programmable pipeline)
+    imgui_impl_sdlrenderer2.cpp ; SDL_Renderer (optional component of SDL2 available from SDL 2.0.18+)
+    imgui_impl_sdlrenderer3.cpp ; SDL_Renderer (optional component of SDL3 available from SDL 3.0.0+)
+    imgui_impl_vulkan.cpp     ; Vulkan
+    imgui_impl_wgpu.cpp       ; WebGPU (web and desktop)
+
+List of high-level Frameworks Backends (combining Platform + Renderer):
+
+    imgui_impl_allegro5.cpp
+
+Emscripten is also supported!
+The SDL+GL, GLFW+GL and GLFW+WebGPU examples are all ready to build and run with Emscripten.
+
+### Backends for third-party frameworks, graphics API or other languages
+
+See https://github.com/ocornut/imgui/wiki/Bindings for the full list (e.g. Adventure Game Studio, Cinder, Cocos2d-x, Game Maker Studio2, Godot, LÖVE+LUA, Magnum, Monogame, Ogre, openFrameworks, OpenSceneGraph, SFML, Sokol, Unity, Unreal Engine and many others).
+
+### Recommended Backends
+
+If you are not sure which backend to use, the recommended platform/frameworks for portable applications:
+
+|Library |Website |Backend |Note |
+|--------|--------|--------|-----|
+| GLFW | https://github.com/glfw/glfw | imgui_impl_glfw.cpp | |
+| SDL2 | https://www.libsdl.org | imgui_impl_sdl2.cpp | |
+| Sokol | https://github.com/floooh/sokol | [util/sokol_imgui.h](https://github.com/floooh/sokol/blob/master/util/sokol_imgui.h) | Lower-level than GLFW/SDL |
+
+
+### Using a custom engine?
+
+You will likely be tempted to start by rewrite your own backend using your own custom/high-level facilities...<BR>
+Think twice!
+
+If you are new to Dear ImGui, first try using the existing backends as-is.
+You will save lots of time integrating the library.
+You can LATER decide to rewrite yourself a custom backend if you really need to.
+In most situations, custom backends have fewer features and more bugs than the standard backends we provide.
+If you want portability, you can use multiple backends and choose between them either at compile time
+or at runtime.
+
+**Example A**: your engine is built over Windows + DirectX11 but you have your own high-level rendering
+system layered over DirectX11.<BR>
+Suggestion: try using imgui_impl_win32.cpp + imgui_impl_dx11.cpp first.
+Once it works, if you really need it, you can replace the imgui_impl_dx11.cpp code with a
+custom renderer using your own rendering functions, and keep using the standard Win32 code etc.
+
+**Example B**: your engine runs on Windows, Mac, Linux and uses DirectX11, Metal, and Vulkan respectively.<BR>
+Suggestion: use multiple generic backends!
+Once it works, if you really need it, you can replace parts of backends with your own abstractions.
+
+**Example C**: your engine runs on platforms we can't provide public backends for (e.g. PS4/PS5, Switch),
+and you have high-level systems everywhere.<BR>
+Suggestion: try using a non-portable backend first (e.g. win32 + underlying graphics API) to get
+your desktop builds working first. This will get you running faster and get your acquainted with
+how Dear ImGui works and is setup. You can then rewrite a custom backend using your own engine API...
+
+Generally:
+It is unlikely you will add value to your project by creating your own backend.
+
+Also:
+The [multi-viewports feature](https://github.com/ocornut/imgui/wiki/Multi-Viewports) of the 'docking' branch allows
+Dear ImGui windows to be seamlessly detached from the main application window. This is achieved using an
+extra layer to the Platform and Renderer backends, which allows Dear ImGui to communicate platform-specific
+requests such as: "create an additional OS window", "create a render context", "get the OS position of this
+window" etc. See 'ImGuiPlatformIO' for details.
+Supporting the multi-viewports feature correctly using 100% of your own abstractions is more difficult
+than supporting single-viewport.
+If you decide to use unmodified imgui_impl_XXXX.cpp files, you can automatically benefit from
+improvements and fixes related to viewports and platform windows without extra work on your side.

Source/ThirdParty/ImGuiLibrary/Docs/CONTRIBUTING.md

@@ -0,0 +1,81 @@
+# Contributing Guidelines
+
+## Index
+
+- [Getting Started & General Advice](#getting-started--general-advice)
+- [Issues vs Discussions](#issues-vs-discussions)
+- [How to open an Issue](#how-to-open-an-issue)
+- [How to open a Pull Request](#how-to-open-a-pull-request)
+- [Copyright / Contributor License Agreement](#copyright--contributor-license-agreement)
+
+## Getting Started & General Advice
+
+- Article: [How To Ask Good Questions](https://bit.ly/3nwRnx1).
+- Please browse the [Wiki](https://github.com/ocornut/imgui/wiki) to find code snippets, links and other resources (e.g. [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started), [Useful extensions](https://github.com/ocornut/imgui/wiki/Useful-Extensions)).
+- Please read [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) if your question relates to setting up Dear ImGui.
+- Please read [docs/FAQ.md](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md).
+- Please read [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) if your question relates to fonts or text.
+- Please run `ImGui::ShowDemoWindow()` to explore the demo and its sources.
+- Please use the search function of your IDE to search for symbols and comments related to your situation.
+- Please use the search function of GitHub to look for similar topics (always include 'Closed' issues/pr in your search).
+- You may [browse issues by Labels](https://github.com/ocornut/imgui/labels).
+- Please use a web search engine to look for similar issues.
+- If you get a crash or assert, use a debugger to locate the line triggering it and read the comments around.
+- Please don't be a [Help Vampire](https://slash7.com/2006/12/22/vampires/).
+
+## 'Issues' vs 'Discussions'
+
+We are happy to use 'Issues' for many type of open-ended questions. We are encouraging 'Issues' becoming an enormous, centralized and cross-referenced database of Dear ImGui contents.
+
+Only if you:
+- Cannot BUILD or LINK examples.
+- Cannot BUILD, or LINK, or RUN Dear ImGui in your application or custom engine.
+- Cannot LOAD a font.
+
+Then please [use the Discussions forums](https://github.com/ocornut/imgui/discussions) instead of opening an issue.
+
+If Dear ImGui is successfully showing in your app and you have used Dear ImGui before, you can open an Issue. Any form of discussions is welcome as a new issue. 
+
+## How to open an issue
+
+You may use the Issue Tracker to submit bug reports, feature requests or suggestions. You may ask for help or advice as well. But **PLEASE CAREFULLY READ THIS WALL OF TEXT. ISSUES IGNORING THOSE GUIDELINES MAY BE CLOSED. USERS IGNORING THOSE GUIDELINES MIGHT BE BLOCKED.**
+
+Please do your best to clarify your request. The amount of incomplete or ambiguous requests due to people not following those guidelines is often overwhelming. Issues created without the requested information may be closed prematurely. Exceptionally entitled, impolite, or lazy requests may lead to bans.
+
+**PLEASE UNDERSTAND THAT OPEN-SOURCE SOFTWARE LIVES OR DIES BY THE AMOUNT OF ENERGY MAINTAINERS CAN SPARE. WE HAVE LOTS OF STUFF TO DO. THIS IS AN ATTENTION ECONOMY AND MANY LAZY OR MINOR ISSUES ARE HOGGING OUR ATTENTION AND DRAINING ENERGY, TAKING US AWAY FROM MORE IMPORTANT WORK.**
+
+Steps:
+
+- Article: [How To Ask Good Questions](https://bit.ly/3nwRnx1).
+- **PLEASE DO FILL THE REQUESTED NEW ISSUE TEMPLATE.** Including Dear ImGui version number, branch name, platform/renderer back-ends (imgui_impl_XXX files), operating system.
+- **Try to be explicit with your GOALS, your EXPECTATIONS and what you have tried**.  Be mindful of [The XY Problem](http://xyproblem.info/). What you have in mind or in your code is not obvious to other people. People frequently discuss problems and suggest incorrect solutions without first clarifying their goals. When requesting a new feature, please describe the usage context (how you intend to use it, why you need it, etc.). If you tried something and it failed, show us what you tried.
+- **Please INCLUDE CODE. Provide a Minimal, Complete, and Verifiable Example ([MCVE](https://stackoverflow.com/help/mcve)) to demonstrate your problem**. An ideal submission includes a small piece of code that anyone can paste into one of the examples applications (examples/../main.cpp) or demo (imgui_demo.cpp) to understand and reproduce it. **Narrowing your problem to its shortest and purest form is the easiest way to understand it, explain it and fix it**. Please test your shortened code to ensure it exhibits the problem. **Often while creating the MCVE you will solve the problem!** Many questions that are missing a standalone verifiable example are missing the actual cause of their issue in the description, which ends up wasting everyone's time.
+- **Attach screenshots (or GIF/video) to clarify the context**. They often convey useful information that is omitted by the description. You can drag pictures/files in the message edit box. Avoid using 3rd party image hosting services, prefer the long-term longevity of GitHub attachments (you can drag pictures into your post). On Windows, you can use [ScreenToGif](https://www.screentogif.com/) to easily capture .gif files.
+- **If you are discussing an assert or a crash, please provide a debugger callstack**. Never state "it crashes" without additional information. If you don't know how to use a debugger and retrieve a callstack, learning about it will be useful.
+- **Please make sure that your project has asserts enabled.** Calls to IM_ASSERT() are scattered in the code to help catch common issues. When an assert is triggered read the comments around it. By default IM_ASSERT() calls the standard assert() function. To verify that your asserts are enabled, add the line `IM_ASSERT(false);` in your main() function. Your application should display an error message and abort. If your application doesn't report an error, your asserts are disabled. 
+- Please state if you have made substantial modifications to your copy of Dear ImGui or the back-end.
+- If you are not calling Dear ImGui directly from C++, please provide information about your Language and the wrapper/binding you are using.
+- Be mindful that messages are being sent to the mailbox of "Watching" users. Try to proofread your messages before sending them. Edits are not seen by those users unless they browse the site.
+
+**Some unfortunate words of warning**
+- If you are involved in cheating schemes (e.g. DLL injection) for competitive online multiplayer games, please don't post here. We won't answer and you will be blocked. It doesn't matter if your question relates to said project. We've had too many of you and need to protect our time and sanity.
+- Due to frequent abuse of this service from the aforementioned users, if your GitHub account is anonymous and was created five minutes ago please understand that your post will receive more scrutiny and incomplete questions will be harshly dismissed.
+
+If you have been using Dear ImGui for a while or have been using C/C++ for several years or have demonstrated good behavior here, it is ok to not fulfill every item to the letter. Those are guidelines and experienced users or members of the community will know which information is useful in a given context.
+
+## How to open a Pull Request
+
+- **Please understand that by submitting a PR you are also submitting a request for the maintainer to review your code and then take over its maintenance.** PR should be crafted both in the interest of the end-users and also to ease the maintainer into understanding and accepting it. 
+- Many PRs are useful to demonstrate a need and a possible solution but aren't adequate for merging (causing other issues, not seeing other aspects of the big picture, etc.). In doubt, don't hesitate to push a PR because that is always the first step toward pointing toward a problem, and finding the mergeable solution! Even if a PR stays unmerged for a long time, its presence can be useful for other users and helps toward finding a general solution.
+- **When adding a feature,** please describe the usage context (how you intend to use it, why you need it, etc.). Be mindful of [The XY Problem](http://xyproblem.info/). 
+- **When fixing a warning or compilation problem,** please post the compiler log and specify the compiler version and platform you are using.
+- **Attach screenshots (or GIF/video) to clarify the context and demonstrate the feature at a glance.** You can drag pictures/files in the message edit box. Prefer the long-term longevity of GitHub attachments over 3rd party hosting (you can drag pictures into your post).
+- **Make sure your code follows the coding style already used in the codebase:** 4 spaces indentations (no tabs), `local_variable`, `FunctionName()`, `MemberName`, `// Text Comment`, `//CodeComment();`, C-style casts, etc.. We don't use modern C++ idioms and tend to use only a minimum of C++11 features. The applications under examples/ are generally less consistent because they sometimes try to mimic the coding style often adopted by a certain ecosystem (e.g. DirectX-related code tend to use the style of their sample). 
+- **Make sure you create a branch dedicated to the pull request**. In Git, 1 PR is associated to 1 branch. If you keep pushing to the same branch after you submitted the PR, your new commits will appear in the PR (we can still cherry-pick individual commits).
+
+## Copyright / Contributor License Agreement
+
+Any code you submit will become part of the repository and be distributed under the [Dear ImGui license](https://github.com/ocornut/imgui/blob/master/LICENSE.txt). By submitting code to the project you agree that the code is your work and that you can give it to the project.
+
+You also agree by submitting your code that you grant all transferrable rights to the code to the project maintainer, including for example re-licensing the code, modifying the code, and distributing it in source or binary forms. Specifically, this includes a requirement that you assign copyright to the project maintainer. For this reason, do not modify any copyright statements in files in any PRs.
+

Source/ThirdParty/ImGuiLibrary/Docs/EXAMPLES.md

@@ -0,0 +1,212 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Examples
+
+**The [examples/](https://github.com/ocornut/imgui/blob/master/examples) folder example applications (standalone, ready-to-build) for variety of
+platforms and graphics APIs.** They all use standard backends from the [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder (see [BACKENDS.md](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md)).
+
+The purpose of Examples is to showcase integration with backends, let you try Dear ImGui, and guide you toward
+integrating Dear ImGui in your own application/game/engine.
+**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
+
+You can find Windows binaries for some of those example applications at:
+  https://www.dearimgui.com/binaries
+
+
+### Getting Started
+
+Integration in a typical existing application, should take <20 lines when using standard backends.
+
+```cpp
+At initialization:
+  call ImGui::CreateContext()
+  call ImGui_ImplXXXX_Init() for each backend.
+
+At the beginning of your frame:
+  call ImGui_ImplXXXX_NewFrame() for each backend.
+  call ImGui::NewFrame()
+
+At the end of your frame:
+  call ImGui::Render()
+  call ImGui_ImplXXXX_RenderDrawData() for your Renderer backend.
+
+At shutdown:
+  call ImGui_ImplXXXX_Shutdown() for each backend.
+  call ImGui::DestroyContext()
+```
+
+Main resource:
+- Read **[Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) wiki guide** for detailed examples of how to integrate Dear ImGui in an existing application.
+
+Additional resources:
+- Read FAQ at https://www.dearimgui.com/faq
+- Read 'PROGRAMMER GUIDE' section in imgui.cpp.
+- Read the comments and instruction at the top of each file.
+
+If you are using any of the backends provided here, you can add the backends/imgui_impl_xxxx(.cpp,.h)
+files to your project and use as-in. Each imgui_impl_xxxx.cpp file comes with its own individual
+Changelog, so if you want to update them later it will be easier to catch up with what changed.
+
+
+### Examples Applications
+
+[example_allegro5/](https://github.com/ocornut/imgui/blob/master/examples/example_allegro5/) <BR>
+Allegro 5 example. <BR>
+= main.cpp + imgui_impl_allegro5.cpp
+
+[example_android_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_android_opengl3/) <BR>
+Android + OpenGL3 (ES) example. <BR>
+= main.cpp + imgui_impl_android.cpp + imgui_impl_opengl3.cpp
+
+[example_apple_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_metal/) <BR>
+OSX & iOS + Metal example. <BR>
+= main.m + imgui_impl_osx.mm + imgui_impl_metal.mm <BR>
+It is based on the "cross-platform" game template provided with Xcode as of Xcode 9.
+(NB: imgui_impl_osx.mm is currently not as feature complete as other platforms backends.
+You may prefer to use the GLFW Or SDL backends, which will also support Windows and Linux.)
+
+[example_apple_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_apple_opengl2/) <BR>
+OSX + OpenGL2 example. <BR>
+= main.mm + imgui_impl_osx.mm + imgui_impl_opengl2.cpp <BR>
+(NB: imgui_impl_osx.mm is currently not as feature complete as other platforms backends.
+ You may prefer to use the GLFW Or SDL backends, which will also support Windows and Linux.)
+
+[example_glfw_wgpu/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_wgpu/) <BR>
+GLFW + WebGPU example. Supports Emscripten (web) or Dawn (desktop) <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_wgpu.cpp
+Note that the 'example_glfw_opengl3' and 'example_sdl2_opengl3' examples also supports Emscripten!
+
+[example_glfw_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_metal/) <BR>
+GLFW (Mac) + Metal example. <BR>
+= main.mm + imgui_impl_glfw.cpp + imgui_impl_metal.mm
+
+[example_glfw_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_opengl2/) <BR>
+GLFW + OpenGL2 example (legacy, fixed pipeline). <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_opengl2.cpp <BR>
+**DO NOT USE THIS IF YOUR CODE/ENGINE IS USING MODERN GL or WEBGL (SHADERS, VBO, VAO, etc.)** <BR>
+This code is mostly provided as a reference to learn about Dear ImGui integration, because it is shorter.
+If your code is using GL3+ context or any semi modern GL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many GL attributes to their initial
+state, and might confuse your GPU driver. One star, not recommended.
+
+[example_glfw_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_opengl3/) <BR>
+GLFW (Win32, Mac, Linux) + OpenGL3+/ES2/ES3 example (modern, programmable pipeline). <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern GL calls and custom shaders.<BR>
+This support building with Emscripten and targeting WebGL.<BR>
+Prefer using that if you are using modern GL or WebGL in your application.
+
+[example_glfw_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_vulkan/) <BR>
+GLFW (Win32, Mac, Linux) + Vulkan example. <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_vulkan.cpp <BR>
+This is quite long and tedious, because: Vulkan.
+For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
+
+[example_glut_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_glut_opengl2/) <BR>
+GLUT (e.g., FreeGLUT on Linux/Windows, GLUT framework on OSX) + OpenGL2 example. <BR>
+= main.cpp + imgui_impl_glut.cpp + imgui_impl_opengl2.cpp <BR>
+Note that GLUT/FreeGLUT is largely obsolete software, prefer using GLFW or SDL.
+
+[example_null/](https://github.com/ocornut/imgui/blob/master/examples/example_null/) <BR>
+Null example, compile and link imgui, create context, run headless with no inputs and no graphics output. <BR>
+= main.cpp <BR>
+This is used to quickly test compilation of core imgui files in as many setups as possible.
+Because this application doesn't create a window nor a graphic context, there's no graphics output.
+
+[example_sdl2_directx11/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_directx11/) <BR>
+SDL2 + DirectX11 example, Windows only. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_dx11.cpp <BR>
+This to demonstrate usage of DirectX with SDL2.
+
+[example_sdl2_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_metal/) <BR>
+SDL2 + Metal example, Mac only. <BR>
+= main.mm + imgui_impl_sdl2.cpp + imgui_impl_metal.mm
+
+[example_sdl2_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_opengl2/) <BR>
+SDL2 (Win32, Mac, Linux etc.) + OpenGL example (legacy, fixed pipeline). <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_opengl2.cpp <BR>
+**DO NOT USE OPENGL2 CODE IF YOUR CODE/ENGINE IS USING GL OR WEBGL (SHADERS, VBO, VAO, etc.)** <BR>
+This code is mostly provided as a reference to learn about Dear ImGui integration, because it is shorter.
+If your code is using GL3+ context or any semi modern GL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many GL attributes to their initial
+state, and might confuse your GPU driver. One star, not recommended.
+
+[example_sdl2_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_opengl3/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + OpenGL3+/ES2/ES3 example. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern GL calls and custom shaders. <BR>
+This support building with Emscripten and targeting WebGL.<BR>
+Prefer using that if you are using modern GL or WebGL in your application.
+
+[example_sdl2_sdlrenderer2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_sdlrenderer2/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + SDL_Renderer for SDL2 (most graphics backends are supported underneath) <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_sdlrenderer.cpp <BR>
+This requires SDL 2.0.18+ (released November 2021) <BR>
+
+[example_sdl2_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_vulkan/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + Vulkan example. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_vulkan.cpp <BR>
+This is quite long and tedious, because: Vulkan. <BR>
+For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
+
+[example_win32_directx9/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx9/) <BR>
+DirectX9 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx9.cpp
+
+[example_win32_directx10/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx10/) <BR>
+DirectX10 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx10.cpp
+
+[example_win32_directx11/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx11/) <BR>
+DirectX11 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx11.cpp
+
+[example_win32_directx12/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx12/) <BR>
+DirectX12 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx12.cpp <BR>
+This is quite long and tedious, because: DirectX12.
+
+[example_win32_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_opengl3/) <BR>
+Raw Windows + OpenGL3 + example (modern, programmable pipeline) <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_opengl3.cpp <BR>
+
+
+### Miscellaneous
+
+**Building**
+
+Unfortunately nowadays it is still tedious to create and maintain portable build files using external
+libraries (the kind we're using here to create a window and render 3D triangles) without relying on
+third party software and build systems. For most examples here we choose to provide:
+ - Makefiles for Linux/OSX
+ - Batch files for Visual Studio 2008+
+ - A .sln project file for Visual Studio 2012+
+ - Xcode project files for the Apple examples
+Please let us know if they don't work with your setup!
+You can probably just import the imgui_impl_xxx.cpp/.h files into your own codebase or compile those
+directly with a command-line compiler.
+
+If you are interested in using Cmake to build and links examples, see:
+  https://github.com/ocornut/imgui/pull/1713 and https://github.com/ocornut/imgui/pull/3027
+
+**About mouse cursor latency**
+
+Dear ImGui has no particular extra lag for most behaviors,
+e.g. the last value passed to 'io.AddMousePosEvent()' before NewFrame() will result in windows being moved
+to the right spot at the time of EndFrame()/Render(). At 60 FPS your experience should be pleasant.
+
+However, consider that OS mouse cursors are typically drawn through a very specific hardware accelerated
+path and will feel smoother than the majority of contents rendered via regular graphics API (including,
+but not limited to Dear ImGui windows). Because UI rendering and interaction happens on the same plane
+as the mouse, that disconnect may be jarring to particularly sensitive users.
+You may experiment with enabling the io.MouseDrawCursor flag to request Dear ImGui to draw a mouse cursor
+using the regular graphics API, to help you visualize the difference between a "hardware" cursor and a
+regularly rendered software cursor.
+However, rendering a mouse cursor at 60 FPS will feel sluggish so you likely won't want to enable that at
+all times. It might be beneficial for the user experience to switch to a software rendered cursor _only_
+when an interactive drag is in progress.
+
+Note that some setup or GPU drivers are likely to be causing extra display lag depending on their settings.
+If you feel that dragging windows feels laggy and you are not sure what the cause is: try to build a simple
+drawing a flat 2D shape directly under the mouse cursor!
+

Source/ThirdParty/ImGuiLibrary/Docs/FAQ.md

@@ -0,0 +1,709 @@
+# FAQ (Frequently Asked Questions)
+
+You may link to this document using short form:
+  https://www.dearimgui.com/faq
+or its real address:
+  https://github.com/ocornut/imgui/blob/master/docs/FAQ.md
+or view this file with any Markdown viewer.
+
+
+## Index
+
+| **Q&A: Basics** |
+:---------------------------------------------------------- |
+| [Where is the documentation?](#q-where-is-the-documentation) |
+| [What is this library called?](#q-what-is-this-library-called) |
+| [Which version should I get?](#q-which-version-should-i-get) |
+| **Q&A: Integration** |
+| **[How to get started?](#q-how-to-get-started)** |
+| **[How can I tell whether to dispatch mouse/keyboard to Dear ImGui or my application?](#q-how-can-i-tell-whether-to-dispatch-mousekeyboard-to-dear-imgui-or-my-application)** |
+| [How can I enable keyboard or gamepad controls?](#q-how-can-i-enable-keyboard-or-gamepad-controls) |
+| [How can I use this on a machine without mouse, keyboard or screen? (input share, remote display)](#q-how-can-i-use-this-on-a-machine-without-mouse-keyboard-or-screen-input-share-remote-display) |
+| [I integrated Dear ImGui in my engine and little squares are showing instead of text...](#q-i-integrated-dear-imgui-in-my-engine-and-little-squares-are-showing-instead-of-text) |
+| [I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around...](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-clipping-or-disappearing-when-i-move-windows-around) |
+| [I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries...](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-displaying-outside-their-expected-windows-boundaries) |
+| **Q&A: Usage** |
+| **[About the ID Stack system..<br>Why is my widget not reacting when I click on it?<br>Why is the wrong widget reacting when I click on one?<br>How can I have widgets with an empty label?<br>How can I have multiple widgets with the same label?<br>How can I have multiple windows with the same label?](#q-about-the-id-stack-system)** |
+| [How can I display an image? What is ImTextureID, how does it work?](#q-how-can-i-display-an-image-what-is-imtextureid-how-does-it-work)|
+| [How can I use maths operators with ImVec2?](#q-how-can-i-use-maths-operators-with-imvec2) |
+| [How can I use my own maths types instead of ImVec2/ImVec4?](#q-how-can-i-use-my-own-maths-types-instead-of-imvec2imvec4) |
+| [How can I interact with standard C++ types (such as std::string and std::vector)?](#q-how-can-i-interact-with-standard-c-types-such-as-stdstring-and-stdvector) |
+| [How can I display custom shapes? (using low-level ImDrawList API)](#q-how-can-i-display-custom-shapes-using-low-level-imdrawlist-api) |
+| **Q&A: Fonts, Text** |
+| [How should I handle DPI in my application?](#q-how-should-i-handle-dpi-in-my-application) |
+| [How can I load a different font than the default?](#q-how-can-i-load-a-different-font-than-the-default) |
+| [How can I easily use icons in my application?](#q-how-can-i-easily-use-icons-in-my-application) |
+| [How can I load multiple fonts?](#q-how-can-i-load-multiple-fonts) |
+| [How can I display and input non-Latin characters such as Chinese, Japanese, Korean, Cyrillic?](#q-how-can-i-display-and-input-non-latin-characters-such-as-chinese-japanese-korean-cyrillic) |
+| **Q&A: Concerns** |
+| [Who uses Dear ImGui?](#q-who-uses-dear-imgui) |
+| [Can you create elaborate/serious tools with Dear ImGui?](#q-can-you-create-elaborateserious-tools-with-dear-imgui)  |
+| [Can you reskin the look of Dear ImGui?](#q-can-you-reskin-the-look-of-dear-imgui) |
+| [Why using C++ (as opposed to C)?](#q-why-using-c-as-opposed-to-c) |
+| **Q&A: Community** |
+| [How can I help?](#q-how-can-i-help) |
+
+
+# Q&A: Basics
+
+### Q: Where is the documentation?
+
+**This library is poorly documented at the moment and expects the user to be acquainted with C/C++.**
+- The [Wiki](https://github.com/ocornut/imgui/wiki) is a hub to many resources and links.
+- Handy [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide to integrate Dear ImGui in an existing application.
+- 20+ standalone example applications using e.g. OpenGL/DirectX are provided in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder to explain how to integrate Dear ImGui with your own engine/application. You can run those applications and explore them.
+- See demo code in [imgui_demo.cpp](https://github.com/ocornut/imgui/blob/master/imgui_demo.cpp) and particularly the `ImGui::ShowDemoWindow()` function. The demo covers most features of Dear ImGui, so you can read the code and see its output.
+- See documentation: [Backends](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md), [Examples](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md), [Fonts](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md).
+- See documentation and comments at the top of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp) + general API comments in [imgui.h](https://github.com/ocornut/imgui/blob/master/imgui.h).
+- The [Glossary](https://github.com/ocornut/imgui/wiki/Glossary) page may be useful.
+- The [Issues](https://github.com/ocornut/imgui/issues) and [Discussions](https://github.com/ocornut/imgui/discussions) sections can be searched for past questions and issues.
+- Your programming IDE is your friend, find the type or function declaration to find comments associated with it.
+- The `ImGui::ShowMetricsWindow()` function exposes lots of internal information and tools. Although it is primarily designed as a debugging tool, having access to that information tends to help understands concepts.
+
+##### [Return to Index](#index)
+
+---
+
+### Q. What is this library called?
+
+**This library is called Dear ImGui**. Please refer to it as Dear ImGui (not ImGui, not IMGUI).
+
+(The library misleadingly started its life in 2014 as "ImGui" due to the fact that I didn't give it a proper name when I released 1.0, and had no particular expectation that it would take off. However, the term IMGUI (immediate-mode graphical user interface) was coined before and is being used in variety of other situations e.g. Unity uses it own implementation of the IMGUI paradigm. To reduce the ambiguity without affecting existing code bases, I have decided in December 2015 a fully qualified name "Dear ImGui" for this library.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Which version should I get?
+I occasionally tag [Releases](https://github.com/ocornut/imgui/releases) but it is generally safe and recommended to sync to master/latest. The library is fairly stable and regressions tend to be fixed fast when reported.
+
+You may use the ['docking'](https://github.com/ocornut/imgui/tree/docking) branch which includes:
+- [Docking features](https://github.com/ocornut/imgui/wiki/Docking)
+- [Multi-viewport features](https://github.com/ocornut/imgui/wiki/Multi-Viewports)
+
+Many projects are using this branch and it is kept in sync with master regularly.
+
+##### [Return to Index](#index)
+
+----
+
+# Q&A: Integration
+
+### Q: How to get started?
+
+Read [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started). <BR>
+Read [EXAMPLES.md](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md). <BR>
+Read [BACKENDS.md](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md). <BR>
+Read `PROGRAMMER GUIDE` section of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp). <BR>
+The [Wiki](https://github.com/ocornut/imgui/wiki) is a hub to many resources and links.
+
+For first-time users having issues compiling/linking/running or issues loading fonts, please use [GitHub Discussions](https://github.com/ocornut/imgui/discussions).
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I tell whether to dispatch mouse/keyboard to Dear ImGui or my application?
+
+You can read the `io.WantCaptureMouse`, `io.WantCaptureKeyboard` and `io.WantTextInput` flags from the ImGuiIO structure.
+- When `io.WantCaptureMouse` is set, you need to discard/hide the mouse inputs from your underlying application.
+- When `io.WantCaptureKeyboard` is set, you need to discard/hide the keyboard inputs from your underlying application.
+- When `io.WantTextInput` is set, you can notify your OS/engine to popup an on-screen keyboard, if available (e.g. on a mobile phone, or console OS).
+
+Important: you should always pass your mouse/keyboard inputs to Dear ImGui, regardless of the value `io.WantCaptureMouse`/`io.WantCaptureKeyboard`. This is because e.g. we need to detect that you clicked in the void to unfocus its own windows, and other reasons.
+
+```cpp
+void MyLowLevelMouseButtonHandler(int button, bool down)
+{
+    // (1) ALWAYS forward mouse data to ImGui! This is automatic with default backends. With your own backend:
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMouseButtonEvent(button, down);
+
+    // (2) ONLY forward mouse data to your underlying app/game.
+    if (!io.WantCaptureMouse)
+        my_game->HandleMouseData(...);
+}
+```
+
+**Note:** The `io.WantCaptureMouse` is more correct that any manual attempt to "check if the mouse is hovering a window" (don't do that!). It handles mouse dragging correctly (both dragging that started over your application or over a Dear ImGui window) and handle e.g. popup and modal windows blocking inputs.
+
+**Note:** Text input widget releases focus on the "KeyDown" event of the Return key, so the subsequent "KeyUp" event that your application receive will typically have `io.WantCaptureKeyboard == false`. Depending on your application logic it may or not be inconvenient to receive that KeyUp event. You might want to track which key-downs were targeted for Dear ImGui, e.g. with an array of bool, and filter out the corresponding key-ups.)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I enable keyboard or gamepad controls?
+- The gamepad/keyboard navigation is fairly functional and keeps being improved. The initial focus was to support game controllers, but keyboard is becoming increasingly and decently usable. Gamepad support is particularly useful to use Dear ImGui on a game console (e.g. PS4, Switch, XB1) without a mouse connected!
+- Keyboard: set `io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard` to enable.
+- Gamepad: set `io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad` to enable (with a supporting backend).
+- See [Control Sheets for Gamepads](https://www.dearimgui.com/controls_sheets) (reference PNG/PSD for PS4, XB1, Switch gamepads).
+- See `USING GAMEPAD/KEYBOARD NAVIGATION CONTROLS` section of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp) for more details.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use this on a machine without mouse, keyboard or screen? (input share, remote display)
+- You can share your computer mouse seamlessly with your console/tablet/phone using solutions such as [Synergy](https://symless.com/synergy)
+This is the preferred solution for developer productivity.
+In particular, the [micro-synergy-client repository](https://github.com/symless/micro-synergy-client) has simple
+and portable source code (uSynergy.c/.h) for a small embeddable client that you can use on any platform to connect
+to your host computer, based on the Synergy 1.x protocol. Make sure you download the Synergy 1 server on your computer.
+Console SDK also sometimes provide equivalent tooling or wrapper for Synergy-like protocols.
+- Game console users: consider emulating a mouse cursor with DualShock4 touch pad or a spare analog stick as a mouse-emulation fallback.
+- You may also use a third party solution such as [netImgui](https://github.com/sammyfreg/netImgui), [Remote ImGui](https://github.com/JordiRos/remoteimgui) or [imgui-ws](https://github.com/ggerganov/imgui-ws) which sends the vertices to render over the local network, allowing you to use Dear ImGui even on a screen-less machine. See [Wiki](https://github.com/ocornut/imgui/wiki) index for most details.
+- For touch inputs, you can increase the hit box of widgets (via the `style.TouchPadding` setting) to accommodate for the lack of precision of touch inputs, but it is recommended you use a mouse or gamepad to allow optimizing for screen real-estate and precision.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: I integrated Dear ImGui in my engine and little squares are showing instead of text...
+Your renderer backend is not using the font texture correctly or it hasn't been uploaded to the GPU.
+- If this happens using the standard backends: A) have you modified the font atlas after `ImGui_ImplXXX_NewFrame()`? B) maybe the texture failed to upload, which **can if your texture atlas is too big**. Also see [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md).
+- If this happens with a custom backend: make sure you have uploaded the font texture to the GPU, that all shaders are rendering states are setup properly (e.g. texture is bound). Compare your code to existing backends and use a graphics debugger such as [RenderDoc](https://renderdoc.org) to debug your rendering states.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around...
+### Q: I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries...
+You are probably mishandling the clipping rectangles in your render function.
+Each draw command needs the triangle rendered using the clipping rectangle provided in the ImDrawCmd structure (`ImDrawCmd->CllipRect`).
+Rectangles provided by Dear ImGui are defined as
+`(x1=left,y1=top,x2=right,y2=bottom)`
+and **NOT** as
+`(x1,y1,width,height)`.
+Refer to rendering backends in the [backends/](https://github.com/ocornut/imgui/tree/master/backends) folder for references of how to handle the `ClipRect` field.
+For example, the [DirectX11 backend](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp) does this:
+```cpp
+// Project scissor/clipping rectangles into framebuffer space
+ImVec2 clip_off = draw_data->DisplayPos;
+ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+    continue;
+
+// Apply scissor/clipping rectangle
+const D3D11_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+ctx->RSSetScissorRects(1, &r);
+```
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Usage
+
+### Q: About the ID Stack system...
+### Q: Why is my widget not reacting when I click on it?
+### Q: Why is the wrong widget reacting when I click on one?
+### Q: How can I have widgets with an empty label?
+### Q: How can I have multiple widgets with the same label?
+### Q: How can I have multiple windows with the same label?
+
+**USING THE SAME LABEL+ID IS THE MOST COMMON USER MISTAKE!**
+<br>**USING AN EMPTY LABEL IS THE SAME AS USING THE SAME LABEL AS YOUR PARENT WIDGET!**
+<table>
+<tr>
+<td><img src="https://github.com/user-attachments/assets/776a8315-1164-4178-9a8c-df52e0ff28aa"></td>
+<td>
+<pre lang="cpp">
+ImGui::Begin("Incorrect!");
+ImGui::DragFloat2("My value", &objects[0]->pos.x);
+ImGui::DragFloat2("My value", &objects[1]->pos.x);
+ImGui::DragFloat2("My value", &objects[2]->pos.x);
+ImGui::End();
+&nbsp;
+ImGui::Begin("Correct!");
+ImGui::DragFloat2("My value", &objects[0]->pos.x);
+ImGui::DragFloat2("My value##2", &objects[1]->pos.x);
+ImGui::DragFloat2("My value##3", &objects[2]->pos.x);
+ImGui::End();
+&nbsp;
+ImGui::Begin("Also Correct!");
+for (int n = 0; n < 3; n++)
+{
+    ImGui::PushID(n);
+    ImGui::DragFloat2("My value", &objects[n]->pos.x);
+    ImGui::PopID();
+}
+ImGui::End();
+</pre>
+</td>
+</tr>    
+</table>
+
+A primer on labels and the ID Stack...
+
+Dear ImGui internally needs to uniquely identify UI elements.
+Elements that are typically not clickable (such as calls to the Text functions) don't need an ID.
+Interactive widgets (such as calls to Button buttons) need a unique ID.
+
+**Unique IDs are used internally to track active widgets and occasionally associate state to widgets.<BR>
+Unique IDs are implicitly built from the hash of multiple elements that identify the "path" to the UI element.**
+
+Since Dear ImGui 1.85, you can use `Demo>Tools>ID Stack Tool` or call `ImGui::ShowIDStackToolWindow()`. The tool display intermediate values leading to the creation of a unique ID, making things easier to debug and understand.
+
+![Stack tool](https://user-images.githubusercontent.com/8225057/136235657-a0ea5665-dcd1-423f-9be6-dc3f8ced8f12.png)
+
+- Unique ID are often derived from a string label and at minimum scoped within their host window:
+```cpp
+Begin("MyWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyWindow", "OK")
+Button("Cancel");      // Label = "Cancel", ID = hash of ("MyWindow", "Cancel")
+End();
+```
+- Other elements such as tree nodes, etc. also pushes to the ID stack:
+```cpp
+Begin("MyWindow");
+if (TreeNode("MyTreeNode"))
+{
+    Button("OK");      // Label = "OK",     ID = hash of ("MyWindow", "MyTreeNode", "OK")
+    TreePop();
+}
+End();
+```
+- Two items labeled "OK" in different windows or different tree locations won't collide:
+```cpp
+Begin("MyFirstWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyFirstWindow", "OK")
+End();
+Begin("MyOtherWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyOtherWindow", "OK")
+End();
+```
+
+- If you have a same ID twice in the same location, you'll have a conflict:
+```cpp
+Begin("MyWindow");
+Button("OK");
+Button("OK");      // ERROR: ID collision with the first button! Interacting with either button will trigger the first one.
+Button("");        // ERROR: ID collision with Begin("MyWindow")!
+End();
+```
+Fear not! This is easy to solve and there are many ways to solve it!
+
+- Solving ID conflict in a simple/local context:
+When passing a label you can optionally specify extra ID information within the string itself.
+Use "##" to pass a complement to the ID that won't be visible to the end-user.
+This helps solve the simple collision cases when you know e.g. at compilation time which items
+are going to be created:
+```cpp
+Begin("MyWindow");
+Button("Play");        // Label = "Play",   ID = hash of ("MyWindow", "Play")
+Button("Play##foo1");  // Label = "Play",   ID = hash of ("MyWindow", "Play##foo1")  // Different from other buttons
+Button("Play##foo2");  // Label = "Play",   ID = hash of ("MyWindow", "Play##foo2")  // Different from other buttons
+Button("##foo");       // Label = "",       ID = hash of ("MyWindow", "##foo")       // Different from window
+End();
+```
+- If you want to completely hide the label, but still need an ID:
+```cpp
+Checkbox("##On", &b);  // Label = "",       ID = hash of (..., "##On")   // No visible label, just a checkbox!
+```
+- Occasionally/rarely you might want to change a label while preserving a constant ID. This allows
+you to animate labels. For example, you may want to include varying information in a window title bar,
+but windows are uniquely identified by their ID. Use "###" to pass a label that isn't part of ID:
+```cpp
+Button("Hello###ID");  // Label = "Hello",  ID = hash of (..., "###ID")
+Button("World###ID");  // Label = "World",  ID = hash of (..., "###ID")  // Same ID, different label
+
+sprintf(buf, "My game (%f FPS)###MyGame", fps);
+Begin(buf);            // Variable title,   ID = hash of "MyGame"
+```
+- Solving ID conflict in a more general manner:
+Use `PushID()` / `PopID()` to create scopes and manipulate the ID stack, as to avoid ID conflicts
+within the same window. This is the most convenient way of distinguishing ID when iterating and
+creating many UI elements programmatically.
+You can push a pointer, a string, or an integer value into the ID stack.
+Remember that IDs are formed from the concatenation of _everything_ pushed into the ID stack.
+At each level of the stack, we store the seed used for items at this level of the ID stack.
+```cpp
+Begin("Window");
+for (int i = 0; i < 100; i++)
+{
+  PushID(i);           // Push i to the id tack
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", i, "Click")
+  PopID();
+}
+for (int i = 0; i < 100; i++)
+{
+  MyObject* obj = Objects[i];
+  PushID(obj);
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", obj pointer, "Click")
+  PopID();
+}
+for (int i = 0; i < 100; i++)
+{
+  MyObject* obj = Objects[i];
+  PushID(obj->Name);
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", obj->Name, "Click")
+  PopID();
+}
+End();
+```
+- You can stack multiple prefixes into the ID stack:
+```cpp
+Button("Click");       // Label = "Click",  ID = hash of (..., "Click")
+PushID("node");
+  Button("Click");     // Label = "Click",  ID = hash of (..., "node", "Click")
+  PushID(my_ptr);
+    Button("Click");   // Label = "Click",  ID = hash of (..., "node", my_ptr, "Click")
+  PopID();
+PopID();
+```
+- Tree nodes implicitly create a scope for you by calling `PushID()`:
+```cpp
+Button("Click");       // Label = "Click",  ID = hash of (..., "Click")
+if (TreeNode("node"))  // <-- this function call will do a PushID() for you (unless instructed not to, with a special flag)
+{
+  Button("Click");     // Label = "Click",  ID = hash of (..., "node", "Click")
+  TreePop();
+}
+```
+
+When working with trees, IDs are used to preserve the open/close state of each tree node.
+Depending on your use cases you may want to use strings, indices, or pointers as ID.
+- e.g. when following a single pointer that may change over time, using a static string as ID
+will preserve your node open/closed state when the targeted object change.
+- e.g. when displaying a list of objects, using indices or pointers as ID will preserve the
+node open/closed state differently. See what makes more sense in your situation!
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display an image? What is ImTextureID, how does it work?
+
+Short explanation:
+- Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki).
+- You may use functions such as `ImGui::Image()`, `ImGui::ImageButton()` or lower-level `ImDrawList::AddImage()` to emit draw calls that will use your own textures.
+- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as an opaque ImTextureID value.
+- By default ImTextureID can store up to 64-bits. You may `#define` it to a custom type/structure if you need.
+- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason), but the examples linked above may be useful references.
+
+**Please read documentations or tutorials on your graphics API to understand how to display textures on the screen before moving onward.**
+
+Long explanation:
+- Dear ImGui's job is to create "meshes", defined in a renderer-agnostic format made of draw commands and vertices. At the end of the frame, those meshes (ImDrawList) will be displayed by your rendering function. They are made up of textured polygons and the code to render them is generally fairly short (a few dozen lines). In the examples/ folder, we provide functions for popular graphics APIs (OpenGL, DirectX, etc.).
+- Each rendering function decides on a data type to represent "textures". The concept of what is a "texture" is entirely tied to your underlying engine/graphics API.
+ We carry the information to identify a "texture" in the ImTextureID type.
+ImTextureID default to ImU64 aka 8 bytes worth of data: just enough to store one pointer or integer of your choice.
+Dear ImGui doesn't know or understand what you are storing in ImTextureID, it merely passes ImTextureID values until they reach your rendering function.
+- In the [examples/](https://github.com/ocornut/imgui/tree/master/examples) backends, for each graphics API we decided on a type that is likely to be a good representation for specifying an image from the end-user perspective. This is what the _examples_ rendering functions are using:
+```cpp
+OpenGL:
+- ImTextureID should contains 'GLuint' (GL texture identifier).
+- See ImGui_ImplOpenGL3_RenderDrawData() function in imgui_impl_opengl3.cpp
+```
+```cpp
+DirectX9:
+- ImTextureID should contain a 'LPDIRECT3DTEXTURE9' (pointer).
+- See ImGui_ImplDX9_RenderDrawData() function in imgui_impl_dx9.cpp
+```
+```cpp
+DirectX11:
+- ImTextureID should contain a 'ID3D11ShaderResourceView*' (pointer)
+- See ImGui_ImplDX11_RenderDrawData() function in imgui_impl_dx11.cpp
+```
+```cpp
+DirectX12:
+- ImTextureID should contain a 'D3D12_GPU_DESCRIPTOR_HANDLE' (always 64-bits)
+- See ImGui_ImplDX12_RenderDrawData() function in imgui_impl_dx12.cpp
+```
+For example, in the OpenGL example backend we store raw OpenGL texture identifier (GLuint) inside ImTextureID.
+Whereas in the DirectX11 example backend we store a pointer to ID3D11ShaderResourceView inside ImTextureID, which is a higher-level structure tying together both the texture and information about its format and how to read it.
+
+- If you have a custom engine built over e.g. OpenGL, instead of passing GLuint around you may decide to use a high-level data type to carry information about the texture as well as how to display it (shaders, etc.). The decision of what to use as ImTextureID can always be made better by knowing how your codebase is designed. If your engine has high-level data types for "textures" and "material" then you may want to use them.
+If you are starting with OpenGL or DirectX or Vulkan and haven't built much of a rendering engine over them, keeping the default ImTextureID representation suggested by the example backends is probably the best choice.
+(Advanced users may also decide to keep a low-level type in ImTextureID, use ImDrawList callback and pass information to their renderer)
+
+User code may do:
+```cpp
+// Cast our texture type to ImTextureID
+MyTexture* texture = g_CoffeeTableTexture;
+ImGui::Image((ImTextureID)(intptr_t)texture, ImVec2(texture->Width, texture->Height));
+```
+The renderer function called after ImGui::Render() will receive that same value that the user code passed:
+```cpp
+// Cast ImTextureID stored in the draw command as our texture type
+MyTexture* texture = (MyTexture*)(intptr_t)pcmd->GetTexID();
+MyEngineBindTexture2D(texture);
+```
+Once you understand this design, you will understand that loading image files and turning them into displayable textures is not within the scope of Dear ImGui.
+This is by design and is a good thing because it means your code has full control over your data types and how you display them.
+If you want to display an image file (e.g. PNG file) on the screen, please refer to documentation and tutorials for the graphics API you are using.
+
+Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki) to find simplified examples for loading textures with OpenGL, DirectX9 and DirectX11.
+
+C/C++ tip: a u64 is 8 bytes. You may safely store any pointer or integer into it by casting your value to ImTextureID, and vice-versa.
+Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID.
+Here are some examples:
+```cpp
+GLuint my_tex = XXX;
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_tex;                     // cast a GLuint into a ImTextureID (we don't take its address! we just copy the address)
+my_tex = (GLuint)(intptr_t)my_imtexid;                          // cast a ImTextureID into a GLuint
+
+ID3D11ShaderResourceView* my_dx11_srv = XXX;
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_dx11_srv;                // cast a ID3D11ShaderResourceView* into an opaque ImTextureID
+my_dx11_srv = (ID3D11ShaderResourceView*)(intptr_t)_my_imtexid; // cast a ImTextureID into a ID3D11ShaderResourceView*
+```
+Finally, you may call `ImGui::ShowMetricsWindow()` to explore/visualize/understand how the ImDrawList are generated.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use maths operators with ImVec2?
+
+We do not export maths operators by default in imgui.h in order to not conflict with the use of your own maths types and maths operators. As a convenience, you may use `#define IMGUI_DEFINE_MATH_OPERATORS` + `#include "imgui.h"` to access our basic maths operators.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use my own maths types instead of ImVec2/ImVec4?
+
+You can setup your [imconfig.h](https://github.com/ocornut/imgui/blob/master/imconfig.h) file with `IM_VEC2_CLASS_EXTRA`/`IM_VEC4_CLASS_EXTRA` macros to add implicit type conversions to our own maths types.
+This way you will be able to use your own types everywhere, e.g. passing `MyVector2` or `glm::vec2` to ImGui functions instead of `ImVec2`.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I interact with standard C++ types (such as std::string and std::vector)?
+- Being highly portable (backends/bindings for several languages, frameworks, programming styles, obscure or older platforms/compilers), and aiming for compatibility & performance suitable for every modern real-time game engine, Dear ImGui does not use any of std C++ types. We use raw types (e.g. char* instead of std::string) because they adapt to more use cases.
+- To use ImGui::InputText() with a std::string or any resizable string class, see [misc/cpp/imgui_stdlib.h](https://github.com/ocornut/imgui/blob/master/misc/cpp/imgui_stdlib.h).
+- To use combo boxes and list boxes with `std::vector` or any other data structure: the `BeginCombo()/EndCombo()` API
+lets you iterate and submit items yourself, so does the `ListBoxHeader()/ListBoxFooter()` API.
+Prefer using them over the old and awkward `Combo()/ListBox()` api.
+- Generally for most high-level types you should be able to access the underlying data type.
+You may write your own one-liner wrappers to facilitate user code (tip: add new functions in ImGui:: namespace from your code).
+- Dear ImGui applications often need to make intensive use of strings. It is expected that many of the strings you will pass
+to the API are raw literals (free in C/C++) or allocated in a manner that won't incur a large cost on your application.
+Please bear in mind that using `std::string` on applications with a large amount of UI may incur unsatisfactory performances.
+Modern implementations of `std::string` often include small-string optimization (which is often a local buffer) but those
+are not configurable and not the same across implementations.
+- If you are finding your UI traversal cost to be too large, make sure your string usage is not leading to an excessive amount
+of heap allocations. Consider using literals, statically sized buffers, and your own helper functions. A common pattern
+is that you will need to build lots of strings on the fly, and their maximum length can be easily scoped ahead.
+One possible implementation of a helper to facilitate printf-style building of strings: https://github.com/ocornut/Str
+This is a small helper where you can instance strings with configurable local buffers length. Many game engines will
+provide similar or better string helpers.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display custom shapes? (using low-level ImDrawList API)
+
+- You can use the low-level `ImDrawList` api to render shapes within a window.
+```cpp
+ImGui::Begin("My shapes");
+
+ImDrawList* draw_list = ImGui::GetWindowDrawList();
+
+// Get the current ImGui cursor position
+ImVec2 p = ImGui::GetCursorScreenPos();
+
+// Draw a red circle
+draw_list->AddCircleFilled(ImVec2(p.x + 50, p.y + 50), 30.0f, IM_COL32(255, 0, 0, 255));
+
+// Draw a 3 pixel thick yellow line
+draw_list->AddLine(ImVec2(p.x, p.y), ImVec2(p.x + 100.0f, p.y + 100.0f), IM_COL32(255, 255, 0, 255), 3.0f);
+
+// Advance the ImGui cursor to claim space in the window (otherwise the window will appear small and needs to be resized)
+ImGui::Dummy(ImVec2(200, 200));
+
+ImGui::End();
+```
+![ImDrawList usage](https://raw.githubusercontent.com/wiki/ocornut/imgui/tutorials/CustomRendering01.png)
+
+- Refer to "Demo > Examples > Custom Rendering" in the demo window and read the code of `ShowExampleAppCustomRendering()` in `imgui_demo.cpp` from more examples.
+- To generate colors: you can use the macro `IM_COL32(255,255,255,255)` to generate them at compile time, or use `ImGui::GetColorU32(IM_COL32(255,255,255,255))` or `ImGui::GetColorU32(ImVec4(1.0f,1.0f,1.0f,1.0f))` to generate a color that is multiplied by the current value of `style.Alpha`.
+- Math operators: if you have setup `IM_VEC2_CLASS_EXTRA` in `imconfig.h` to bind your own math types, you can use your own math types and their natural operators instead of ImVec2. ImVec2 by default doesn't export any math operators in the public API. You may use `#define IMGUI_DEFINE_MATH_OPERATORS` `#include "imgui.h"` to use our math operators, but instead prefer using your own math library and set it up in `imconfig.h`.
+- You can use `ImGui::GetBackgroundDrawList()` or `ImGui::GetForegroundDrawList()` to access draw lists which will be displayed behind and over every other Dear ImGui window (one bg/fg drawlist per viewport). This is very convenient if you need to quickly display something on the screen that is not associated with a Dear ImGui window.
+- You can also create your own empty window and draw inside it. Call Begin() with the NoBackground | NoDecoration | NoSavedSettings | NoInputs flags (The `ImGuiWindowFlags_NoDecoration` flag itself is a shortcut for NoTitleBar | NoResize | NoScrollbar | NoCollapse). Then you can retrieve the ImDrawList* via `GetWindowDrawList()` and draw to it in any way you like.
+- You can create your own ImDrawList instance. You'll need to initialize them with `ImGui::GetDrawListSharedData()`, or create your own instancing `ImDrawListSharedData`, and then call your renderer function with your own ImDrawList or ImDrawData data.
+- Looking for fun? The [ImDrawList coding party 2020](https://github.com/ocornut/imgui/issues/3606) thread is full of "don't do this at home" extreme uses of the ImDrawList API.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Fonts, Text
+
+### Q: How should I handle DPI in my application?
+
+The short answer is: obtain the desired DPI scale, load your fonts resized with that scale (always round down fonts size to the nearest integer), and scale your Style structure accordingly using `style.ScaleAllSizes()`.
+
+Your application may want to detect DPI change and reload the fonts and reset style between frames.
+
+Your ui code  should avoid using hardcoded constants for size and positioning. Prefer to express values as multiple of reference values such as `ImGui::GetFontSize()` or `ImGui::GetFrameHeight()`. So e.g. instead of seeing a hardcoded height of 500 for a given item/window, you may want to use `30*ImGui::GetFontSize()` instead.
+
+Down the line Dear ImGui will provide a variety of standardized reference values to facilitate using this.
+
+Applications in the `examples/` folder are not DPI aware partly because they are unable to load a custom font from the file-system (may change that in the future).
+
+The reason DPI is not auto-magically solved in stock examples is that we don't yet have a satisfying solution for the "multi-dpi" problem (using the `docking` branch: when multiple viewport windows are over multiple monitors using different DPI scales). The current way to handle this on the application side is:
+- Create and maintain one font atlas per active DPI scale (e.g. by iterating `platform_io.Monitors[]` before `NewFrame()`).
+- Hook `platform_io.OnChangedViewport()` to detect when a `Begin()` call makes a Dear ImGui window change monitor (and therefore DPI).
+- In the hook: swap atlas, swap style with correctly sized one, and remap the current font from one atlas to the other (you may need to maintain a remapping table of your fonts at varying DPI scales).
+
+This approach is relatively easy and functional but comes with two issues:
+- It's not possibly to reliably size or position a window ahead of `Begin()` without knowing on which monitor it'll land.
+- Style override may be lost during the `Begin()` call crossing monitor boundaries. You may need to do some custom scaling mumbo-jumbo if you want your `OnChangedViewport()` handler to preserve style overrides.
+
+Please note that if you are not using multi-viewports with multi-monitors using different DPI scales, you can ignore that and use the simpler technique recommended at the top.
+
+On Windows, in addition to scaling the font size (make sure to round to an integer) and using `style.ScaleAllSizes()`, you will need to inform Windows that your application is DPI aware. If this is not done, Windows will scale the application window and the UI text will be blurry. Potential solutions to indicate DPI awareness on Windows are:
+
+- For SDL: the flag `SDL_WINDOW_ALLOW_HIGHDPI` needs to be passed to `SDL_CreateWindow()``.
+- For GLFW: this is done automatically.
+- For other Windows projects with other backends, or wrapper projects:
+  - We provide a `ImGui_ImplWin32_EnableDpiAwareness()` helper method in the Win32 backend.
+  - Use an [application manifest file](https://learn.microsoft.com/en-us/windows/win32/hidpi/setting-the-default-dpi-awareness-for-a-process) to set the `<dpiAware>` property.
+
+### Q: How can I load a different font than the default?
+Use the font atlas to load the TTF/OTF file you want:
+
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels);
+io.Fonts->GetTexDataAsRGBA32() or GetTexDataAsAlpha8()
+```
+
+Default is ProggyClean.ttf, monospace, rendered at size 13, embedded in dear imgui's source code.
+
+(Tip: monospace fonts are convenient because they allow to facilitate horizontal alignment directly at the string level.)
+
+(Read the [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) file for more details about font loading.)
+
+New programmers: remember that in C/C++ and most programming languages if you want to use a
+backslash \ within a string literal, you need to write it double backslash "\\":
+
+```cpp
+io.Fonts->AddFontFromFileTTF("MyFolder\MyFont.ttf", size);  // WRONG (you are escaping the M here!)
+io.Fonts->AddFontFromFileTTF("MyFolder\\MyFont.ttf", size); // CORRECT (Windows only)
+io.Fonts->AddFontFromFileTTF("MyFolder/MyFont.ttf", size);  // ALSO CORRECT
+```
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I easily use icons in my application?
+The most convenient and practical way is to merge an icon font such as FontAwesome inside your
+main font. Then you can refer to icons within your strings.
+Read the [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) file for more details about icons font loading.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I load multiple fonts?
+
+Use the font atlas to pack them into a single texture. Read [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) for more details.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display and input non-Latin characters such as Chinese, Japanese, Korean, Cyrillic?
+When loading a font, pass custom Unicode ranges to specify the glyphs to load.
+
+```cpp
+// Add default Japanese ranges
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels, nullptr, io.Fonts->GetGlyphRangesJapanese());
+
+// Or create your own custom ranges (e.g. for a game you can feed your entire game script and only build the characters the game need)
+ImVector<ImWchar> ranges;
+ImFontGlyphRangesBuilder builder;
+builder.AddText("Hello world");                        // Add a string (here "Hello world" contains 7 unique characters)
+builder.AddChar(0x7262);                               // Add a specific character
+builder.AddRanges(io.Fonts->GetGlyphRangesJapanese()); // Add one of the default ranges
+builder.BuildRanges(&ranges);                          // Build the final result (ordered ranges with all the unique characters submitted)
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", 16.0f, nullptr, ranges.Data);
+```
+
+All your strings need to use UTF-8 encoding.
+You need to tell your compiler to use UTF-8, or in C++11 you can encode a string literal in UTF-8 by using the u8"hello" syntax.
+Specifying literal in your source code using a local code page (such as CP-923 for Japanese or CP-1251 for Cyrillic) will NOT work!
+See [About UTF-8 Encoding](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md#about-utf-8-encoding) section
+of [FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) for details about UTF-8 Encoding.
+
+Text input: it is up to your application to pass the right character code by calling `io.AddInputCharacter()`.
+The applications in examples/ are doing that.
+Windows: you can use the WM_CHAR or WM_UNICHAR or WM_IME_CHAR message (depending if your app is built using Unicode or MultiByte mode).
+You may also use `MultiByteToWideChar()` or `ToUnicode()` to retrieve Unicode codepoints from MultiByte characters or keyboard state.
+Windows: if your language is relying on an Input Method Editor (IME), you can write your HWND to ImGui::GetMainViewport()->PlatformHandleRaw
+for the default implementation of GetPlatformIO().Platform_SetImeDataFn() to set your Microsoft IME position correctly.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Concerns
+
+### Q: Who uses Dear ImGui?
+
+You may take a look at:
+
+- [Quotes](https://github.com/ocornut/imgui/wiki/Quotes)
+- [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui)
+- [Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding)
+- [Gallery](https://github.com/ocornut/imgui/issues?q=label%3Agallery)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Can you create elaborate/serious tools with Dear ImGui?
+
+Yes. People have written game editors, data browsers, debuggers, profilers, and all sorts of non-trivial tools with the library. In my experience, the simplicity of the API is very empowering. Your UI runs close to your live data. Make the tools always-on and everybody in the team will be inclined to create new tools (as opposed to more "offline" UI toolkits where only a fraction of your team effectively creates tools). The list of sponsors below is also an indicator that serious game teams have been using the library.
+
+Dear ImGui is very programmer centric and the immediate-mode GUI paradigm might require you to readjust some habits before you can realize its full potential. Dear ImGui is about making things that are simple, efficient, and powerful.
+
+Dear ImGui is built to be efficient and scalable toward the needs for AAA-quality applications running all day. The IMGUI paradigm offers different opportunities for optimization than the more typical RMGUI paradigm.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Can you reskin the look of Dear ImGui?
+
+Somewhat. You can alter the look of the interface to some degree: changing colors, sizes, padding, rounding, and fonts. However, as Dear ImGui is designed and optimized to create debug tools, the amount of skinning you can apply is limited. There is only so much you can stray away from the default look and feel of the interface. Dear ImGui is NOT designed to create a user interface for games, although with ingenious use of the low-level API you can do it.
+
+A reasonably skinned application may look like (screenshot from [#2529](https://github.com/ocornut/imgui/issues/2529#issuecomment-524281119)):
+![minipars](https://user-images.githubusercontent.com/314805/63589441-d9794f00-c5b1-11e9-8d96-cfc1b93702f7.png)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Why using C++ (as opposed to C)?
+
+Dear ImGui takes advantage of a few C++ language features for convenience but nothing anywhere Boost insanity/quagmire. Dear ImGui doesn't use any C++ header file. Dear ImGui uses a very small subset of C++11 features. In particular, function overloading and default parameters are used to make the API easier to use and code terser. Doing so I believe the API is sitting on a sweet spot and giving up on those features would make the API more cumbersome. Other features such as namespace, constructors, and templates (in the case of the ImVector<> class) are also relied on as a convenience.
+
+There is an auto-generated [c-api for Dear ImGui (cimgui)](https://github.com/cimgui/cimgui) by Sonoro1234 and Stephan Dilly. It is designed for creating bindings to other languages. If possible, I would suggest using your target language functionalities to try replicating the function overloading and default parameters used in C++ else the API may be harder to use. Also see [Bindings](https://github.com/ocornut/imgui/wiki/Bindings) for various third-party bindings.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Community
+
+### Q: How can I help?
+- Businesses: please reach out to `omar AT dearimgui.com` if you work in a place using Dear ImGui! We can discuss ways for your company to fund development via invoiced technical support, maintenance, or sponsoring contacts. This is among the most useful thing you can do for Dear ImGui. With increased funding, we can hire more people to work on this project. Please see [Funding](https://github.com/ocornut/imgui/wiki/Funding) page.
+- Individuals: you can support continued maintenance and development via PayPal donations. See [README](https://github.com/ocornut/imgui/blob/master/docs/README.md).
+- If you are experienced with Dear ImGui and C++, look at [GitHub Issues](https://github.com/ocornut/imgui/issues), [GitHub Discussions](https://github.com/ocornut/imgui/discussions), the [Wiki](https://github.com/ocornut/imgui/wiki), read [docs/TODO.txt](https://github.com/ocornut/imgui/blob/master/docs/TODO.txt), and see how you want to help and can help!
+- Disclose your usage of Dear ImGui via a dev blog post, a tweet, a screenshot, a mention somewhere, etc.
+You may post screenshots or links in the [gallery threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery). Visuals are ideal as they inspire other programmers. Disclosing your use of Dear ImGui helps the library grow credibility, and helps other teams and programmers with taking decisions.
+- If you have issues or if you need to hack into the library, even if you don't expect any support it is useful that you share your issues or sometimes incomplete PR.
+
+##### [Return to Index](#index)
+

Source/ThirdParty/ImGuiLibrary/Docs/FONTS.md

@@ -0,0 +1,502 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/FONTS.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Using Fonts
+
+The code in imgui.cpp embeds a copy of 'ProggyClean.ttf' (by Tristan Grimmer),
+a 13 pixels high, pixel-perfect font used by default. We embed it in the source code so you can use Dear ImGui without any file system access. ProggyClean does not scale smoothly, therefore it is recommended that you load your own file when using Dear ImGui in an application aiming to look nice and wanting to support multiple resolutions.
+
+You may also load external .TTF/.OTF files.
+In the [misc/fonts/](https://github.com/ocornut/imgui/tree/master/misc/fonts) folder you can find a few suggested fonts, provided as a convenience.
+
+**Also read the FAQ:** https://www.dearimgui.com/faq (there is a Fonts section!)
+
+## Index
+- [Troubleshooting](#troubleshooting)
+- [How should I handle DPI in my application?](#how-should-i-handle-dpi-in-my-application)
+- [Fonts Loading Instructions](#fonts-loading-instructions)
+- [Loading Font Data from Memory](#loading-font-data-from-memory)
+- [Loading Font Data Embedded In Source Code](#loading-font-data-embedded-in-source-code)
+- [Using Icon Fonts](#using-icon-fonts)
+- [Using FreeType Rasterizer (imgui_freetype)](#using-freetype-rasterizer-imgui_freetype)
+- [Using Colorful Glyphs/Emojis](#using-colorful-glyphsemojis)
+- [Using Custom Glyph Ranges](#using-custom-glyph-ranges)
+- [Using Custom Colorful Icons](#using-custom-colorful-icons)
+- [About Filenames](#about-filenames)
+- [About UTF-8 Encoding](#about-utf-8-encoding)
+- [Debug Tools](#debug-tools)
+- [Credits/Licenses For Fonts Included In Repository](#creditslicenses-for-fonts-included-in-repository)
+- [Font Links](#font-links)
+
+---------------------------------------
+
+## Troubleshooting
+
+**A vast majority of font and text related issues encountered comes from 4 things:**
+
+### (1) Invalid filename due to use of `\` or unexpected working directory.
+
+See [About Filenames](#about-filenames). AddFontXXX functions should assert if the filename is incorrect.
+
+### (2) Invalid UTF-8 encoding of your non-ASCII strings.
+
+See [About UTF-8 Encoding](#about-utf-8-encoding). Use the encoding viewer to confirm encoding of string literal in your source code is correct.
+
+### (3) Missing glyph ranges.
+
+You need to load a font with explicit glyph ranges if you want to use non-ASCII characters. See [Fonts Loading Instructions](#fonts-loading-instructions). Use [Debug Tools](#debug-tools) confirm loaded fonts and loaded glyph ranges.
+
+This is a current constraint of Dear ImGui (which we will lift in the future): when loading a font you need to specify which characters glyphs to load.
+All loaded fonts glyphs are rendered into a single texture atlas ahead of time. Calling either of `io.Fonts->GetTexDataAsAlpha8()`, `io.Fonts->GetTexDataAsRGBA32()` or `io.Fonts->Build()` will build the atlas. This is generally called by the Renderer backend, e.g. `ImGui_ImplDX11_NewFrame()` calls it. **If you use custom glyphs ranges, make sure the array is persistent** and available during the calls to `GetTexDataAsAlpha8()/GetTexDataAsRGBA32()/Build()`.
+
+### (4) Font atlas texture fails to upload to GPU.
+
+This is often of byproduct of point 3. If you have large number of glyphs or multiple fonts, the texture may become too big for your graphics API. **The typical result of failing to upload a texture is if every glyph or everything appears as empty white rectangles.** Mind the fact that some graphics drivers have texture size limitation. If you are building a PC application, mind the fact that your users may use hardware with lower limitations than yours.
+
+![empty squares](https://github.com/user-attachments/assets/68b50fb5-8b9d-4c38-baec-6ac384f06d26)
+
+Some solutions:
+- You may reduce oversampling, e.g. `font_config.OversampleH = 1`, this will half your texture size for a quality loss.
+  Note that while OversampleH = 2 looks visibly very close to 3 in most situations, with OversampleH = 1 the quality drop will be noticeable. Read about oversampling [here](https://github.com/nothings/stb/blob/master/tests/oversample).
+- Reduce glyphs ranges by calculating them from source localization data.
+  You can use the `ImFontGlyphRangesBuilder` for this purpose and rebuilding your atlas between frames when new characters are needed. This will be the biggest win!
+- Set `io.Fonts.Flags |= ImFontAtlasFlags_NoPowerOfTwoHeight;` to disable rounding the texture height to the next power of two.
+- Set `io.Fonts.TexDesiredWidth` to specify a texture width to reduce maximum texture height (see comment in `ImFontAtlas::Build()` function).
+
+Future versions of Dear ImGui should solve this problem.
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## How should I handle DPI in my application?
+
+See [FAQ entry](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md#q-how-should-i-handle-dpi-in-my-application).
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Fonts Loading Instructions
+
+**Load default font:**
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontDefault();
+```
+
+**Load .TTF/.OTF file with:**
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels);
+```
+If you get an assert stating "Could not load font file!", your font filename is likely incorrect. Read [About filenames](#about-filenames) carefully.
+
+**Load multiple fonts:**
+```cpp
+// Init
+ImGuiIO& io = ImGui::GetIO();
+ImFont* font1 = io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels);
+ImFont* font2 = io.Fonts->AddFontFromFileTTF("anotherfont.otf", size_pixels);
+```
+
+In your application loop, select which font to use:
+```cpp
+ImGui::Text("Hello"); // use the default font (which is the first loaded font)
+ImGui::PushFont(font2);
+ImGui::Text("Hello with another font");
+ImGui::PopFont();
+```
+
+**For advanced options create a ImFontConfig structure and pass it to the AddFont() function (it will be copied internally):**
+```cpp
+ImFontConfig config;
+config.OversampleH = 2;
+config.OversampleV = 1;
+config.GlyphExtraSpacing.x = 1.0f;
+ImFont* font = io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, &config);
+```
+
+**Combine multiple fonts into one:**
+```cpp
+// Load a first font
+ImFont* font = io.Fonts->AddFontDefault();
+
+// Add character ranges and merge into the previous font
+// The ranges array is not copied by the AddFont* functions and is used lazily
+// so ensure it is available at the time of building or calling GetTexDataAsRGBA32().
+static const ImWchar icons_ranges[] = { 0xf000, 0xf3ff, 0 }; // Will not be copied by AddFont* so keep in scope.
+ImFontConfig config;
+config.MergeMode = true;
+io.Fonts->AddFontFromFileTTF("DroidSans.ttf", 18.0f, &config, io.Fonts->GetGlyphRangesJapanese()); // Merge into first font
+io.Fonts->AddFontFromFileTTF("fontawesome-webfont.ttf", 18.0f, &config, icons_ranges);             // Merge into first font
+io.Fonts->Build();
+```
+
+**Add a fourth parameter to bake specific font ranges only:**
+
+```cpp
+// Basic Latin, Extended Latin
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesDefault());
+
+// Default + Selection of 2500 Ideographs used by Simplified Chinese
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesChineseSimplifiedCommon());
+
+// Default + Hiragana, Katakana, Half-Width, Selection of 1946 Ideographs
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesJapanese());
+```
+See [Using Custom Glyph Ranges](#using-custom-glyph-ranges) section to create your own ranges.
+
+**Example loading and using a Japanese font:**
+
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("NotoSansCJKjp-Medium.otf", 20.0f, nullptr, io.Fonts->GetGlyphRangesJapanese());
+```
+```cpp
+ImGui::Text(u8"こんにちは！テスト %d", 123);
+if (ImGui::Button(u8"ロード"))
+{
+    // do stuff
+}
+ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+```
+
+![sample code output](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/code_sample_02_jp.png)
+<br>_(settings: Dark style (left), Light style (right) / Font: NotoSansCJKjp-Medium, 20px / Rounding: 5)_
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Loading Font Data from Memory
+
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryTTF(data, data_size, size_pixels, ...);
+```
+
+IMPORTANT: `AddFontFromMemoryTTF()` by default transfer ownership of the data buffer to the font atlas, which will attempt to free it on destruction.
+This was to avoid an unnecessary copy, and is perhaps not a good API (a future version will redesign it).
+If you want to keep ownership of the data and free it yourself, you need to clear the `FontDataOwnedByAtlas` field:
+
+```cpp
+ImFontConfig font_cfg;
+font_cfg.FontDataOwnedByAtlas = false;
+ImFont* font = io.Fonts->AddFontFromMemoryTTF(data, data_size, size_pixels, &font_cfg);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Loading Font Data Embedded In Source Code
+
+- Compile and use [binary_to_compressed_c.cpp](https://github.com/ocornut/imgui/blob/master/misc/fonts/binary_to_compressed_c.cpp) to create a compressed C style array that you can embed in source code.
+- See the documentation in [binary_to_compressed_c.cpp](https://github.com/ocornut/imgui/blob/master/misc/fonts/binary_to_compressed_c.cpp) for instructions on how to use the tool.
+- You may find a precompiled version binary_to_compressed_c.exe for Windows inside the demo binaries package (see [README](https://github.com/ocornut/imgui/blob/master/docs/README.md)).
+- The tool can optionally output Base85 encoding to reduce the size of _source code_ but the read-only arrays in the actual binary will be about 20% bigger.
+
+Then load the font with:
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryCompressedTTF(compressed_data, compressed_data_size, size_pixels, ...);
+```
+or
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryCompressedBase85TTF(compressed_data_base85, size_pixels, ...);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Icon Fonts
+
+Using an icon font (such as [FontAwesome](http://fontawesome.io) or [OpenFontIcons](https://github.com/traverseda/OpenFontIcons)) is an easy and practical way to use icons in your Dear ImGui application.
+A common pattern is to merge the icon font within your main font, so you can embed icons directly from your strings without having to change fonts back and forth.
+
+To refer to the icon UTF-8 codepoints from your C++ code, you may use those headers files created by Juliette Foucaut: https://github.com/juliettef/IconFontCppHeaders.
+
+So you can use `ICON_FA_SEARCH` as a string that will render as a "Search" icon.
+
+Example Setup:
+```cpp
+// Merge icons into default tool font
+#include "IconsFontAwesome.h"
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontDefault();
+
+ImFontConfig config;
+config.MergeMode = true;
+config.GlyphMinAdvanceX = 13.0f; // Use if you want to make the icon monospaced
+static const ImWchar icon_ranges[] = { ICON_MIN_FA, ICON_MAX_FA, 0 };
+io.Fonts->AddFontFromFileTTF("fonts/fontawesome-webfont.ttf", 13.0f, &config, icon_ranges);
+```
+Example Usage:
+```cpp
+// Usage, e.g.
+ImGui::Text("%s among %d items", ICON_FA_SEARCH, count);
+ImGui::Button(ICON_FA_SEARCH " Search");
+// C string _literals_ can be concatenated at compilation time, e.g. "hello" " world"
+// ICON_FA_SEARCH is defined as a string literal so this is the same as "A" "B" becoming "AB"
+```
+See Links below for other icons fonts and related tools.
+
+**Monospace Icons?**
+
+To make your icon look more monospace and facilitate alignment, you may want to set the ImFontConfig::GlyphMinAdvanceX value when loading an icon font.
+
+**Screenshot**
+
+Here's an application using icons ("Avoyd", https://www.avoyd.com):
+![avoyd](https://user-images.githubusercontent.com/8225057/81696852-c15d9e80-9464-11ea-9cab-2a4d4fc84396.jpg)
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using FreeType Rasterizer (imgui_freetype)
+
+- Dear ImGui uses imstb\_truetype.h to rasterize fonts (with optional oversampling). This technique and its implementation are not ideal for fonts rendered at small sizes, which may appear a little blurry or hard to read.
+- There is an implementation of the ImFontAtlas builder using FreeType that you can use in the [misc/freetype/](https://github.com/ocornut/imgui/tree/master/misc/freetype) folder.
+- FreeType supports auto-hinting which tends to improve the readability of small fonts.
+- Read documentation in the [misc/freetype/](https://github.com/ocornut/imgui/tree/master/misc/freetype) folder.
+- Correct sRGB space blending will have an important effect on your font rendering quality.
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Colorful Glyphs/Emojis
+
+- Rendering of colored emojis is supported by imgui_freetype with FreeType 2.10+.
+- You will need to load fonts with the `ImGuiFreeTypeBuilderFlags_LoadColor` flag.
+- Emojis are frequently encoded in upper Unicode layers (character codes >0x10000) and will need dear imgui compiled with `IMGUI_USE_WCHAR32`.
+- Not all types of color fonts are supported by FreeType at the moment.
+- Stateful Unicode features such as skin tone modifiers are not supported by the text renderer.
+
+![colored glyphs](https://user-images.githubusercontent.com/8225057/106171241-9dc4ba80-6191-11eb-8a69-ca1467b206d1.png)
+
+```cpp
+io.Fonts->AddFontFromFileTTF("../../../imgui_dev/data/fonts/NotoSans-Regular.ttf", 16.0f);
+static ImWchar ranges[] = { 0x1, 0x1FFFF, 0 };
+static ImFontConfig cfg;
+cfg.OversampleH = cfg.OversampleV = 1;
+cfg.MergeMode = true;
+cfg.FontBuilderFlags |= ImGuiFreeTypeBuilderFlags_LoadColor;
+io.Fonts->AddFontFromFileTTF("C:\\Windows\\Fonts\\seguiemj.ttf", 16.0f, &cfg, ranges);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Custom Glyph Ranges
+
+You can use the `ImFontGlyphRangesBuilder` helper to create glyph ranges based on text input. For example: for a game where your script is known, if you can feed your entire script to it and only build the characters the game needs.
+```cpp
+ImVector<ImWchar> ranges;
+ImFontGlyphRangesBuilder builder;
+builder.AddText("Hello world");                        // Add a string (here "Hello world" contains 7 unique characters)
+builder.AddChar(0x7262);                               // Add a specific character
+builder.AddRanges(io.Fonts->GetGlyphRangesJapanese()); // Add one of the default ranges
+builder.BuildRanges(&ranges);                          // Build the final result (ordered ranges with all the unique characters submitted)
+
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels, nullptr, ranges.Data);
+io.Fonts->Build();                                     // Build the atlas while 'ranges' is still in scope and not deleted.
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Custom Colorful Icons
+
+As an alternative to rendering colorful glyphs using imgui_freetype with `ImGuiFreeTypeBuilderFlags_LoadColor`, you may allocate your own space in the texture atlas and write yourself into it. **(This is a BETA api, use if you are familiar with dear imgui and with your rendering backend)**
+
+- You can use the `ImFontAtlas::AddCustomRect()` and `ImFontAtlas::AddCustomRectFontGlyph()` api to register rectangles that will be packed into the font atlas texture. Register them before building the atlas, then call Build()`.
+- You can then use `ImFontAtlas::GetCustomRectByIndex(int)` to query the position/size of your rectangle within the texture, and blit/copy any graphics data of your choice into those rectangles.
+- This API is beta because it is likely to change in order to support multi-dpi (multiple viewports on multiple monitors with varying DPI scale).
+
+#### Pseudo-code:
+```cpp
+// Add font, then register two custom 13x13 rectangles mapped to glyph 'a' and 'b' of this font
+ImFont* font = io.Fonts->AddFontDefault();
+int rect_ids[2];
+rect_ids[0] = io.Fonts->AddCustomRectFontGlyph(font, 'a', 13, 13, 13+1);
+rect_ids[1] = io.Fonts->AddCustomRectFontGlyph(font, 'b', 13, 13, 13+1);
+
+// Build atlas
+io.Fonts->Build();
+
+// Retrieve texture in RGBA format
+unsigned char* tex_pixels = nullptr;
+int tex_width, tex_height;
+io.Fonts->GetTexDataAsRGBA32(&tex_pixels, &tex_width, &tex_height);
+
+for (int rect_n = 0; rect_n < IM_ARRAYSIZE(rect_ids); rect_n++)
+{
+    int rect_id = rect_ids[rect_n];
+    if (const ImFontAtlasCustomRect* rect = io.Fonts->GetCustomRectByIndex(rect_id))
+    {
+        // Fill the custom rectangle with red pixels (in reality you would draw/copy your bitmap data here!)
+        for (int y = 0; y < rect->Height; y++)
+        {
+            ImU32* p = (ImU32*)tex_pixels + (rect->Y + y) * tex_width + (rect->X);
+            for (int x = rect->Width; x > 0; x--)
+                *p++ = IM_COL32(255, 0, 0, 255);
+        }
+    }
+}
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## About Filenames
+
+**Please note that many new C/C++ users have issues loading their files _because the filename they provide is wrong_ due to incorrect assumption of what is the current directory.**
+
+Two things to watch for:
+
+(1) In C/C++ and most programming languages if you want to use a backslash `\` within a string literal, you need to write it double backslash `\\`. At it happens, Windows uses backslashes as a path separator, so be mindful.
+```cpp
+io.Fonts->AddFontFromFileTTF("MyFiles\MyImage01.jpg", ...);   // This is INCORRECT!!
+io.Fonts->AddFontFromFileTTF("MyFiles\\MyImage01.jpg", ...);  // This is CORRECT
+```
+In some situations, you may also use `/` path separator under Windows.
+
+(2) Make sure your IDE/debugger settings starts your executable from the right working (current) directory. In Visual Studio you can change your working directory in project `Properties > General > Debugging > Working Directory`. People assume that their execution will start from the root folder of the project, where by default it often starts from the folder where object or executable files are stored.
+```cpp
+io.Fonts->AddFontFromFileTTF("MyImage01.jpg", ...);       // Relative filename depends on your Working Directory when running your program!
+io.Fonts->AddFontFromFileTTF("../MyImage01.jpg", ...);    // Load from the parent folder of your Working Directory
+```
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## About UTF-8 Encoding
+
+**For non-ASCII characters display, a common user issue is not passing correctly UTF-8 encoded strings.**
+
+(1) We provide a function `ImGui::DebugTextEncoding(const char* text)` which you can call to verify the content of your UTF-8 strings.
+This is a convenient way to confirm that your encoding is correct.
+
+```cpp
+ImGui::SeparatorText("CORRECT");
+ImGui::DebugTextEncoding(u8"こんにちは");
+
+ImGui::SeparatorText("INCORRECT");
+ImGui::DebugTextEncoding("こんにちは");
+```
+![UTF-8 Encoding viewer](https://github.com/ocornut/imgui/assets/8225057/61c1696a-9a94-46c5-9627-cf91211111f0)
+
+You can also find this tool under `Metrics/Debuggers->Tools->UTF-8 Encoding viewer` if you want to paste from clipboard, but this won't validate the UTF-8 encoding done by your compiler.
+
+(2) To encode in UTF-8:
+
+There are also compiler-specific ways to enforce UTF-8 encoding by default:
+
+- Visual Studio compiler: `/utf-8` command-line flag.
+- Visual Studio compiler: `#pragma execution_character_set("utf-8")` inside your code.
+- Since May 2023 we have changed the Visual Studio projects of all our examples to use `/utf-8` ([see commit](https://github.com/ocornut/imgui/commit/513af1efc9080857bbd10000d98f98f2a0c96803)).
+
+Or, since C++11, you can use the `u8"my text"` syntax to encode literal strings as UTF-8. e.g.:
+```cpp
+ImGui::Text(u8"hello");
+ImGui::Text(u8"こんにちは");   // this will always be encoded as UTF-8
+ImGui::Text("こんにちは");     // the encoding of this is depending on compiler settings/flags and may be incorrect.
+```
+
+Since C++20, because the C++ committee hate its users, they decided to change the `u8""` syntax to not return `const char*` but a new type `const char8_t*` which doesn't cast to `const char*`.
+Because of type usage of `u8""` in C++20 is a little more tedious:
+```cpp
+ImGui::Text((const char*)u8"こんにちは");
+```
+However, you can disable this behavior completely using the compiler option [`/Zc:char8_t-`](https://learn.microsoft.com/en-us/cpp/build/reference/zc-char8-t?view=msvc-170) for MSVC and [`-fno-char8_t`](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1423r3.html) for Clang and GCC.
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Debug Tools
+
+#### Metrics/Debugger->Fonts
+You can use the `Metrics/Debugger` window (available in `Demo>Tools`) to browse your fonts and understand what's going on if you have an issue. You can also reach it in `Demo->Tools->Style Editor->Fonts`. The same information are also available in the Style Editor under Fonts.
+
+![Fonts debugging](https://user-images.githubusercontent.com/8225057/135429892-0e41ef8d-33c5-4991-bcf6-f997a0bcfd6b.png)
+
+#### UTF-8 Encoding Viewer**
+You can use the `UTF-8 Encoding viewer` in `Metrics/Debugger` to verify the content of your UTF-8 strings. From C/C++ code, you can call `ImGui::DebugTextEncoding("my string");` function to verify that your UTF-8 encoding is correct.
+
+![UTF-8 Encoding viewer](https://user-images.githubusercontent.com/8225057/166505963-8a0d7899-8ee8-4558-abb2-1ae523dc02f9.png)
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Credits/Licenses For Fonts Included In Repository
+
+Some fonts files are available in the `misc/fonts/` folder:
+
+**Roboto-Medium.ttf**, by Christian Robetson
+<br>Apache License 2.0
+<br>https://fonts.google.com/specimen/Roboto
+
+**Cousine-Regular.ttf**, by Steve Matteson
+<br>Digitized data copyright (c) 2010 Google Corporation.
+<br>Licensed under the SIL Open Font License, Version 1.1
+<br>https://fonts.google.com/specimen/Cousine
+
+**DroidSans.ttf**, by Steve Matteson
+<br>Apache License 2.0
+<br>https://www.fontsquirrel.com/fonts/droid-sans
+
+**ProggyClean.ttf**, by Tristan Grimmer
+<br>MIT License
+<br>(recommended loading setting: Size = 13.0, GlyphOffset.y = +1)
+<br>http://www.proggyfonts.net/
+
+**ProggyTiny.ttf**, by Tristan Grimmer
+<br>MIT License
+<br>(recommended loading setting: Size = 10.0, GlyphOffset.y = +1)
+<br>http://www.proggyfonts.net/
+
+**Karla-Regular.ttf**, by Jonathan Pinhorn
+<br>SIL OPEN FONT LICENSE Version 1.1
+
+##### [Return to Index](#index)
+
+## Font Links
+
+#### ICON FONTS
+
+- C/C++ header for icon fonts (#define with code points to use in source code string literals) https://github.com/juliettef/IconFontCppHeaders
+- FontAwesome https://fortawesome.github.io/Font-Awesome
+- OpenFontIcons https://github.com/traverseda/OpenFontIcons
+- Google Icon Fonts https://design.google.com/icons/
+- Kenney Icon Font (Game Controller Icons) https://github.com/nicodinh/kenney-icon-font
+- IcoMoon - Custom Icon font builder https://icomoon.io/app
+
+#### REGULAR FONTS
+
+- Google Noto Fonts (worldwide languages) https://www.google.com/get/noto/
+- Open Sans Fonts https://fonts.google.com/specimen/Open+Sans
+- (Japanese) M+ fonts by Coji Morishita http://mplus-fonts.sourceforge.jp/mplus-outline-fonts/index-en.html
+
+#### MONOSPACE FONTS
+
+Pixel Perfect:
+- Proggy Fonts, by Tristan Grimmer http://www.proggyfonts.net or http://upperboundsinteractive.com/fonts.php
+- Sweet16, Sweet16 Mono, by Martin Sedlak (Latin + Supplemental + Extended A) https://github.com/kmar/Sweet16Font (also include an .inl file to use directly in dear imgui.)
+
+Regular:
+- Google Noto Mono Fonts https://www.google.com/get/noto/
+- Typefaces for source code beautification https://github.com/chrissimpkins/codeface
+- Programmation fonts http://s9w.github.io/font_compare/
+- Inconsolata http://www.levien.com/type/myfonts/inconsolata.html
+- Adobe Source Code Pro: Monospaced font family for ui & coding environments https://github.com/adobe-fonts/source-code-pro
+- Monospace/Fixed Width Programmer's Fonts http://www.lowing.org/fonts/
+
+Or use Arial Unicode or other Unicode fonts provided with Windows for full characters coverage (not sure of their licensing).
+
+##### [Return to Index](#index)

Source/ThirdParty/ImGuiLibrary/Docs/README.md

@@ -0,0 +1,222 @@
+Dear ImGui
+=====
+
+<center><b><i>"Give someone state and they'll have a bug one day, but teach them how to represent state in two separate locations that have to be kept in sync and they'll have bugs for a lifetime."</i></b></center> <a href="https://twitter.com/rygorous/status/1507178315886444544">-ryg</a>
+
+----
+
+[![Build Status](https://github.com/ocornut/imgui/workflows/build/badge.svg)](https://github.com/ocornut/imgui/actions?workflow=build) [![Static Analysis Status](https://github.com/ocornut/imgui/workflows/static-analysis/badge.svg)](https://github.com/ocornut/imgui/actions?workflow=static-analysis) [![Tests Status](https://github.com/ocornut/imgui_test_engine/workflows/tests/badge.svg)](https://github.com/ocornut/imgui_test_engine/actions?workflow=tests)
+
+<sub>(This library is available under a free and permissive license, but needs financial support to sustain its continued improvements. In addition to maintenance and stability there are many desirable features yet to be added. If your company is using Dear ImGui, please consider reaching out.)</sub>
+
+Businesses: support continued development and maintenance via invoiced sponsoring/support contracts:
+<br>&nbsp;&nbsp;_E-mail: contact @ dearimgui dot com_
+<br>Individuals: support continued development and maintenance [here](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=WGHNC6MBFLZ2S). Also see [Funding](https://github.com/ocornut/imgui/wiki/Funding) page.
+
+| [The Pitch](#the-pitch) - [Usage](#usage) - [How it works](#how-it-works) - [Releases & Changelogs](#releases--changelogs) - [Demo](#demo) - [Getting Started & Integration](#getting-started--integration) |
+:----------------------------------------------------------: |
+| [Gallery](#gallery) - [Support, FAQ](#support-frequently-asked-questions-faq) -  [How to help](#how-to-help) - **[Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding)** - [Credits](#credits) - [License](#license) |
+| [Wiki](https://github.com/ocornut/imgui/wiki) - [Extensions](https://github.com/ocornut/imgui/wiki/Useful-Extensions) - [Languages bindings & frameworks backends](https://github.com/ocornut/imgui/wiki/Bindings) - [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) - [User quotes](https://github.com/ocornut/imgui/wiki/Quotes) |
+
+### The Pitch
+
+Dear ImGui is a **bloat-free graphical user interface library for C++**. It outputs optimized vertex buffers that you can render anytime in your 3D-pipeline-enabled application. It is fast, portable, renderer agnostic, and self-contained (no external dependencies).
+
+Dear ImGui is designed to **enable fast iterations** and to **empower programmers** to create **content creation tools and visualization / debug tools** (as opposed to UI for the average end-user). It favors simplicity and productivity toward this goal and lacks certain features commonly found in more high-level libraries. Among other things, full internationalization (right-to-left text, bidirectional text, text shaping etc.) and accessibility features are not supported.
+
+Dear ImGui is particularly suited to integration in game engines (for tooling), real-time 3D applications, fullscreen applications, embedded applications, or any applications on console platforms where operating system features are non-standard.
+
+ - Minimize state synchronization.
+ - Minimize UI-related state storage on user side.
+ - Minimize setup and maintenance.
+ - Easy to use to create dynamic UI which are the reflection of a dynamic data set.
+ - Easy to use to create code-driven and data-driven tools.
+ - Easy to use to create ad hoc short-lived tools and long-lived, more elaborate tools.
+ - Easy to hack and improve.
+ - Portable, minimize dependencies, run on target (consoles, phones, etc.).
+ - Efficient runtime and memory consumption.
+ - Battle-tested, used by [many major actors in the game industry](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui).
+
+### Usage
+
+**The core of Dear ImGui is self-contained within a few platform-agnostic files** which you can easily compile in your application/engine. They are all the files in the root folder of the repository (imgui*.cpp, imgui*.h). **No specific build process is required**. You can add the .cpp files into your existing project.
+
+**Backends for a variety of graphics API and rendering platforms** are provided in the [backends/](https://github.com/ocornut/imgui/tree/master/backends) folder, along with example applications in the [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder. You may also create your own backend. Anywhere where you can render textured triangles, you can render Dear ImGui.
+
+See the [Getting Started & Integration](#getting-started--integration) section of this document for more details.
+
+After Dear ImGui is set up in your application, you can use it from \_anywhere\_ in your program loop:
+```cpp
+ImGui::Text("Hello, world %d", 123);
+if (ImGui::Button("Save"))
+    MySaveFunction();
+ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+```
+![sample code output (dark, segoeui font, freetype)](https://user-images.githubusercontent.com/8225057/191050833-b7ecf528-bfae-4a9f-ac1b-f3d83437a2f4.png)
+![sample code output (light, segoeui font, freetype)](https://user-images.githubusercontent.com/8225057/191050838-8742efd4-504d-4334-a9a2-e756d15bc2ab.png)
+
+```cpp
+// Create a window called "My First Tool", with a menu bar.
+ImGui::Begin("My First Tool", &my_tool_active, ImGuiWindowFlags_MenuBar);
+if (ImGui::BeginMenuBar())
+{
+    if (ImGui::BeginMenu("File"))
+    {
+        if (ImGui::MenuItem("Open..", "Ctrl+O")) { /* Do stuff */ }
+        if (ImGui::MenuItem("Save", "Ctrl+S"))   { /* Do stuff */ }
+        if (ImGui::MenuItem("Close", "Ctrl+W"))  { my_tool_active = false; }
+        ImGui::EndMenu();
+    }
+    ImGui::EndMenuBar();
+}
+
+// Edit a color stored as 4 floats
+ImGui::ColorEdit4("Color", my_color);
+
+// Generate samples and plot them
+float samples[100];
+for (int n = 0; n < 100; n++)
+    samples[n] = sinf(n * 0.2f + ImGui::GetTime() * 1.5f);
+ImGui::PlotLines("Samples", samples, 100);
+
+// Display contents in a scrolling region
+ImGui::TextColored(ImVec4(1,1,0,1), "Important Stuff");
+ImGui::BeginChild("Scrolling");
+for (int n = 0; n < 50; n++)
+    ImGui::Text("%04d: Some text", n);
+ImGui::EndChild();
+ImGui::End();
+```
+![my_first_tool_v188](https://user-images.githubusercontent.com/8225057/191055698-690a5651-458f-4856-b5a9-e8cc95c543e2.gif)
+
+Dear ImGui allows you to **create elaborate tools** as well as very short-lived ones. On the extreme side of short-livedness: using the Edit&Continue (hot code reload) feature of modern compilers you can add a few widgets to tweak variables while your application is running, and remove the code a minute later! Dear ImGui is not just for tweaking values. You can use it to trace a running algorithm by just emitting text commands. You can use it along with your own reflection data to browse your dataset live. You can use it to expose the internals of a subsystem in your engine, to create a logger, an inspection tool, a profiler, a debugger, an entire game-making editor/framework, etc.
+
+### How it works
+
+The IMGUI paradigm through its API tries to minimize superfluous state duplication, state synchronization, and state retention from the user's point of view. It is less error-prone (less code and fewer bugs) than traditional retained-mode interfaces, and lends itself to creating dynamic user interfaces. Check out the Wiki's [About the IMGUI paradigm](https://github.com/ocornut/imgui/wiki#about-the-imgui-paradigm) section for more details.
+
+Dear ImGui outputs vertex buffers and command lists that you can easily render in your application. The number of draw calls and state changes required to render them is fairly small. Because Dear ImGui doesn't know or touch graphics state directly, you can call its functions  anywhere in your code (e.g. in the middle of a running algorithm, or in the middle of your own rendering process). Refer to the sample applications in the examples/ folder for instructions on how to integrate Dear ImGui with your existing codebase.
+
+_A common misunderstanding is to mistake immediate mode GUI for immediate mode rendering, which usually implies hammering your driver/GPU with a bunch of inefficient draw calls and state changes as the GUI functions are called. This is NOT what Dear ImGui does. Dear ImGui outputs vertex buffers and a small list of draw calls batches. It never touches your GPU directly. The draw call batches are decently optimal and you can render them later, in your app or even remotely._
+
+### Releases & Changelogs
+
+See [Releases](https://github.com/ocornut/imgui/releases) page for decorated Changelogs.
+Reading the changelogs is a good way to keep up to date with the things Dear ImGui has to offer, and maybe will give you ideas of some features that you've been ignoring until now!
+
+### Demo
+
+Calling the `ImGui::ShowDemoWindow()` function will create a demo window showcasing a variety of features and examples. The code is always available for reference in `imgui_demo.cpp`. [Here's how the demo looks](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v167/v167-misc.png).
+
+You should be able to build the examples from sources. If you don't, let us know! If you want to have a quick look at some Dear ImGui features, you can download Windows binaries of the demo app here:
+- [imgui-demo-binaries-20240105.zip](https://www.dearimgui.com/binaries/imgui-demo-binaries-20240105.zip) (Windows, 1.90.1 WIP, built 2024/01/05, master) or [older binaries](https://www.dearimgui.com/binaries).
+
+The demo applications are not DPI aware so expect some blurriness on a 4K screen. For DPI awareness in your application, you can load/reload your font at a different scale and scale your style with `style.ScaleAllSizes()` (see [FAQ](https://www.dearimgui.com/faq)).
+
+### Getting Started & Integration
+
+See the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide for details.
+
+On most platforms and when using C++, **you should be able to use a combination of the [imgui_impl_xxxx](https://github.com/ocornut/imgui/tree/master/backends) backends without modification** (e.g. `imgui_impl_win32.cpp` + `imgui_impl_dx11.cpp`). If your engine supports multiple platforms, consider using more imgui_impl_xxxx files instead of rewriting them: this will be less work for you, and you can get Dear ImGui running immediately. You can _later_ decide to rewrite a custom backend using your custom engine functions if you wish so.
+
+Integrating Dear ImGui within your custom engine is a matter of 1) wiring mouse/keyboard/gamepad inputs 2) uploading a texture to your GPU/render engine 3) providing a render function that can bind textures and render textured triangles, which is essentially what Backends are doing. The [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder is populated with applications doing just that: setting up a window and using backends. If you follow the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide it should in theory takes you less than an hour to integrate Dear ImGui.  **Make sure to spend time reading the [FAQ](https://www.dearimgui.com/faq), comments, and the examples applications!**
+
+Officially maintained backends/bindings (in repository):
+- Renderers: DirectX9, DirectX10, DirectX11, DirectX12, Metal, OpenGL/ES/ES2, SDL_Renderer, Vulkan, WebGPU.
+- Platforms: GLFW, SDL2/SDL3, Win32, Glut, OSX, Android.
+- Frameworks: Allegro5, Emscripten.
+
+[Third-party backends/bindings](https://github.com/ocornut/imgui/wiki/Bindings) wiki page:
+- Languages: C, C# and: Beef, ChaiScript, CovScript, Crystal, D, Go, Haskell, Haxe/hxcpp, Java, JavaScript, Julia, Kotlin, Lobster, Lua, Nim, Odin, Pascal, PureBasic, Python, ReaScript, Ruby, Rust, Swift, Zig...
+- Frameworks: AGS/Adventure Game Studio, Amethyst, Blender, bsf, Cinder, Cocos2d-x, Defold, Diligent Engine, Ebiten, Flexium, GML/Game Maker Studio, GLEQ, Godot, GTK3, Irrlicht Engine, JUCE, LÖVE+LUA, Mach Engine, Magnum, Marmalade, Monogame, NanoRT, nCine, Nim Game Lib, Nintendo 3DS/Switch/WiiU (homebrew), Ogre, openFrameworks, OSG/OpenSceneGraph, Orx, Photoshop, px_render, Qt/QtDirect3D, raylib, SFML, Sokol, Unity, Unreal Engine 4/5, UWP, vtk, VulkanHpp, VulkanSceneGraph, Win32 GDI, WxWidgets.
+- Many bindings are auto-generated (by good old [cimgui](https://github.com/cimgui/cimgui) or newer/experimental [dear_bindings](https://github.com/dearimgui/dear_bindings)), you can use their metadata output to generate bindings for other languages.
+
+[Useful Extensions/Widgets](https://github.com/ocornut/imgui/wiki/Useful-Extensions) wiki page:
+- Automation/testing, Text editors, node editors, timeline editors, plotting, software renderers, remote network access, memory editors, gizmos, etc. Notable and well supported extensions include [ImPlot](https://github.com/epezent/implot) and [Dear ImGui Test Engine](https://github.com/ocornut/imgui_test_engine).
+
+Also see [Wiki](https://github.com/ocornut/imgui/wiki) for more links and ideas.
+
+### Gallery
+
+Examples projects using Dear ImGui: [Tracy](https://github.com/wolfpld/tracy) (profiler), [ImHex](https://github.com/WerWolv/ImHex) (hex editor/data analysis), [RemedyBG](https://remedybg.itch.io/remedybg) (debugger) and [hundreds of others](https://github.com/ocornut/imgui/wiki/Software-using-Dear-ImGui).
+
+For more user-submitted screenshots of projects using Dear ImGui, check out the [Gallery Threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery)!
+
+For a list of third-party widgets and extensions, check out the [Useful Extensions/Widgets](https://github.com/ocornut/imgui/wiki/Useful-Extensions) wiki page.
+
+|  |  |
+|--|--|
+| Custom engine [erhe](https://github.com/tksuoran/erhe) (docking branch)<BR>[![erhe](https://user-images.githubusercontent.com/8225057/190203358-6988b846-0686-480e-8663-1311fbd18abd.jpg)](https://user-images.githubusercontent.com/994606/147875067-a848991e-2ad2-4fd3-bf71-4aeb8a547bcf.png) | Custom engine for [Wonder Boy: The Dragon's Trap](http://www.TheDragonsTrap.com) (2017)<BR>[![the dragon's trap](https://user-images.githubusercontent.com/8225057/190203379-57fcb80e-4aec-4fec-959e-17ddd3cd71e5.jpg)](https://cloud.githubusercontent.com/assets/8225057/20628927/33e14cac-b329-11e6-80f6-9524e93b048a.png) |
+| Custom engine (untitled)<BR>[![editor white](https://user-images.githubusercontent.com/8225057/190203393-c5ac9f22-b900-4d1e-bfeb-6027c63e3d92.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/editor_white.png) | Tracy Profiler ([github](https://github.com/wolfpld/tracy))<BR>[![tracy profiler](https://user-images.githubusercontent.com/8225057/190203401-7b595f6e-607c-44d3-97ea-4c2673244dfb.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v176/tracy_profiler.png) |
+
+### Support, Frequently Asked Questions (FAQ)
+
+See: [Frequently Asked Questions (FAQ)](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md) where common questions are answered.
+
+See: [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) and [Wiki](https://github.com/ocornut/imgui/wiki) for many links, references, articles.
+
+See: [Articles about the IMGUI paradigm](https://github.com/ocornut/imgui/wiki#about-the-imgui-paradigm) to read/learn about the Immediate Mode GUI paradigm.
+
+See: [Upcoming Changes](https://github.com/ocornut/imgui/wiki/Upcoming-Changes).
+
+See: [Dear ImGui Test Engine + Test Suite](https://github.com/ocornut/imgui_test_engine) for Automation & Testing.
+
+For the purposes of getting search engines to crawl the wiki, here's a link to the [Crawlable Wiki](https://github-wiki-see.page/m/ocornut/imgui/wiki) (not for humans, [here's why](https://github-wiki-see.page/)).
+
+Getting started? For first-time users having issues compiling/linking/running or issues loading fonts, please use [GitHub Discussions](https://github.com/ocornut/imgui/discussions). For ANY other questions, bug reports, requests, feedback, please post on [GitHub Issues](https://github.com/ocornut/imgui/issues). Please read and fill the New Issue template carefully.
+
+Private support is available for paying business customers (E-mail: _contact @ dearimgui dot com_).
+
+**Which version should I get?**
+
+We occasionally tag [Releases](https://github.com/ocornut/imgui/releases) (with nice releases notes) but it is generally safe and recommended to sync to latest `master` or `docking` branch. The library is fairly stable and regressions tend to be fixed fast when reported. Advanced users may want to use the `docking` branch with [Multi-Viewport](https://github.com/ocornut/imgui/wiki/Multi-Viewports) and [Docking](https://github.com/ocornut/imgui/wiki/Docking) features. This branch is kept in sync with master regularly.
+
+**Who uses Dear ImGui?**
+
+See the [Quotes](https://github.com/ocornut/imgui/wiki/Quotes), [Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding), and [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) Wiki pages for an idea of who is using Dear ImGui. Please add your game/software if you can! Also, see the [Gallery Threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery)!
+
+How to help
+-----------
+
+**How can I help?**
+
+- See [GitHub Forum/Issues](https://github.com/ocornut/imgui/issues).
+- You may help with development and submit pull requests! Please understand that by submitting a PR you are also submitting a request for the maintainer to review your code and then take over its maintenance forever. PR should be crafted both in the interest of the end-users and also to ease the maintainer into understanding and accepting it.
+- See [Help wanted](https://github.com/ocornut/imgui/wiki/Help-Wanted) on the [Wiki](https://github.com/ocornut/imgui/wiki/) for some more ideas.
+- Be a [Funding Supporter](https://github.com/ocornut/imgui/wiki/Funding)! Have your company financially support this project via invoiced sponsors/maintenance or by buying a license for [Dear ImGui Test Engine](https://github.com/ocornut/imgui_test_engine) (please reach out: omar AT dearimgui DOT com).
+
+Sponsors
+--------
+
+Ongoing Dear ImGui development is and has been financially supported by users and private sponsors.
+<BR>Please see the **[detailed list of current and past Dear ImGui funding supporters and sponsors](https://github.com/ocornut/imgui/wiki/Funding)** for details.
+<BR>From November 2014 to December 2019, ongoing development has also been financially supported by its users on Patreon and through individual donations.
+
+**THANK YOU to all past and present supporters for helping to keep this project alive and thriving!**
+
+Dear ImGui is using software and services provided free of charge for open source projects:
+- [PVS-Studio](https://pvs-studio.com/en/pvs-studio/?utm_source=website&utm_medium=github&utm_campaign=open_source) for static analysis (supports C/C++/C#/Java).
+- [GitHub actions](https://github.com/features/actions) for continuous integration systems.
+- [OpenCppCoverage](https://github.com/OpenCppCoverage/OpenCppCoverage) for code coverage analysis.
+
+Credits
+-------
+
+Developed by [Omar Cornut](https://www.miracleworld.net) and every direct or indirect [contributors](https://github.com/ocornut/imgui/graphs/contributors) to the GitHub. The early version of this library was developed with the support of [Media Molecule](https://www.mediamolecule.com) and first used internally on the game [Tearaway](https://tearaway.mediamolecule.com) (PS Vita).
+
+Recurring contributors include Rokas Kupstys [@rokups](https://github.com/rokups) (2020-2022): a good portion of work on automation system and regression tests now available in [Dear ImGui Test Engine](https://github.com/ocornut/imgui_test_engine).
+
+Maintenance/support contracts, sponsoring invoices and other B2B transactions are hosted and handled by [Disco Hello](https://www.discohello.com).
+
+Omar: "I first discovered the IMGUI paradigm at [Q-Games](https://www.q-games.com) where Atman Binstock had dropped his own simple implementation in the codebase, which I spent quite some time improving and thinking about. It turned out that Atman was exposed to the concept directly by working with Casey. When I moved to Media Molecule I rewrote a new library trying to overcome the flaws and limitations of the first one I've worked with. It became this library and since then I have spent an unreasonable amount of time iterating and improving it."
+
+Embeds [ProggyClean.ttf](https://www.proggyfonts.net) font by Tristan Grimmer (MIT license).
+<br>Embeds [stb_textedit.h, stb_truetype.h, stb_rect_pack.h](https://github.com/nothings/stb/) by Sean Barrett (public domain).
+
+Inspiration, feedback, and testing for early versions: Casey Muratori, Atman Binstock, Mikko Mononen, Emmanuel Briney, Stefan Kamoda, Anton Mikhailov, Matt Willis. Also thank you to everyone posting feedback, questions and patches on GitHub.
+
+License
+-------
+
+Dear ImGui is licensed under the MIT License, see [LICENSE.txt](https://github.com/ocornut/imgui/blob/master/LICENSE.txt) for more information.

Source/ThirdParty/ImGuiLibrary/Docs/TODO.txt

@@ -0,0 +1,383 @@
+dear imgui
+ISSUES & TODO LIST
+
+Issue numbers (#) refer to GitHub issues listed at https://github.com/ocornut/imgui/issues/XXXX
+THIS LIST IS NOT WELL MAINTAINED. MOST OF THE WORK HAPPENS ON GITHUB NOWADAYS.
+The list below consist mostly of ideas noted down before they are requested/discussed by users (at which point they usually exist on the github issue tracker).
+It's mostly a bunch of personal notes, probably incomplete. Feel free to query if you have any questions.
+
+ - doc: add a proper documentation system (maybe relying on automation? #435)
+ - doc: checklist app to verify backends/integration of imgui (test inputs, rendering, callback, etc.).
+ - doc/tips: tips of the day: website? applet in imgui_club?
+ 
+ - window: preserve/restore relative focus ordering (persistent or not), and e.g. of multiple reappearing windows (#2304) -> also see docking reference to same #.
+ - window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
+ - window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
+ - window: auto-fit feedback loop when user relies on any dynamic layout (window width multiplier, column) appears weird to end-user. clarify.
+ - window: begin with *p_open == false could return false.
+ - window: get size/pos helpers given names (see discussion in #249)
+ - window: when window is very small, prioritize resize button over close button.
+ - window: double-clicking on title bar to minimize isn't consistent interaction, perhaps move to single-click on left-most collapse icon?
+ - window: expose contents size. (#1045)
+ - window: using SetWindowPos() inside Begin() and moving the window with the mouse reacts a very ugly glitch. We should just defer the SetWindowPos() call.
+ - window: GetWindowSize() returns (0,0) when not calculated? (#1045)
+ - window: investigate better auto-positioning for new windows.
+ - window: top most window flag? more z-order contrl? (#2574)
+ - window/size: manually triggered auto-fit (double-click on grip) shouldn't resize window down to viewport size?
+ - window/size: how to allow to e.g. auto-size vertically to fit contents, but be horizontally resizable? Assuming SetNextWindowSize() is modified to treat -1.0f on each axis as "keep as-is" (would be good but might break erroneous code): Problem is UpdateWindowManualResize() and lots of code treat (window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0) together.
+ - window/opt: freeze window flag: if not focused/hovered, return false, render with previous ImDrawList. and/or reduce refresh rate. -> this may require enforcing that it is illegal to submit contents if Begin returns false.
+ - window/child: background options for child windows, border option (disable rounding).
+ - window/child: allow resizing of child windows (possibly given min/max for each axis?.)
+ - window/child: allow SetNextWindowContentSize() to work on child windows.
+ - window/clipping: some form of clipping when DisplaySize (or corresponding viewport) is zero.
+ - window/tabbing: add a way to signify that a window or docked window requires attention (e.g. blinking title bar, trying to click behind a modal).
+ - window/id_stack: add e.g. window->GetIDFromPath() with support for leading / and ../ (#1390, #331) -> model from test engine.
+ ! scrolling: exposing horizontal scrolling with Shift+Wheel even when scrollbar is disabled expose lots of issues (#2424, #1463)
+ - scrolling: while holding down a scrollbar, try to keep the same contents visible (at least while not moving mouse)
+ - scrolling: allow immediately effective change of scroll after Begin() if we haven't appended items yet.
+ - scrolling: forward mouse wheel scrolling to parent window when at the edge of scrolling limits? (useful for listbox,tables?)
+ - scrolling/style: shadows on scrollable areas to denote that there is more contents (see e.g. DaVinci Resolve ui)
+
+ - drawdata: make it easy to deep-copy (or swap?) a full ImDrawData so user can easily save that data if they use threaded rendering. (#1860 see ImDrawDataSnapshot)
+ ! drawlist: add CalcTextSize() func to facilitate consistent code from user pov (currently need to use ImGui or ImFont alternatives!)
+ - drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command). (WIP branch)
+ - drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
+ - drawlist: non-AA strokes have gaps between points (#593, #288), glitch especially on RenderCheckmark() and ColorPicker4().
+ - drawlist: callback: add an extra void* in ImDrawCallback to expose render state instead of pulling from Renderer_RenderState (would break API).
+ - drawlist: AddRect vs AddLine position confusing (#2441)
+ - drawlist/opt: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding. (#1962)
+ - drawlist/opt: AddRect() axis aligned pixel aligned (no-aa) could use 8 triangles instead of 16 and no normal calculation.
+ - drawlist/opt: thick AA line could be doable in same number of triangles as 1.0 AA line by storing gradient+full color in atlas.
+
+ - items: IsItemHovered() info stored in a stack? so that 'if TreeNode() { Text; TreePop; } if IsHovered' return the hover state of the TreeNode?
+
+ - widgets: display mode: widget-label, label-widget (aligned on column or using fixed size), label-newline-tab-widget etc. (#395)
+ - widgets: clean up widgets internal toward exposing everything and stabilizing imgui_internals.h.
+ - widgets: add always-allow-overlap mode. This should perhaps be the default? one problem is that highlight after mouse-wheel scrolling gets deferred, makes scrolling more flickery.
+ - widgets: start exposing PushItemFlag() and ImGuiItemFlags
+ - widgets: alignment options in style (e.g. center Selectable, Right-Align within Button, etc.) #1260
+ - widgets: activate by identifier (trigger button, focus given id)
+ - widgets: custom glyph/shapes replacements for stock sapes. (also #6090 #2431 #2235 #6517)
+ - widgets: coloredit: keep reporting as active when picker is on?
+ - widgets: group/scalarn functions: expose more per-component information. e.g. store NextItemData.ComponentIdx set by scalarn function, groups can expose them back somehow.
+ - selectable: using (size.x == 0.0f) and (SelectableTextAlign.x > 0.0f) followed by SameLine() is currently not supported.
+ - selectable: generic BeginSelectable()/EndSelectable() mechanism. (work out alongside range-select branch)
+ - selectable: a way to visualize partial/mixed selection (e.g. parent tree node has children with mixed selection)
+
+ - input text: preserve scrolling when unfocused?
+ - input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
+ - input text: expose CursorPos in char filter event (#816)
+ - input text: try usage idiom of using InputText with data only exposed through get/set accessors, without extraneous copy/alloc. (#3009)
+ - input text: access public fields via a non-callback API e.g. InputTextGetState("xxx") that may return nullptr if not active (available in internals)
+ - input text: flag to disable live update of the user buffer (also applies to float/int text input) (#701)
+ - input text: hover tooltip could show unclamped text
+ - input text: support for INSERT key to toggle overwrite mode. currently disabled because stb_textedit behavior is unsatisfactory on multi-line. (#2863)
+ - input text: option to Tab after an Enter validation.
+ - input text: add ImGuiInputTextFlags_EnterToApply? (off #218)
+ - input text: easier ways to update buffer (from source char*) while owned. preserve some sort of cursor position for multi-line text.
+ - input text: add discard flag (e.g. ImGuiInputTextFlags_DiscardActiveBuffer) or make it easier to clear active focus for text replacement during edition (#725)
+ - input text: display bug when clicking a drag/slider after an input text in a different window has all-selected text (order dependent). actually a very old bug but no one appears to have noticed it.
+ - input text: allow centering/positioning text so that ctrl+clicking Drag or Slider keeps the textual value at the same pixel position.
+ - input text: decorrelate display layout from inputs with custom template - e.g. what's the easiest way to implement a nice IP/Mac address input editor?
+ - input text: global callback system so user can plug in an expression evaluator easily. (#1691)
+ - input text: force scroll to end or scroll to a given line/contents (so user can implement a log or a search feature)
+ - input text: a way to preview completion (e.g. disabled text completing from the cursor)
+ - input text: a side bar that could e.g. preview where errors are. probably left to the user to draw but we'd need to give them the info there.
+ - input text: a way for the user to provide syntax coloring.
+ - input text: Shift+TAB with ImGuiInputTextFlags_AllowTabInput could eat preceding blanks, up to tab_count.
+ - input text multi-line: don't directly call AddText() which does an unnecessary vertex reserve for character count prior to clipping. and/or more line-based clipping to AddText(). and/or reorganize TextUnformatted/RenderText for more efficiency for large text (e.g TextUnformatted could clip and log separately, etc).
+ - input text multi-line: support for copy/cut without selection (copy/cut current line?)
+ - input text multi-line: line numbers? status bar? (follow up on #200)
+ - input text multi-line: behave better when user changes input buffer while editing is active (even though it is illegal behavior). namely, the change of buffer can create a scrollbar glitch (#725)
+ - input text multi-line: better horizontal scrolling support (#383, #1224)
+ - input text multi-line: single call to AddText() should be coarse clipped on InputTextEx() end.
+ - input number: optional range min/max for Input*() functions
+ - input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
+ - input number: use mouse wheel to step up/down
+
+ - layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
+ - layout, font: horizontal tab support, A) text mode: forward only tabs (e.g. every 4 characters/N pixels from pos x1), B) manual mode: explicit tab stops acting as mini columns, no clipping (for menu items, many kind of uses, also vaguely relate to #267, #395)
+ - layout: horizontal layout helper (#97)
+ - layout: horizontal flow until no space left (#404)
+ - layout: more generic alignment state (left/right/centered) for single items?
+ - layout: clean up the InputFloatN/SliderFloatN/ColorEdit4 layout code. item width should include frame padding.
+ - layout: vertical alignment of mixed height items (e.g. buttons) within a same line (#1284)
+ - layout: null layout mode were items are not rendered but user can query GetItemRectMin()/Max/Size.
+ - layout: (R&D) local multi-pass layout mode.
+ - layout: (R&D) bind authored layout data (created by an off-line tool), items fetch their pos/size at submission, self-optimize data structures to stable linear access.
+
+ - tables: see https://github.com/ocornut/imgui/issues/2957#issuecomment-569726095
+
+ - group: BeginGroup() needs a border option. (~#1496)
+ - group: IsItemHovered() after EndGroup() covers whole AABB rather than the intersection of individual items. Is that desirable?
+ - group: merge deactivation/activation within same group (fwd WasEdited flag). (#2550)
+
+!- color: the color conversion helpers/types are a mess and needs sorting out.
+ - color: (api breaking) ImGui::ColorConvertXXX functions should be loose ImColorConvertXX to match imgui_internals.h
+
+ - plot: full featured plot/graph api w/ scrolling, zooming etc. --> promote using ImPlot
+ - (plot: deleted all other todo lines on 2023-06-28)
+
+ - clipper: ability to disable the clipping through a simple flag/bool.
+ - clipper: ability to run without knowing full count in advance.
+ - clipper: horizontal clipping support. (#2580)
+
+ - separator: expose flags (#759)
+ - separator: take indent into consideration (optional)
+ - separator: width, thickness, centering (#1643, #2657)
+ - splitter: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)
+
+ - docking: B: ordering currently held in tab bar should be implicitly held by windows themselves (also see #2304)
+ - docking: B- tab bar: the order/focus restoring code could be part of TabBar and not DockNode? (#8)
+ - docking: B~ rework code to be able to lazily create tab bar instance in a single place. The _Unsorted tab flag could be replacing a trailing-counter in DockNode?
+ - docking: B~ fully track windows/settings reference in dock nodes. perhaps find a representation that allows facilitate use of dock builder functions.
+ - docking: B~ Unreal style document system (requires low-level controls of dockspace serialization fork/copy/delete). this is mostly working but the DockBuilderXXX api are not exposed/finished.
+ - docking: B: when docking outer, perform size locking on neighbors nodes the same way we do it with splitters, so other nodes are not resized.
+ - docking: B~ central node resizing behavior incorrect.
+ - docking: B: changing title font/style per-window is not supported as dock nodes are created in NewFrame.
+ - docking: B- dock node inside its own viewports creates 1 temporary viewport per window on startup before ditching them (doesn't affect the user nor request platform windows to be created, but unnecessary)
+ - docking: B- resize sibling locking behavior may be less desirable if we merged same-axis sibling in a same node level?
+ - docking: B- single visible node part of a hidden split hierarchy (OnlyNodeWithWindows != NULL) should show a normal title bar (not a tab bar)
+ - docking: B~ SetNextWindowDock() calls (with conditional) -> defer everything to DockContextUpdate (repro: Documents->[X]Windows->Dock 1 elsewhere->Click Redock All
+ - docking: B~ tidy up tab list popup buttons features (available with manual tab-bar, see ImGuiTabBarFlags_NoTabListPopupButton code, not used by docking nodes)
+ - docking: B- SetNextWindowDockId(0) with a second Begin() in the frame will asserts
+ - docking: B: resize grip drawn in host window typically appears under scrollbar.
+ - docking: B: resize grip auto-resize on multiple node hierarchy doesn't make much sense or should be improved?
+ - docking: B- SetNextWindowFocus() doesn't seem to apply if the window is hidden this frame, need repro (#4)
+ - docking: B- resizing a dock tree small currently has glitches (overlapping collapse and close button, etc.)
+ - docking: B- dpi: look at interaction with the hi-dpi and multi-dpi stuff.
+ - docking: B- tab bar: appearing on first frame with a dumb layout would do less harm that not appearing? (when behind dynamic branch) or store titles + render in EndTabBar()
+ - docking: B- tab bar: make selected tab always shows its full title?
+ - docking: B- hide close button on single tab bar?
+ - docking: B- nav: design interactions so nav controls can dock/undock
+ - docking: B- dockspace: flag to lock the dock tree and/or sizes (ImGuiDockNodeFlags_Locked?)
+ - docking: B- reintroduce collapsing a floating dock node. also collapsing a docked dock node!
+ - docking: B- allow dragging a non-floating dock node by clicking on the title-bar-looking section (not just the collapse/menu button)
+ - docking: B- option to remember undocked window size? (instead of keeping their docked size) (relate to #2104)
+ - docking: C- nav: CTRL+TAB highlighting tabs shows the mismatch between focus-stack and tab-order (not visible in VS because it doesn't highlight the tabs)
+ - docking: C- after a dock/undock, the Scrollbar Status update in Begin() should use an updated e.g. size_y_for_scrollbars to avoid a 1 frame scrollbar flicker.
+
+ - tabs: "there is currently a problem because TabItem() will try to submit their own tooltip after 0.50 second, and this will have the effect of making your tooltip flicker once." -> tooltip priority work (WIP branch)
+ - tabs: make EndTabBar fail if users doesn't respect BeginTabBar return value, for consistency/future-proofing.
+ - tabs: persistent order/focus in BeginTabBar() api (#261, #351)
+ - tabs: explicit api (even if internal) to cleanly manipulate tab order.
+
+ - image/image button: misalignment on padded/bordered button?
+ - image/image button: parameters are confusing, image() has tint_col,border_col whereas imagebutton() has bg_col/tint_col. Even thou they are different parameters ordering could be more consistent. can we fix that?
+ - slider: allow using the [-]/[+] buttons used by InputFloat()/InputInt()
+ - slider: add dragging-based widgets to edit values with mouse (on 2 axises), saving screen real-estate.
+ - slider: tint background based on value (e.g. v_min -> v_max, or use 0.0f either side of the sign)
+ - slider: relative dragging? + precision dragging
+ - slider: step option (#1183)
+ - slider: style: fill % of the bar instead of positioning a drag.
+ - knob: rotating knob widget (#942)
+ - drag float: support for reversed drags (min > max) (removed is_locked, also see fdc526e)
+ - drag float: up/down axis
+ - drag float: power != 0.0f with current value being outside the range keeps the value stuck.
+ - drag float: added leeway on edge (e.g. a few invisible steps past the clamp limits)
+
+ - combo: a way/helper to customize the combo preview (#1658) -> experimental BeginComboPreview()
+ - combo/listbox: keyboard control. need InputText-like non-active focus + key handling. considering keyboard for custom listbox (pr #203)
+ - listbox: multiple selection (WIP range-select branch)
+ - listbox: unselect option (#1208)
+ - listbox: make it easier/more natural to implement range-select (need some sort of info/ref about the last clicked/focused item that user can translate to an index?) (WIP range-select branch)
+ - listbox: user may want to initial scroll to focus on the one selected value?
+ - listbox: disable capturing mouse wheel if the listbox has no scrolling. (#1681)
+ - listbox: scrolling should track modified selection.
+ - listbox: future api should allow to enable horizontal scrolling (#2510)
+
+!- popups/menus: clarify usage of popups id, how MenuItem/Selectable closing parent popups affects the ID, etc. this is quite fishy needs improvement! (#331, #402)
+ - modals: make modal title bar blink when trying to click outside the modal
+ - modals: technically speaking, we could make Begin() with ImGuiWindowFlags_Modal work without involving popup. May help untangle a few things, as modals are more like regular windows than popups.
+ - popups: if the popup functions took explicit ImGuiID it would allow the user to manage the scope of those ID. (#331)
+ - popups: clicking outside (to close popup) and holding shouldn't drag window below.
+ - popups: add variant using global identifier similar to Begin/End (#402)
+ - popups: border options. richer api like BeginChild() perhaps? (#197)
+ - popups/modals: although it is sometimes convenient that popups/modals lifetime is owned by imgui, we could also a bool-owned-by-user api as long as Begin() return value testing is enforced.
+
+ - tooltip: drag and drop with tooltip near monitor edges lose/changes its last direction instead of locking one. The drag and drop tooltip should always follow without changing direction.
+ - tooltip: allow to set the width of a tooltip to allow TextWrapped() etc. while keeping the height automatic.
+ - tooltip: drag tooltip hovering over source widget with IsItemHovered/SetTooltip flickers (WIP branch)
+ - tooltip: tooltip priorities to override a stock tooltip (e.g. shortcut tooltip)
+
+ - status-bar: add a per-window status bar helper similar to what menu-bar does. generalize concept of layer0 rect in window (can make _MenuBar window flag obsolete too).
+ - shortcuts: store multiple keychords in ImGuiKeyChord
+ - shortcuts: Hovered route (lower than Focused, higher than Global)
+ - shortcuts: local-style shortcut api, e.g. parse "&Save"
+ - shortcuts,menus: global-style shortcut api e.g. "Save (CTRL+S)" -> explicit flag for recursing into closed menu
+ - menus: hovering from menu to menu on a menu-bar has 1 frame without any menu, which is a little annoying. ideally zero.
+ - menus: would be nice if the Selectable() supported horizontal alignment (must be given the equivalent of WorkRect.Max.x matching the position of the shortcut column)
+
+ - tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
+ - tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?
+ - tree node / selectable render mismatch which is visible if you use them both next to each other (e.g. cf. property viewer)
+ - tree node: tweak color scheme to distinguish headers from selected tree node (#581)
+ - tree node: leaf/non-leaf highlight mismatch.
+ - tree node/opt: could avoid formatting when clipped (flag assuming we don't care about width/height, assume single line height? format only %s/%c to be able to count height?)
+
+ - settings: write more decent code to allow saving/loading new fields: columns, selected tree nodes?
+ - settings: facilitate extension lazily calling AddSettingsHandler() while running and still getting their data call the ReadXXX handlers immediately.
+ - settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
+ - settings/persistence: helpers to make TreeNodeBehavior persist (even during dev!) - may need to store some semantic and/or data type in ImGuiStoragePair
+
+ - style: better default styles. (#707)
+ - style: add a highlighted text color (for headers, etc.)
+ - style: border types: out-screen, in-screen, etc. (#447)
+ - style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
+ - style: a concept of "compact style" that the end-user can easily rely on (e.g. PushStyleCompact()?) that maps to other settings? avoid implementing duplicate helpers such as SmallCheckbox(), etc.
+ - style: try to make PushStyleVar() more robust to incorrect parameters (to be more friendly to edit & continues situation).
+ - style: global scale setting.
+ - style: FramePadding could be different for up vs down (#584)
+ - style: WindowPadding needs to be EVEN as the 0.5 multiplier used on this value probably have a subtle effect on clip rectangle
+ - style: have a more global HSV setter (e.g. alter hue on all elements). consider replacing active/hovered by offset in HSV space? (#438, #707, #1223)
+ - style: gradients fill (#1223) ~ 2 bg colors for each fill? tricky with rounded shapes and using textures for corners.
+ - style editor: color child window height expressed in multiple of line height.
+
+ - log: improve logging of ArrowButton, ListBox, TabItem
+ - log: carry on indent / tree depth when opening a child window
+ - log: enabling log ends up pushing and growing vertices buffers because we don't distinguish layout vs render clipping
+ - log: have more control over the log scope (e.g. stop logging when leaving current tree node scope)
+ - log: be able to log anything (e.g. right-click on a window/tree-node, shows context menu? log into tty/file/clipboard)
+ - log: let user copy any window content to clipboard easily (CTRL+C on windows? while moving it? context menu?). code is commented because it fails with multiple Begin/End pairs.
+ - log: obsolete LogButtons().... (was: LogButtons() options for specifying depth and/or hiding depth slider)
+
+ - filters: set a current filter that certains items (e.g. tree node) can automatically query to hide themselves
+ - filters: handle wild-cards (with implicit leading/trailing *), reg-exprs
+ - filters: fuzzy matches (may use code at blog.forrestthewoods.com/4cffeed33fdb)
+
+ - drag and drop: focus drag target window on hold (even without open)
+ - drag and drop: releasing a drop shows the "..." tooltip for one frame - since e13e598 (#1725)
+ - drag and drop: drag source on a group object (would need e.g. an invisible button covering group in EndGroup) https://twitter.com/paniq/status/1121446364909535233
+ - drag and drop: have some way to know when a drag begin from BeginDragDropSource() pov. (see 2018/01/11 post in #143)
+ - drag and drop: allow preview tooltip to be submitted from a different place than the drag source. (#1725)
+ - drag and drop: make it easier and provide a demo to have tooltip both are source and target site, with a more detailed one on target site (tooltip ordering problem)
+ - drag and drop: demo with reordering nodes (in a list, or a tree node). (#143)
+ - drag and drop: test integrating with os drag and drop (make it easy to do a naive WM_DROPFILE integration)
+ - drag and drop: allow for multiple payload types. (#143)
+ - drag and drop: make payload optional? payload promise? (see 2018/01/11 post in #143)
+ - drag and drop: (#143) "both an in-process pointer and a promise to generate a serialized version, for whether the drag ends inside or outside the same process"
+ - drag and drop: feedback when hovering a region blocked by modal (mouse cursor "NO"?)
+
+ - markup: simple markup language for color change? (#902, #3130)
+
+ - text: selectable text (for copy) as a generic feature (ItemFlags?)
+ - text: proper alignment options in imgui_internal.h
+ - text: provided a framed text helper, e.g. https://pastebin.com/1Laxy8bT
+ - text: refactor TextUnformatted (or underlying function) to more explicitly request if we need width measurement or not
+ - text/layout/tabs: \t pulling position from base pos + step, or offset array (e.g. could be used in text edit, menus for simple icon+text alignment, etc.)
+ - text link/url button: underlined. should api expose an ID or use text contents as ID? which colors enum to use?
+ - text/wrapped: should be a more first-class citizen, e.g. wrapped text within a Selectable with known width.
+ - text/wrapped: custom separator for text wrapping. (#3002)
+ - text/wrapped: figure out better way to use TextWrapped() in an always auto-resize context (tooltip, etc.) (#249)
+
+ - font: arbitrary line spacing. (#2945)
+ - font: MergeMode: flags to select overwriting or not (this is now very easy with refactored ImFontAtlasBuildWithStbTruetype)
+ - font: free the Alpha buffer if user only requested RGBA.
+!- font: better CalcTextSizeA() API, at least for simple use cases. current one is horrible (perhaps have simple vs extended versions).
+ - font: for the purpose of RenderTextEllipsis(), it might be useful that CalcTextSizeA() can ignore the trailing padding?
+ - font: a CalcTextHeight() helper could run faster than CalcTextSize().y
+ - font: enforce monospace through ImFontConfig (for icons?) + create dual ImFont output from same input, reusing rasterized data but with different glyphs/AdvanceX
+ - font: finish CustomRectRegister() to allow mapping Unicode codepoint to custom texture data
+ - font: remove ID from CustomRect registration, it seems unnecessary!
+ - font: make it easier to submit own bitmap font (same texture, another texture?). (#2127, #2575)
+ - font: PushFontSize API (#1018)
+ - font: MemoryTTF taking ownership confusing/not obvious, maybe default should be opposite?
+ - font: storing MinAdvanceX per font would allow us to skip calculating line width (under a threshold of character count) in loops looking for block width
+ - font/demo: add tools to show glyphs used by a text blob, display U16 value, list missing glyphs.
+ - font/demo: demonstrate use of ImFontGlyphRangesBuilder.
+ - font/atlas: add a missing Glyphs.reserve()
+ - font/atlas: incremental updates
+ - font/atlas: dynamic font atlas to avoid baking huge ranges into bitmap and make scaling easier.
+ - font/draw: vertical and/or rotated text renderer (#705) - vertical is easier clipping wise
+ - font/draw: need to be able to specify wrap start position.
+ - font/draw: better reserve policy for large horizontal block of text (shouldn't reserve for all clipped lines). also see #3349.
+ - font/draw: fix for drawing 16k+ visible characters in same call.
+ - font/draw: underline, squiggle line rendering helpers.
+ - font: optimization: for monospace font (like the default one) we can trim IndexXAdvance as long as trailing value is == FallbackXAdvance (need to make sure TAB is still correct), would save on cache line.
+ - font: add support for kerning, probably optional. A) perhaps default to (32..128)^2 matrix ~ 9K entries = 36KB, then hash for non-ascii?. B) or sparse lookup into per-char list?
+ - font: add a simpler CalcTextSizeA() api? current one ok but not welcome if user needs to call it directly (without going through ImGui::CalcTextSize)
+ - font: fix AddRemapChar() to work before atlas  has been built.
+ - font: (api breaking) remove "TTF" from symbol names. also because it now supports OTF.
+ - font/opt: Considering storing standalone AdvanceX table as 16-bit fixed point integer?
+ - font/opt: Glyph currently 40 bytes (2+9*4). Consider storing UV as 16-bits integer? (->32 bytes). X0/Y0/X1/Y1 as 16 fixed-point integers? Or X0/Y0 as float and X1/Y1 as fixed8_8?
+
+ - nav: some features such as PageUp/Down/Home/End should probably work without ImGuiConfigFlags_NavEnableKeyboard? (where do we draw the line? how about CTRL+Tab)
+ - nav: Home/End behavior when navigable item is not fully visible at the edge of scrolling? should be backtrack to keep item into view?
+ - nav: NavScrollToBringItemIntoView() with item bigger than view should focus top-right? Repro: using Nav in "About Window"
+ - nav: expose wrap around flags/logic to allow e.g. grid based layout (pressing NavRight on the right-most element would go to the next row, etc.). see internal's NavMoveRequestTryWrapping().
+ - nav: patterns to make it possible for arrows key to update selection (see JustMovedTo in range_select branch)
+ - nav: restore/find nearest NavId when current one disappear (e.g. pressed a button that disappear, or perhaps auto restoring when current button change name)
+ - nav: SetItemDefaultFocus() level of priority, so widget like Selectable when inside a popup could claim a low-priority default focus on the first selected iem
+ - nav: holding space to repeat a button doesn't show button activated during hold.
+ - nav: NavFlattened: init requests don't work properly on flattened siblings.
+ - nav: NavFlattened: pageup/pagedown/home/end don't work properly on flattened siblings.
+ - nav: NavFlattened: ESC on a flattened child should select something.
+ - nav: NavFlattened: broken: in typical usage scenario, the items of a fully clipped child are currently not considered to enter into a NavFlattened child.
+ - nav: NavFlattened: cannot access menu-bar of a flattened child window with Alt/menu key (not a very common use case..).
+ - nav: simulate right-click or context activation? (SHIFT+F10, keyboard Menu key?)
+ - nav/popup: esc/enter default behavior for popups, e.g. be able to mark an "ok" or "cancel" button that would get triggered by those keys, default validation button, etc.
+ - nav/treenode: left within a tree node block as a fallback (ImGuiTreeNodeFlags_NavLeftJumpsBackHere by default?)
+ - nav/menus: pressing left-right on a vertically clipped menu bar tends to jump to the collapse/close buttons.
+ - nav/menus: allow pressing Menu to leave a sub-menu.
+ - nav/menus: a way to access the main menu bar with Alt? (currently needs CTRL+TAB) or last focused window menu bar?
+ - nav/menus: when using the main menu bar, even though we restore focus after, the underlying window loses its title bar highlight during menu manipulation. could we prevent it?
+ - nav/menus: main menu bar currently cannot restore a nullptr focus. Could save NavWindow at the time of being focused, similarly to what popup do?
+ - nav/menus: Alt,Up could open the first menu (e.g. "File") currently it tends to nav into the window/collapse menu. Do do that we would need custom transition?
+ - nav/windowing: when CTRL+Tab/windowing is active, the HoveredWindow detection doesn't take account of the window display re-ordering.
+ - nav/windowing: Resizing window will currently fail with certain types of resizing constraints/callback applied
+ - focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
+
+ - viewport: make it possible to have no main/hosting viewport
+ - viewport: We set ImGuiViewportFlags_NoFocusOnAppearing in a way that is required for GLFW/SDL binding, but could be handled better without
+   on a custom e.g. Win32 bindings. It prevents newly dragged-out viewports from taking the focus, which makes ALT+F4 more ambiguous.
+ - viewport: not focusing newly undocked viewport means clicking back on previous one doesn't bring OS window to front.
+ - viewport: with platform decoration enabled, platform may force constraint (e.g. minimum size)
+ - viewport: use getfocus/setfocus api to synchronize imgui<>platform focus better (e.g imgui-side ctrl-tab can focus os window, OS initial setup and alt-tab can focus imgui window etc.)
+ - viewport: store per-viewport/monitor DPI in .ini file so an application reload or main window changing DPI on reload can be properly patched for.
+ - viewport: implicit/fallback Debug window can hog a zombie viewport (harmless, noisy?) > could at least clear out the reference on a per session basis?
+ - viewport: need to clarify how to use GetMousePos() from a user point of view.
+ - platform: glfw: no support for ImGuiBackendFlags_HasMouseHoveredViewport.
+ - platform: sdl: no support for ImGuiBackendFlags_HasMouseHoveredViewport. maybe we could use SDL_GetMouseFocus() / SDL_WINDOW_MOUSE_FOCUS if imgui could fallback on its heuristic when NoInputs is set
+ - platform: sdl: no refresh of monitor/display (SDL doesn't seem to have an event for it).
+ - platform: sdl: multi-viewport + minimized window seems to break mouse wheel events (at least under Win32).
+
+ - inputs: support track pad style scrolling & slider edit.
+ - inputs/io: backspace and arrows in the context of a text input could use system repeat rate.
+ - inputs/io: clarify/standardize/expose repeat rate and repeat delays (#1808)
+ - inputs/scrolling: support for smooth scrolling (#2462, #2569)
+
+ - misc: idle: expose "woken up" boolean (set by inputs) and/or animation time (for cursor blink) for backend to be able stop refreshing easily.
+ - misc: idle: if cursor blink if the _only_ visible animation, core imgui could rewrite vertex alpha to avoid CPU pass on ImGui:: calls.
+ - misc: idle: if cursor blink if the _only_ visible animation, could even expose a dirty rectangle that optionally can be leverage by some app to render in a smaller viewport, getting rid of much pixel shading cost.
+ - misc: no way to run a root-most GetID() with ImGui:: api since there's always a Debug window in the stack. (mentioned in #2960)
+ - misc: make the ImGuiCond values linear (non-power-of-two). internal storage for ImGuiWindow can use integers to combine into flags (Why?)
+ - misc: PushItemFlag(): add a flag to disable keyboard capture when used with mouse? (#1682)
+ - misc: use more size_t in public api?
+ - misc: support for string view/range instead of char* would e.g. facilitate usage with Rust (#683, #3038, WIP string_view branch)
+
+ - demo: demonstrate using PushStyleVar() in more details.
+ - demo: add vertical separator demo
+ - demo: add virtual scrolling example?
+ - demo: demonstrate Plot offset
+ - demo: window size constraint: square demo is broken when resizing from edges (#1975), would need to rework the callback system to solve this
+
+ - examples: window minimize, maximize (#583)
+ - examples: provide a zero frame-rate/idle example.
+ - examples: dx11/dx12: try to use new swapchain blit models (#2970)
+ - backends: report it better when not able to create texture?
+ - backends: glfw: could go idle when minimized? if (glfwGetWindowAttrib(window, GLFW_ICONIFIED)) { glfwWaitEvents(); continue; } // issue: DeltaTime will be super high on resume, perhaps provide a way to let impl know (#440)
+ - backends: opengl: rename imgui_impl_opengl2 to impl_opengl_legacy and imgui_impl_opengl3 to imgui_impl_opengl? (#1900)
+ - backends: opengl: could use a single vertex buffer and glBufferSubData for uploads?
+ - backends: opengl: explicitly disable GL_STENCIL_TEST in bindings.
+ - backends: vulkan: viewport: support for synchronized swapping of multiple swap chains.
+ - backends: bgfx: https://gist.github.com/RichardGale/6e2b74bc42b3005e08397236e4be0fd0
+ - backends: emscriptem: with refactored examples, we could provide a direct imgui_impl_emscripten platform layer (see eg. https://github.com/floooh/sokol-samples/blob/master/html5/imgui-emsc.cc#L42)
+
+ - bindings: ways to use clang ast dump to generate bindings or helpers for bindings? (e.g. clang++ -Xclang -ast-dump=json imgui.h) (--> use https://github.com/dearimgui/dear_bindings)
+
+ - optimization: replace vsnprintf with stb_printf? using IMGUI_USE_STB_SPRINTF. (#1038 + needed for string_view)
+ - optimization: add clipping for multi-component widgets (SliderFloatX, ColorEditX, etc.). one problem is that nav branch can't easily clip parent group when there is a move request.
+ - optimization: add a flag to disable most of rendering, for the case where the user expect to skip it (#335)
+ - optimization: fully covered window (covered by another with non-translucent bg + WindowRounding worth of padding) may want to clip rendering.
+ - optimization: use another hash function than crc32, e.g. FNV1a
+ - optimization: turn some the various stack vectors into statically-sized arrays

Source/ThirdParty/ImGuiLibrary/Include/imconfig.h

@@ -1,72 +1,140 @@
 //-----------------------------------------------------------------------------
-// COMPILE-TIME OPTIONS FOR DEAR IMGUI
+// DEAR IMGUI COMPILE-TIME OPTIONS
 // Runtime options (clipboard callbacks, enabling various features, etc.) can generally be set via the ImGuiIO structure.
 // You can use ImGui::SetAllocatorFunctions() before calling ImGui::CreateContext() to rewire memory allocation functions.
 //-----------------------------------------------------------------------------
-// A) You may edit imconfig.h (and not overwrite it when updating imgui, or maintain a patch/branch with your modifications to imconfig.h)
-// B) or add configuration directives in your own file and compile with #define IMGUI_USER_CONFIG "myfilename.h"
-// If you do so you need to make sure that configuration settings are defined consistently _everywhere_ dear imgui is used, which include
-// the imgui*.cpp files but also _any_ of your code that uses imgui. This is because some compile-time options have an affect on data structures.
+// A) You may edit imconfig.h (and not overwrite it when updating Dear ImGui, or maintain a patch/rebased branch with your modifications to it)
+// B) or '#define IMGUI_USER_CONFIG "my_imgui_config.h"' in your project and then add directives in your own file without touching this template.
+//-----------------------------------------------------------------------------
+// You need to make sure that configuration settings are defined consistently _everywhere_ Dear ImGui is used, which include the imgui*.cpp
+// files but also _any_ of your code that uses Dear ImGui. This is because some compile-time options have an affect on data structures.
 // Defining those options in imconfig.h will ensure every compilation unit gets to see the same data structure layouts.
-// Call IMGUI_CHECKVERSION() from your .cpp files to verify that the data structures your files are using are matching the ones imgui.cpp is using.
+// Call IMGUI_CHECKVERSION() from your .cpp file to verify that the data structures your files are using are matching the ones imgui.cpp is using.
 //-----------------------------------------------------------------------------
 
 #pragma once
 
 //---- Define assertion handler. Defaults to calling assert().
+// If your macro uses multiple statements, make sure is enclosed in a 'do { .. } while (0)' block so it can be used as a single statement.
 //#define IM_ASSERT(_EXPR)  MyAssert(_EXPR)
 //#define IM_ASSERT(_EXPR)  ((void)(_EXPR))     // Disable asserts
 
-//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows.
-//#define IMGUI_API __declspec( dllexport )
-//#define IMGUI_API __declspec( dllimport )
+//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows
+// Using Dear ImGui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
+// - Windows DLL users: heaps and globals are not shared across DLL boundaries! You will need to call SetCurrentContext() + SetAllocatorFunctions()
+//   for each static/DLL boundary you are calling from. Read "Context and Memory Allocators" section of imgui.cpp for more details.
+//#define IMGUI_API __declspec(dllexport)                   // MSVC Windows: DLL export
+//#define IMGUI_API __declspec(dllimport)                   // MSVC Windows: DLL import
+//#define IMGUI_API __attribute__((visibility("default")))  // GCC/Clang: override visibility when set is hidden
 
-//---- Don't define obsolete functions/enums names. Consider enabling from time to time after updating to avoid using soon-to-be obsolete function/names.
+//---- Don't define obsolete functions/enums/behaviors. Consider enabling from time to time after updating to clean your code of obsolete function/names.
 //#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
 
-//---- Don't implement demo windows functionality (ShowDemoWindow()/ShowStyleEditor()/ShowUserGuide() methods will be empty)
-//---- It is very strongly recommended to NOT disable the demo windows during development. Please read the comments in imgui_demo.cpp.
-//#define IMGUI_DISABLE_DEMO_WINDOWS
+//---- Disable all of Dear ImGui or don't implement standard windows/tools.
+// It is very strongly recommended to NOT disable the demo windows and debug tool during development. They are extremely useful in day to day work. Please read comments in imgui_demo.cpp.
+//#define IMGUI_DISABLE                                     // Disable everything: all headers and source files will be empty.
+//#define IMGUI_DISABLE_DEMO_WINDOWS                        // Disable demo windows: ShowDemoWindow()/ShowStyleEditor() will be empty.
+//#define IMGUI_DISABLE_DEBUG_TOOLS                         // Disable metrics/debugger and other debug tools: ShowMetricsWindow(), ShowDebugLogWindow() and ShowIDStackToolWindow() will be empty.
 
 //---- Don't implement some functions to reduce linkage requirements.
-//#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS   // [Win32] Don't implement default clipboard handler. Won't use and link with OpenClipboard/GetClipboardData/CloseClipboard etc.
-//#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] Don't implement default IME handler. Won't use and link with ImmGetContext/ImmSetCompositionWindow.
-//#define IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS             // Don't implement ImFormatString/ImFormatStringV so you can implement them yourself if you don't want to link with vsnprintf.
-//#define IMGUI_DISABLE_MATH_FUNCTIONS                      // Don't implement ImFabs/ImSqrt/ImPow/ImFmod/ImCos/ImSin/ImAcos/ImAtan2 wrapper so you can implement them yourself. Declare your prototypes in imconfig.h.
+//#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS   // [Win32] Don't implement default clipboard handler. Won't use and link with OpenClipboard/GetClipboardData/CloseClipboard etc. (user32.lib/.a, kernel32.lib/.a)
+//#define IMGUI_ENABLE_WIN32_DEFAULT_IME_FUNCTIONS          // [Win32] [Default with Visual Studio] Implement default IME handler (require imm32.lib/.a, auto-link for Visual Studio, -limm32 on command-line for MinGW)
+//#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] [Default with non-Visual Studio compilers] Don't implement default IME handler (won't require imm32.lib/.a)
+//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function (clipboard, IME).
+//#define IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS      // [OSX] Implement default OSX clipboard handler (need to link with '-framework ApplicationServices', this is why this is not the default).
+//#define IMGUI_DISABLE_DEFAULT_SHELL_FUNCTIONS             // Don't implement default platform_io.Platform_OpenInShellFn() handler (Win32: ShellExecute(), require shell32.lib/.a, Mac/Linux: use system("")).
+//#define IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS            // Don't implement ImFormatString/ImFormatStringV so you can implement them yourself (e.g. if you don't want to link with vsnprintf)
+//#define IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS              // Don't implement ImFabs/ImSqrt/ImPow/ImFmod/ImCos/ImSin/ImAcos/ImAtan2 so you can implement them yourself.
+//#define IMGUI_DISABLE_FILE_FUNCTIONS                      // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle at all (replace them with dummies)
+//#define IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS              // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle so you can implement them yourself if you don't want to link with fopen/fclose/fread/fwrite. This will also disable the LogToTTY() function.
 //#define IMGUI_DISABLE_DEFAULT_ALLOCATORS                  // Don't implement default allocators calling malloc()/free() to avoid linking with them. You will need to call ImGui::SetAllocatorFunctions().
+//#define IMGUI_DISABLE_SSE                                 // Disable use of SSE intrinsics even if available
+
+//---- Enable Test Engine / Automation features.
+//#define IMGUI_ENABLE_TEST_ENGINE                          // Enable imgui_test_engine hooks. Generally set automatically by include "imgui_te_config.h", see Test Engine for details.
 
 //---- Include imgui_user.h at the end of imgui.h as a convenience
+// May be convenient for some users to only explicitly include vanilla imgui.h and have extra stuff included.
 //#define IMGUI_INCLUDE_IMGUI_USER_H
+//#define IMGUI_USER_H_FILENAME         "my_folder/my_imgui_user.h"
 
 //---- Pack colors to BGRA8 instead of RGBA8 (to avoid converting from one to another)
 //#define IMGUI_USE_BGRA_PACKED_COLOR
 
+//---- Use 32-bit for ImWchar (default is 16-bit) to support Unicode planes 1-16. (e.g. point beyond 0xFFFF like emoticons, dingbats, symbols, shapes, ancient languages, etc...)
+//#define IMGUI_USE_WCHAR32
+
 //---- Avoid multiple STB libraries implementations, or redefine path/filenames to prioritize another version
-// By default the embedded implementations are declared static and not available outside of imgui cpp files.
+// By default the embedded implementations are declared static and not available outside of Dear ImGui sources files.
 //#define IMGUI_STB_TRUETYPE_FILENAME   "my_folder/stb_truetype.h"
 //#define IMGUI_STB_RECT_PACK_FILENAME  "my_folder/stb_rect_pack.h"
+//#define IMGUI_STB_SPRINTF_FILENAME    "my_folder/stb_sprintf.h"    // only used if IMGUI_USE_STB_SPRINTF is defined.
 //#define IMGUI_DISABLE_STB_TRUETYPE_IMPLEMENTATION
 //#define IMGUI_DISABLE_STB_RECT_PACK_IMPLEMENTATION
+//#define IMGUI_DISABLE_STB_SPRINTF_IMPLEMENTATION                   // only disabled if IMGUI_USE_STB_SPRINTF is defined.
+
+//---- Use stb_sprintf.h for a faster implementation of vsnprintf instead of the one from libc (unless IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS is defined)
+// Compatibility checks of arguments and formats done by clang and GCC will be disabled in order to support the extra formats provided by stb_sprintf.h.
+//#define IMGUI_USE_STB_SPRINTF
+
+//---- Use FreeType to build and rasterize the font atlas (instead of stb_truetype which is embedded by default in Dear ImGui)
+// Requires FreeType headers to be available in the include path. Requires program to be compiled with 'misc/freetype/imgui_freetype.cpp' (in this repository) + the FreeType library (not provided).
+// On Windows you may use vcpkg with 'vcpkg install freetype --triplet=x64-windows' + 'vcpkg integrate install'.
+//#define IMGUI_ENABLE_FREETYPE
+
+//---- Use FreeType + plutosvg or lunasvg to render OpenType SVG fonts (SVGinOT)
+// Only works in combination with IMGUI_ENABLE_FREETYPE.
+// - lunasvg is currently easier to acquire/install, as e.g. it is part of vcpkg.
+// - plutosvg will support more fonts and may load them faster. It currently requires to be built manually but it is fairly easy. See misc/freetype/README for instructions.
+// - Both require headers to be available in the include path + program to be linked with the library code (not provided).
+// - (note: lunasvg implementation is based on Freetype's rsvg-port.c which is licensed under CeCILL-C Free Software License Agreement)
+//#define IMGUI_ENABLE_FREETYPE_PLUTOSVG
+//#define IMGUI_ENABLE_FREETYPE_LUNASVG
+
+//---- Use stb_truetype to build and rasterize the font atlas (default)
+// The only purpose of this define is if you want force compilation of the stb_truetype backend ALONG with the FreeType backend.
+//#define IMGUI_ENABLE_STB_TRUETYPE
 
 //---- Define constructor and implicit cast operators to convert back<>forth between your math types and ImVec2/ImVec4.
 // This will be inlined as part of ImVec2 and ImVec4 class declarations.
-/*
-#define IM_VEC2_CLASS_EXTRA                                                 \
-        ImVec2(const MyVec2& f) { x = f.x; y = f.y; }                       \
-        operator MyVec2() const { return MyVec2(x,y); }
 
-#define IM_VEC4_CLASS_EXTRA                                                 \
-        ImVec4(const MyVec4& f) { x = f.x; y = f.y; z = f.z; w = f.w; }     \
-        operator MyVec4() const { return MyVec4(x,y,z,w); }
+/*
+#define IM_VEC2_CLASS_EXTRA                                                     \
+        constexpr ImVec2(const FVector2D& f) : x(f.X), y(f.Y) {}                   \
+        operator FVector2D() const { return FVector2D(x,y); }
+
+#define IM_VEC4_CLASS_EXTRA                                                     \
+        constexpr ImVec4(const FVector4& f) : x(f.X), y(f.Y), z(f.Z), w(f.W) {}   \
+        operator FVector4() const { return FVector4(x,y,z,w); }
 */
 
-//---- Use 32-bit vertex indices (default is 16-bit) to allow meshes with more than 64K vertices. Render function needs to support it.
+//---- ...Or use Dear ImGui's own very basic math operators.
+#define IMGUI_DEFINE_MATH_OPERATORS
+
+//---- Use 32-bit vertex indices (default is 16-bit) is one way to allow large meshes with more than 64K vertices.
+// Your renderer backend will need to support it (most example renderer backends support both 16/32-bit indices).
+// Another way to allow large meshes while keeping 16-bit indices is to handle ImDrawCmd::VtxOffset in your renderer.
+// Read about ImGuiBackendFlags_RendererHasVtxOffset for details.
 //#define ImDrawIdx unsigned int
 
-//---- Tip: You can add extra functions within the ImGui:: namespace, here or in your own headers files.
+//---- Override ImDrawCallback signature (will need to modify renderer backends accordingly)
+//struct ImDrawList;
+//struct ImDrawCmd;
+//typedef void (*MyImDrawCallback)(const ImDrawList* draw_list, const ImDrawCmd* cmd, void* my_renderer_user_data);
+//#define ImDrawCallback MyImDrawCallback
+
+//---- Debug Tools: Macro to break in Debugger (we provide a default implementation of this in the codebase)
+// (use 'Metrics->Tools->Item Picker' to pick widgets with the mouse and break into them for easy debugging.)
+//#define IM_DEBUG_BREAK  IM_ASSERT(0)
+//#define IM_DEBUG_BREAK  __debugbreak()
+
+//---- Debug Tools: Enable slower asserts
+//#define IMGUI_DEBUG_PARANOID
+
+//---- Tip: You can add extra functions within the ImGui:: namespace from anywhere (e.g. your own sources/header files)
 /*
 namespace ImGui
 {
-    void MyFunction(const char* name, const MyMatrix44& v);
+    void MyFunction(const char* name, MyMatrix44* mtx);
 }
 */

Source/ThirdParty/ImGuiLibrary/Include/misc/stl/imgui_stl.h

@@ -1,22 +0,0 @@
-// imgui_stl.h
-// Wrappers for C++ standard library (STL) types (std::string, etc.)
-// This is also an example of how you may wrap your own similar types.
-
-// Compatibility:
-// - std::string support is only guaranteed to work from C++11. 
-//   If you try to use it pre-C++11, please share your findings (w/ info about compiler/architecture)
-
-// Changelog:
-// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
-
-#pragma once
-
-#include <string>
-
-namespace ImGui
-{
-    // ImGui::InputText() with std::string
-    // Because text input needs dynamic resizing, we need to setup a callback to grow the capacity
-    IMGUI_API bool  InputText(const char* label, std::string* str, ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
-    IMGUI_API bool  InputTextMultiline(const char* label, std::string* str, const ImVec2& size = ImVec2(0, 0), ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
-}

Source/ThirdParty/ImGuiLibrary/LICENSE.txt

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014-2018 Omar Cornut
+Copyright (c) 2014-2024 Omar Cornut
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

Source/ThirdParty/ImGuiLibrary/Private/imstb_rectpack.h

@@ -1,9 +1,19 @@
-// stb_rect_pack.h - v0.11 - public domain - rectangle packing
+// [DEAR IMGUI]
+// This is a slightly modified version of stb_rect_pack.h 1.01.
+// Grep for [DEAR IMGUI] to find the changes.
+// 
+// stb_rect_pack.h - v1.01 - public domain - rectangle packing
 // Sean Barrett 2014
 //
 // Useful for e.g. packing rectangular textures into an atlas.
 // Does not do rotation.
 //
+// Before #including,
+//
+//    #define STB_RECT_PACK_IMPLEMENTATION
+//
+// in the file that you want to have the implementation.
+//
 // Not necessarily the awesomest packing method, but better than
 // the totally naive one in stb_truetype (which is primarily what
 // this is meant to replace).
@@ -28,12 +38,16 @@
 //  Minor features
 //    Martins Mozeiko
 //    github:IntellectualKitty
-//    
+//
 //  Bugfixes / warning fixes
 //    Jeremy Jaussaud
+//    Fabian Giesen
 //
 // Version history:
 //
+//     1.01  (2021-07-11)  always use large rect mode, expose STBRP__MAXVAL in public section
+//     1.00  (2019-02-25)  avoid small space waste; gracefully fail too-wide rectangles
+//     0.99  (2019-02-07)  warning fixes
 //     0.11  (2017-03-03)  return packing success/fail result
 //     0.10  (2016-10-25)  remove cast-away-const to avoid warnings
 //     0.09  (2016-08-27)  fix compiler warnings
@@ -72,11 +86,10 @@ typedef struct stbrp_context stbrp_context;
 typedef struct stbrp_node    stbrp_node;
 typedef struct stbrp_rect    stbrp_rect;
 
-#ifdef STBRP_LARGE_RECTS
 typedef int            stbrp_coord;
-#else
-typedef unsigned short stbrp_coord;
-#endif
+
+#define STBRP__MAXVAL  0x7fffffff
+// Mostly for internal use, but this is the maximum supported coordinate value.
 
 STBRP_DEF int stbrp_pack_rects (stbrp_context *context, stbrp_rect *rects, int num_rects);
 // Assign packed locations to rectangles. The rectangles are of type
@@ -206,7 +219,7 @@ struct stbrp_context
 
 #ifdef _MSC_VER
 #define STBRP__NOTUSED(v)  (void)(v)
-#define STBRP__CDECL __cdecl
+#define STBRP__CDECL       __cdecl
 #else
 #define STBRP__NOTUSED(v)  (void)sizeof(v)
 #define STBRP__CDECL
@@ -252,9 +265,6 @@ STBRP_DEF void stbrp_setup_allow_out_of_mem(stbrp_context *context, int allow_ou
 STBRP_DEF void stbrp_init_target(stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes)
 {
    int i;
-#ifndef STBRP_LARGE_RECTS
-   STBRP_ASSERT(width <= 0xffff && height <= 0xffff);
-#endif
 
    for (i=0; i < num_nodes-1; ++i)
       nodes[i].next = &nodes[i+1];
@@ -273,11 +283,7 @@ STBRP_DEF void stbrp_init_target(stbrp_context *context, int width, int height,
    context->extra[0].y = 0;
    context->extra[0].next = &context->extra[1];
    context->extra[1].x = (stbrp_coord) width;
-#ifdef STBRP_LARGE_RECTS
    context->extra[1].y = (1<<30);
-#else
-   context->extra[1].y = 65535;
-#endif
    context->extra[1].next = NULL;
 }
 
@@ -349,6 +355,13 @@ static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int widt
    width -= width % c->align;
    STBRP_ASSERT(width % c->align == 0);
 
+   // if it can't possibly fit, bail immediately
+   if (width > c->width || height > c->height) {
+      fr.prev_link = NULL;
+      fr.x = fr.y = 0;
+      return fr;
+   }
+
    node = c->active_head;
    prev = &c->active_head;
    while (node->x + width <= c->width) {
@@ -412,11 +425,11 @@ static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int widt
          }
          STBRP_ASSERT(node->next->x > xpos && node->x <= xpos);
          y = stbrp__skyline_find_min_y(c, node, xpos, width, &waste);
-         if (y + height < c->height) {
+         if (y + height <= c->height) {
             if (y <= best_y) {
                if (y < best_y || waste < best_waste || (waste==best_waste && xpos < best_x)) {
                   best_x = xpos;
-                  STBRP_ASSERT(y <= best_y);
+                  //STBRP_ASSERT(y <= best_y); [DEAR IMGUI]
                   best_y = y;
                   best_waste = waste;
                   best = prev;
@@ -424,7 +437,7 @@ static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int widt
             }
          }
          tail = tail->next;
-      }         
+      }
    }
 
    fr.prev_link = best;
@@ -530,12 +543,6 @@ static int STBRP__CDECL rect_original_order(const void *a, const void *b)
    return (p->was_packed < q->was_packed) ? -1 : (p->was_packed > q->was_packed);
 }
 
-#ifdef STBRP_LARGE_RECTS
-#define STBRP__MAXVAL  0xffffffff
-#else
-#define STBRP__MAXVAL  0xffff
-#endif
-
 STBRP_DEF int stbrp_pack_rects(stbrp_context *context, stbrp_rect *rects, int num_rects)
 {
    int i, all_rects_packed = 1;
@@ -543,9 +550,6 @@ STBRP_DEF int stbrp_pack_rects(stbrp_context *context, stbrp_rect *rects, int nu
    // we use the 'was_packed' field internally to allow sorting/unsorting
    for (i=0; i < num_rects; ++i) {
       rects[i].was_packed = i;
-      #ifndef STBRP_LARGE_RECTS
-      STBRP_ASSERT(rects[i].w <= 0xffff && rects[i].h <= 0xffff);
-      #endif
    }
 
    // sort according to heuristic
@@ -586,38 +590,38 @@ This software is available under 2 licenses -- choose whichever you prefer.
 ------------------------------------------------------------------------------
 ALTERNATIVE A - MIT License
 Copyright (c) 2017 Sean Barrett
-Permission is hereby granted, free of charge, to any person obtaining a copy of 
-this software and associated documentation files (the "Software"), to deal in 
-the Software without restriction, including without limitation the rights to 
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
-of the Software, and to permit persons to whom the Software is furnished to do 
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
 so, subject to the following conditions:
-The above copyright notice and this permission notice shall be included in all 
+The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 ------------------------------------------------------------------------------
 ALTERNATIVE B - Public Domain (www.unlicense.org)
 This is free and unencumbered software released into the public domain.
-Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 
-software, either in source code form or as a compiled binary, for any purpose, 
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
+software, either in source code form or as a compiled binary, for any purpose,
 commercial or non-commercial, and by any means.
-In jurisdictions that recognize copyright laws, the author or authors of this 
-software dedicate any and all copyright interest in the software to the public 
-domain. We make this dedication for the benefit of the public at large and to 
-the detriment of our heirs and successors. We intend this dedication to be an 
-overt act of relinquishment in perpetuity of all present and future rights to 
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and to
+the detriment of our heirs and successors. We intend this dedication to be an
+overt act of relinquishment in perpetuity of all present and future rights to
 this software under copyright law.
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
-AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
-ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 ------------------------------------------------------------------------------
 */

Source/ThirdParty/ImGuiLibrary/Private/misc/stl/imgui_stl.cpp

@@ -1,61 +0,0 @@
-// imgui_stl.cpp
-// Wrappers for C++ standard library (STL) types (std::string, etc.)
-// This is also an example of how you may wrap your own similar types.
-
-// Compatibility:
-// - std::string support is only guaranteed to work from C++11. 
-//   If you try to use it pre-C++11, please share your findings (w/ info about compiler/architecture)
-
-#include "imgui.h"
-#include "imgui_stl.h"
-
-struct InputTextCallback_UserData
-{
-    std::string*            Str;
-    ImGuiInputTextCallback  ChainCallback;
-    void*                   ChainCallbackUserData;
-};
-
-static int InputTextCallback(ImGuiInputTextCallbackData* data)
-{
-    InputTextCallback_UserData* user_data = (InputTextCallback_UserData*)data->UserData;
-    if (data->EventFlag == ImGuiInputTextFlags_CallbackResize)
-    {
-        // Resize string callback
-        std::string* str = user_data->Str;
-        IM_ASSERT(data->Buf == str->c_str());
-        str->resize(data->BufTextLen);
-        data->Buf = (char*)str->c_str();
-    }
-    else if (user_data->ChainCallback)
-    {
-        // Forward to user callback, if any
-        data->UserData = user_data->ChainCallbackUserData;
-        return user_data->ChainCallback(data);
-    }
-    return 0;
-}
-
-bool ImGui::InputText(const char* label, std::string* str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
-{
-    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
-    flags |= ImGuiInputTextFlags_CallbackResize;
-
-    InputTextCallback_UserData cb_user_data;
-    cb_user_data.Str = str;
-    cb_user_data.ChainCallback = callback;
-    cb_user_data.ChainCallbackUserData = user_data;
-    return InputText(label, (char*)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
-}
-
-bool ImGui::InputTextMultiline(const char* label, std::string* str, const ImVec2& size, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
-{
-    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
-    flags |= ImGuiInputTextFlags_CallbackResize;
-
-    InputTextCallback_UserData cb_user_data;
-    cb_user_data.Str = str;
-    cb_user_data.ChainCallback = callback;
-    cb_user_data.ChainCallbackUserData = user_data;
-    return InputTextMultiline(label, (char*)str->c_str(), str->capacity() + 1, size, flags, InputTextCallback, &cb_user_data);
-}

Source/ThirdParty/ImGuiLibrary/README.md

@@ -1,332 +0,0 @@
-dear imgui,
-=====
-[![Build Status](https://travis-ci.org/ocornut/imgui.svg?branch=master)](https://travis-ci.org/ocornut/imgui)
-[![Coverity Status](https://scan.coverity.com/projects/4720/badge.svg)](https://scan.coverity.com/projects/4720)
-
-_(This library is free but needs your support to sustain its development. There are many desirable features and maintenance ahead. If you are an individual using dear imgui, please consider donating via Patreon or PayPal. If your company is using dear imgui, please consider financial support (e.g. sponsoring a few weeks/months of development. I can invoice for technical support, custom development etc. Email: omarcornut at gmail)._
-
-Monthly donations via Patreon:
-<br>[![Patreon](https://cloud.githubusercontent.com/assets/8225057/5990484/70413560-a9ab-11e4-8942-1a63607c0b00.png)](http://www.patreon.com/imgui)
-
-One-off donations via PayPal:
-<br>[![PayPal](https://www.paypalobjects.com/en_US/i/btn/btn_donate_LG.gif)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=5Q73FPZ9C526U)
-
-Dear ImGui is a bloat-free graphical user interface library for C++. It outputs optimized vertex buffers that you can render anytime in your 3D-pipeline enabled application. It is fast, portable, renderer agnostic and self-contained (no external dependencies).
-
-Dear ImGui is designed to enable fast iterations and to empower programmers to create content creation tools and visualization / debug tools (as opposed to UI for the average end-user). It favors simplicity and productivity toward this goal, and lacks certain features normally found in more high-level libraries.
-
-Dear ImGui is particularly suited to integration in games engine (for tooling), real-time 3D applications, fullscreen applications, embedded applications, or any applications on consoles platforms where operating system features are non-standard. 
-
-Dear ImGui is self-contained within a few files that you can easily copy and compile into your application/engine:
-- imgui.cpp
-- imgui.h
-- imgui_demo.cpp
-- imgui_draw.cpp
-- imgui_widgets.cpp
-- imgui_internal.h
-- imconfig.h (empty by default, user-editable)
-- stb_rect_pack.h
-- stb_textedit.h
-- stb_truetype.h
-
-No specific build process is required. You can add the .cpp files to your project or #include them from an existing file.
-
-### Usage
-
-Your code passes mouse/keyboard/gamepad inputs and settings to Dear ImGui (see example applications for more details). After Dear ImGui is setup, you can use it from \_anywhere\_ in your program loop:
-
-Code:
-```cpp
-ImGui::Text("Hello, world %d", 123);
-if (ImGui::Button("Save"))
-{
-    // do stuff
-}
-ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
-ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
-```
-Result:
-<br>![sample code output](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/code_sample_02.png)
-<br>_(settings: Dark style (left), Light style (right) / Font: Roboto-Medium, 16px / Rounding: 5)_
-
-Code:
-```cpp
-// Create a window called "My First Tool", with a menu bar.
-ImGui::Begin("My First Tool", &my_tool_active, ImGuiWindowFlags_MenuBar);
-if (ImGui::BeginMenuBar())
-{
-    if (ImGui::BeginMenu("File"))
-    {
-        if (ImGui::MenuItem("Open..", "Ctrl+O")) { /* Do stuff */ }
-        if (ImGui::MenuItem("Save", "Ctrl+S"))   { /* Do stuff */ }
-        if (ImGui::MenuItem("Close", "Ctrl+W"))  { my_tool_active = false; }
-        ImGui::EndMenu();
-    }
-    ImGui::EndMenuBar();
-}
-
-// Edit a color (stored as ~4 floats)
-ImGui::ColorEdit4("Color", my_color);
-
-// Plot some values
-const float my_values[] = { 0.2f, 0.1f, 1.0f, 0.5f, 0.9f, 2.2f };
-ImGui::PlotLines("Frame Times", my_values, IM_ARRAYSIZE(my_values));
- 
-// Display contents in a scrolling region
-ImGui::TextColored(ImVec4(1,1,0,1), "Important Stuff");
-ImGui::BeginChild("Scrolling");
-for (int n = 0; n < 50; n++)
-    ImGui::Text("%04d: Some text", n);
-ImGui::EndChild();
-ImGui::End();
-```
-Result:
-<br>![sample code output](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/code_sample_03_color.gif)
-
-### How it works
-
-Check out the References section if you want to understand the core principles behind the IMGUI paradigm. An IMGUI tries to minimize state duplication, state synchronization and state storage from the user's point of view. It is less error prone (less code and less bugs) than traditional retained-mode interfaces, and lends itself to create dynamic user interfaces. 
-
-Dear ImGui outputs vertex buffers and command lists that you can easily render in your application. The number of draw calls and state changes is typically very small. Because it doesn't know or touch graphics state directly, you can call ImGui commands anywhere in your code (e.g. in the middle of a running algorithm, or in the middle of your own rendering process). Refer to the sample applications in the examples/ folder for instructions on how to integrate dear imgui with your existing codebase. 
-
-_A common misunderstanding is to mistake immediate mode gui for immediate mode rendering, which usually implies hammering your driver/GPU with a bunch of inefficient draw calls and state changes as the gui functions are called. This is NOT what Dear ImGui does. Dear ImGui outputs vertex buffers and a small list of draw calls batches. It never touches your GPU directly. The draw call batches are decently optimal and you can render them later, in your app or even remotely._
-
-Dear ImGui allows you create elaborate tools as well as very short-lived ones. On the extreme side of short-liveness: using the Edit&Continue (hot code reload) feature of modern compilers you can add a few widgets to tweaks variables while your application is running, and remove the code a minute later! Dear ImGui is not just for tweaking values. You can use it to trace a running algorithm by just emitting text commands. You can use it along with your own reflection data to browse your dataset live. You can use it to expose the internals of a subsystem in your engine, to create a logger, an inspection tool, a profiler, a debugger, an entire game making editor/framework, etc.  
-
-Demo Binaries
--------------
-
-You should be able to build the examples from sources (tested on Windows/Mac/Linux). If you don't, let me know! If you want to have a quick look at some Dear ImGui features, you can download Windows binaries of the demo app here:
-- [imgui-demo-binaries-20180512.zip](http://www.miracleworld.net/imgui/binaries/imgui-demo-binaries-20180512.zip) (Windows binaries, Dear ImGui 1.61 WIP built 2018/05/12, 5 executables)
-
-The demo applications are unfortunately not yet DPI aware so expect some blurriness on a 4K screen. For DPI awareness you can load/reload your font at different scale, and scale your Style with `style.ScaleAllSizes()`.
-
-Bindings
---------
-
-Integrating Dear ImGui within your custom engine is a matter of 1) wiring mouse/keyboard/gamepad inputs 2) uploading one texture to your GPU/render engine 3) providing a render function that can bind textures and render textured triangles. The [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder is populated with applications doing just that. If you are an experienced programmer and at ease with those concepts, it should take you less than an hour to integrate Dear ImGui in your custom engine, but make sure to spend time reading the FAQ, the comments and other documentation!
-
-_NB: those third-party bindings may be more or less maintained, more or less close to the original API (as people who create language bindings sometimes haven't used the C++ API themselves.. for the good reason that they aren't C++ users). Dear ImGui was designed with C++ in mind and some of the subtleties may be lost in translation with other languages. If your language supports it, I would suggest replicating the function overloading and default parameters used in the original, else the API may be harder to use. In doubt, please check the original C++ version first!_
-
-Languages: (third-party bindings)
-- C: [cimgui](https://github.com/Extrawurst/cimgui) or [sonoro1234's cimgui](https://github.com/sonoro1234/cimgui) (more recent update), also see [#1879](https://github.com/ocornut/imgui/issues/1879)
-- C#/.Net: [ImGui.NET](https://github.com/mellinoe/ImGui.NET)
-- ChaiScript: [imgui-chaiscript](https://github.com/JuJuBoSc/imgui-chaiscript)
-- D: [DerelictImgui](https://github.com/Extrawurst/DerelictImgui)
-- Go: [go-imgui](https://github.com/Armored-Dragon/go-imgui)
-- Haxe/hxcpp: [linc_imgui](https://github.com/Aidan63/linc_imgui)
-- Java: [jimgui](https://github.com/ice1000/jimgui)
-- JavaScript: [imgui-js](https://github.com/flyover/imgui-js)
-- Lua: [imgui_lua_bindings](https://github.com/patrickriordan/imgui_lua_bindings) or [lua-ffi-bindings](https://github.com/thenumbernine/lua-ffi-bindings)
-- Odin: [odin-dear_imgui](https://github.com/ThisDrunkDane/odin-dear_imgui)
-- Pascal: [imgui-pas](https://github.com/dpethes/imgui-pas)
-- PureBasic: [pb-cimgui](https://github.com/hippyau/pb-cimgui)
-- Python [CyImGui](https://github.com/chromy/cyimgui) or [pyimgui](https://github.com/swistakm/pyimgui)
-- Rust: [imgui-rs](https://github.com/Gekkio/imgui-rs)
-- Swift [swift-imgui](https://github.com/mnmly/Swift-imgui)
-
-Frameworks:
-- Renderers: DirectX 9, DirectX 10, DirectX 11, DirectX 12, Metal, OpenGL2, OpenGL3+/ES2/ES3, Vulkan: [examples/](https://github.com/ocornut/imgui/tree/master/examples)
-- Platform: GLFW, SDL, Win32, OSX, Freeglut: [examples/](https://github.com/ocornut/imgui/tree/master/examples)
-- Framework: Allegro 5, Marmalade: [examples/](https://github.com/ocornut/imgui/tree/master/examples)
-- Unmerged PR: SDL2 + OpenGLES + Emscripten: [#336](https://github.com/ocornut/imgui/pull/336)
-- Unmerged PR: Android: [#421](https://github.com/ocornut/imgui/pull/421)
-- Unmerged PR: ORX: [#1843](https://github.com/ocornut/imgui/pull/1843)
-- Cinder: [Cinder-ImGui](https://github.com/simongeilfus/Cinder-ImGui)
-- Cocos2d-x: [imguix](https://github.com/c0i/imguix), [issue #551](https://github.com/ocornut/imgui/issues/551)
-- Flexium: [FlexGUI](https://github.com/DXsmiley/FlexGUI)
-- GML/GameMakerStudio2: [ImGuiGML](https://marketplace.yoyogames.com/assets/6221/imguigml)
-- Irrlicht: [IrrIMGUI](https://github.com/ZahlGraf/IrrIMGUI)
-- Ogre: [ogreimgui](https://bitbucket.org/LMCrashy/ogreimgui/src)
-- OpenFrameworks: [ofxImGui](https://github.com/jvcleave/ofxImGui)
-- OpenSceneGraph/OSG: [gist](https://gist.github.com/fulezi/d2442ca7626bf270226014501357042c)
-- LÖVE+Lua: [love-imgui](https://github.com/slages/love-imgui)
-- Magnum: [magnum-imgui](https://github.com/lecopivo/magnum-imgui), [MagnumImguiPort](https://github.com/lecopivo/MagnumImguiPort)
-- NanoRT: [syoyo/imgui](https://github.com/syoyo/imgui/tree/nanort)
-- Qt3d: [imgui-qt3d](https://github.com/alpqr/imgui-qt3d), QOpenGLWindow [qtimgui](https://github.com/ocornut/imgui/issues/1910)
-- SFML: [imgui-sfml](https://github.com/EliasD/imgui-sfml)
-- Software renderer: [imgui_software_renderer](https://github.com/emilk/imgui_software_renderer)
-- Unreal Engine 4: [segross/UnrealImGui](https://github.com/segross/UnrealImGui) or [sronsse/UnrealEngine_ImGui](https://github.com/sronsse/UnrealEngine_ImGui)
-
-For other bindings: see [Bindings](https://github.com/ocornut/imgui/wiki/Bindings/). Also see [Wiki](https://github.com/ocornut/imgui/wiki) for more links and ideas.
-
-Roadmap
--------
-Some of the goals for 2018 are:
-- Finish work on gamepad/keyboard controls. (see [#787](https://github.com/ocornut/imgui/issues/787))
-- Finish work on viewports and multiple OS windows management. (see [#1542](https://github.com/ocornut/imgui/issues/1542))
-- Finish work on docking, tabs. (see [#351](https://github.com/ocornut/imgui/issues/351#issuecomment-346865709))
-- Make Columns better. (they are currently pretty terrible!)
-- Make the examples look better, improve styles, improve font support, make the examples hi-DPI aware.
-
-Gallery
--------
-User screenshots:
-<br>[Gallery Part 1](https://github.com/ocornut/imgui/issues/123) (Feb 2015 to Feb 2016)
-<br>[Gallery Part 2](https://github.com/ocornut/imgui/issues/539) (Feb 2016 to Aug 2016)
-<br>[Gallery Part 3](https://github.com/ocornut/imgui/issues/772) (Aug 2016 to Jan 2017)
-<br>[Gallery Part 4](https://github.com/ocornut/imgui/issues/973) (Jan 2017 to Aug 2017)
-<br>[Gallery Part 5](https://github.com/ocornut/imgui/issues/1269) (Aug 2017 to Feb 2018)
-<br>[Gallery Part 6](https://github.com/ocornut/imgui/issues/1607) (Feb 2018 to June 2018)
-<br>[Gallery Part 7](https://github.com/ocornut/imgui/issues/1902) (June 2018 onward)
-<br>Also see the [Mega screenshots](https://github.com/ocornut/imgui/issues/1273) for an idea of the available features.
-
-Various tools
-[![screenshot game](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v149/gallery_TheDragonsTrap-01-thumb.jpg)](https://cloud.githubusercontent.com/assets/8225057/20628927/33e14cac-b329-11e6-80f6-9524e93b048a.png)
-
-[![screenshot tool](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/editor_white_preview.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/editor_white.png)
-
-![screenshot demo](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/v160-misc-classic.png)
-
-[![screenshot profiler](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v148/profiler-880.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v148/profiler.png)
-
-Dear ImGui can load TTF/OTF fonts. UTF-8 is supported for text display and input. Here using Arial Unicode font to display Japanese. Initialize custom font with:
-Code:
-```cpp
-ImGuiIO& io = ImGui::GetIO();
-io.Fonts->AddFontFromFileTTF("NotoSansCJKjp-Medium.otf", 20.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
-```
-```cpp
-ImGui::Text(u8"こんにちは！テスト %d", 123);
-if (ImGui::Button(u8"ロード"))
-{
-    // do stuff
-}
-ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
-ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
-```
-Result:
-<br>![sample code output](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/code_sample_02_jp.png)
-<br>_(settings: Dark style (left), Light style (right) / Font: NotoSansCJKjp-Medium, 20px / Rounding: 5)_
-
-References
-----------
-
-The Immediate Mode GUI paradigm may at first appear unusual to some users. This is mainly because "Retained Mode" GUIs have been so widespread and predominant. The following links can give you a better understanding about how Immediate Mode GUIs works. 
-- [Johannes 'johno' Norneby's article](http://www.johno.se/book/imgui.html).
-- [A presentation by Rickard Gustafsson and Johannes Algelind](http://www.cse.chalmers.se/edu/year/2011/course/TDA361/Advanced%20Computer%20Graphics/IMGUI.pdf).
-- [Jari Komppa's tutorial on building an ImGui library](http://iki.fi/sol/imgui/).
-- [Casey Muratori's original video that popularized the concept](https://mollyrocket.com/861).
-- [Nicolas Guillemot's CppCon'16 flash-talk about Dear ImGui](https://www.youtube.com/watch?v=LSRJ1jZq90k).
-- [Thierry Excoffier's Zero Memory Widget](http://perso.univ-lyon1.fr/thierry.excoffier/ZMW/).
-
-See the [Wiki](https://github.com/ocornut/imgui/wiki) and [Bindings](https://github.com/ocornut/imgui/wiki/Bindings) for third-party bindings to different languages and frameworks.
-
-Support Forums
---------------
-
-If you have issues with: compiling, linking, adding fonts, running or displaying Dear ImGui, or wiring inputs: please post on the Discourse forum: https://discourse.dearimgui.org/c/getting-started.
-
-For any other questions, bug reports, requests, feedback, you may post on https://github.com/ocornut/imgui/issues.
-
-Frequently Asked Question (FAQ)
--------------------------------
-
-**Where is the documentation?**
-
-- The documentation is at the top of imgui.cpp + effectively imgui.h. 
-- Example code is in imgui_demo.cpp and particularly the ImGui::ShowDemoWindow() function. It covers most features of ImGui so you can read the code and call the function itself to see its output. 
-- Standalone example applications using e.g. OpenGL/DirectX are provided in the examples/ folder. 
-- We obviously needs better documentation! Consider contributing or becoming a [Patron](http://www.patreon.com/imgui) to promote this effort.
-
-**Which version should I get?**
-
-I occasionally tag [Releases](https://github.com/ocornut/imgui/releases) but it is generally safe and recommended to sync to master/latest. The library is fairly stable and regressions tend to be fixed fast when reported. 
-
-**Who uses Dear ImGui?**
-
-See the [Software using dear imgui page](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) for an (incomplete) list of games/software which are publicly known to use dear imgui. Please add yours if you can!
-
-**Why the odd dual naming, "dear imgui" vs "ImGui"?**
-
-The library started its life and is best known as "ImGui" only due to the fact that I didn't give it a proper name when I released it. However, the term IMGUI (immediate-mode graphical user interface) was coined before and is being used in variety of other situations. It seemed confusing and unfair to hog the name. To reduce the ambiguity without affecting existing codebases, I have decided on an alternate, longer name "dear imgui" that people can use to refer to this specific library in ambiguous situations.
-
-**How can I tell whether to dispatch mouse/keyboard to imgui or to my application?**
-<br>**How can I display an image? What is ImTextureID, how does it works?**
-<br>**How can I have multiple widgets with the same label or without a label? A primer on labels and the ID Stack.**
-<br>**How can I use my own math types instead of ImVec2/ImVec4?**
-<br>**How can I load a different font than the default?**
-<br>**How can I easily use icons in my application?**
-<br>**How can I load multiple fonts?**
-<br>**How can I display and input non-latin characters such as Chinese, Japanese, Korean, Cyrillic?**
-<br>**How can I use the drawing facilities without an Dear ImGui window? (using ImDrawList API)**
-<br>**I integrated Dear ImGui in my engine and the text or lines are blurry..**
-<br>**I integrated Dear ImGui in my engine and some elements are disappearing when I move windows around..**
-<br>**How can I help?**
-
-See the FAQ in imgui.cpp for answers.
-
-**How do you use Dear ImGui on a platform that may not have a mouse or keyboard?**
-
-You can control Dear ImGui with a gamepad, see the explanation in imgui.cpp about how to use the navigation feature (short version: map your gamepad inputs into the `io.NavInputs[]` array and set `io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad`).
-
-You can share your computer mouse seamlessly with your console/tablet/phone using [Synergy](http://synergy-project.org). This is the preferred solution for developer productivity. In particular, their [micro-synergy-client](https://github.com/symless/micro-synergy-client) repo there is _uSynergy.c_ sources for a small embeddable that you can use on any platform to connect to your host PC using Synergy 1.x. You may also use a third party solution such as [Remote ImGui](https://github.com/JordiRos/remoteimgui).
-
-For touch inputs, you can increase the hit box of widgets (via the _style.TouchPadding_ setting) to accommodate a little for the lack of precision of touch inputs, but it is recommended you use a mouse or gamepad to allow optimizing for screen real-estate and precision.
-
-**Can you create elaborate/serious tools with Dear ImGui?**
-
-Yes. People have written game editors, data browsers, debuggers, profilers and all sort of non-trivial tools with the library. In my experience the simplicity of the API is very empowering. Your UI runs close to your live data. Make the tools always-on and everybody in the team will be inclined to create new tools (as opposed to more "offline" UI toolkits where only a fraction of your team effectively creates tools). The list of sponsors below is also an indicator that serious game teams have been using the library.
-
-Dear ImGui is very programmer centric and the immediate-mode GUI paradigm might requires you to readjust some habits before you can realize its full potential. Dear ImGui is about making things that are simple, efficient and powerful.
-
-**Can you reskin the look of Dear ImGui?**
-
-You can alter the look of the interface to some degree: changing colors, sizes, padding, rounding, fonts. However, as Dear ImGui is designed and optimized to create debug tools, the amount of skinning you can apply is limited. There is only so much you can stray away from the default look and feel of the interface. Below is a screenshot from [LumixEngine](https://github.com/nem0/LumixEngine) with custom colors + a docking/tabs extension (both of which you can find in the Issues section and will eventually be merged):
-
-![LumixEngine](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v151/lumix-201710-rearranged.png)
-
-**Why using C++ (as opposed to C)?**
-
-Dear ImGui takes advantage of a few C++ languages features for convenience but nothing anywhere Boost-insanity/quagmire. Dear ImGui does NOT require C++11 so it can be used with most old C++ compilers. Dear ImGui doesn't use any C++ header file. Language-wise, function overloading and default parameters are used to make the API easier to use and code more terse. Doing so I believe the API is sitting on a sweet spot and giving up on those features would make the API more cumbersome. Other features such as namespace, constructors and templates (in the case of the ImVector<> class) are also relied on as a convenience.
-
-There is a [c-api for ImGui (cimgui)](https://github.com/Extrawurst/cimgui) by Stephan Dilly + a newer, [auto-generated cimgui](https://github.com/sonoro1234/cimgui) by sonoro1234. Both are designed for binding other languages. I would suggest using your target language functionalities to try replicating the function overloading and default parameters used in C++ else the API may be harder to use. Also see [Bindings](https://github.com/ocornut/imgui/wiki/Bindings) for third-party bindings to other languages.
-
-Support dear imgui
-------------------
-
-**How can I help financing further development of Dear ImGui?**
-
-Your contributions are keeping the library alive. If you are an individual using dear imgui, please consider donating to enable me to spend more time improving the library.
-
-Monthly donations via Patreon:
-<br>[![Patreon](https://cloud.githubusercontent.com/assets/8225057/5990484/70413560-a9ab-11e4-8942-1a63607c0b00.png)](http://www.patreon.com/imgui)
-
-One-off donations via PayPal:
-<br>[![PayPal](https://www.paypalobjects.com/en_US/i/btn/btn_donate_LG.gif)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=5Q73FPZ9C526U)
-
-Ongoing dear imgui development is financially supported on [**Patreon**](http://www.patreon.com/imgui) and by private sponsors.
-If your company uses dear imgui, please consider financial support (e.g. sponsoring a few weeks/months of development. I can also invoice for private support, custom development etc. contact me for details: omarcornut at gmail). Thanks! 
-
-**Platinum-chocolate sponsors**
-- Blizzard Entertainment.
-
-**Double-chocolate sponsors**
-- Media Molecule, Mobigame, Insomniac Games, Aras Pranckevičius, Lizardcube, Greggman, DotEmu, Nadeo, Supercell, Runner, Artometa, Friendly Shade.
-
-**Salty caramel supporters**
-- Jetha Chan, Wild Sheep Studio, Pastagames, Mārtiņš Možeiko, Daniel Collin, Recognition Robotics, Chris Genova, ikrima, Glenn Fiedler, Geoffrey Evans, Dakko Dakko, Mercury Labs, Singularity Demo Group, Mischa Alff, Sebastien Ronsse, Lionel Landwerlin, Nikolay Ivanov, Ron Gilbert, Brandon Townsend, Nikhil Deshpande, Cort Stratton, drudru, Harfang 3D, Jeff Roberts.
-
-**Caramel supporters**
-- Michel Courtine, César Leblic, Dale Kim, Alex Evans, Rui Figueira, Paul Patrashcu, Jerome Lanquetot, Ctrl Alt Ninja, Paul Fleming, Neil Henning, Stephan Dilly, Neil Blakey-Milner, Aleksei, NeiloGD, Justin Paver, FiniteSol, Vincent Pancaldi, James Billot, Robin Hübner, furrtek, Eric, Simon Barratt, Game Atelier, Julian Bosch, Simon Lundmark, Vincent Hamm, Farhan Wali, Matt Reyer, Colin Riley, Victor Martins, Josh Simmons, Garrett Hoofman, Sergio Gonzales, Andrew Berridge, Roy Eltham, Game Preservation Society, Kit framework, Josh Faust, Martin Donlon, Quinton, Felix, Andrew Belt, Codecat, Cort Stratton, Claudio Canepa, Doug McNabb, Emmanuel Julien, Guillaume Chereau, Jeffrey Slutter, Jeremiah Deckard, r-lyeh, Roger Clark, Nekith, Joshua Fisher, Malte Hoffmann, Mustafa Karaalioglu, Merlyn Morgan-Graham, Per Vognsen, Fabian Giesen, Jan Staubach, Matt Hargett, John Shearer, Jesse Chounard, kingcoopa, Miloš Tošić, Jonas Bernemann, Johan Andersson, Nathan Hartman, Michael Labbe, Tomasz Golebiowski, Louis Schnellbach, Felipe Alfonso, Jimmy Andrews, Bojan Endrovski, Robin Berg Pettersen, Rachel Crawford, Edsel Malasig, Andrew Johnson, Sean Hunter, Jordan Mellow, Nefarius Software Solutions, Laura Wieme, Robert Nix, Mick Honey, Astrofra, Jonas Lehmann, Steven Kah Hien Wong, Bartosz Bielecki, Oscar Penas, A M, Liam Moynihan.
-
-And all other supporters; THANK YOU!
-(Please contact me if you would like to be added or removed from this list)
-
-Credits
--------
-
-Developed by [Omar Cornut](http://www.miracleworld.net) and every direct or indirect contributors to the GitHub. The early version of this library was developed with the support of [Media Molecule](http://www.mediamolecule.com) and first used internally on the game [Tearaway](http://tearaway.mediamolecule.com). 
-
-I first discovered imgui principles at [Q-Games](http://www.q-games.com) where Atman had dropped his own simple imgui implementation in the codebase, which I spent quite some time improving and thinking about. It turned out that Atman was exposed to the concept directly by working with Casey. When I moved to Media Molecule I rewrote a new library trying to overcome the flaws and limitations of the first one I've worked with. It became this library and since then I have spent an unreasonable amount of time iterating on it. 
-
-Embeds [ProggyClean.ttf](http://upperbounds.net) font by Tristan Grimmer (MIT license).
-
-Embeds [stb_textedit.h, stb_truetype.h, stb_rectpack.h](https://github.com/nothings/stb/) by Sean Barrett (public domain).
-
-Inspiration, feedback, and testing for early versions: Casey Muratori, Atman Binstock, Mikko Mononen, Emmanuel Briney, Stefan Kamoda, Anton Mikhailov, Matt Willis. And everybody posting feedback, questions and patches on the GitHub.
-
-License
--------
-
-Dear ImGui is licensed under the MIT License, see LICENSE for more information.

Source/ThirdParty/ImGuiLibrary/TODO.txt

@@ -1,315 +0,0 @@
-dear imgui
-ISSUES & TODO LIST
-
-Issue numbers (#) refer to github issues listed at https://github.com/ocornut/imgui/issues/XXXX
-The list below consist mostly of ideas noted down before they are requested/discussed by users (at which point they usually exist on the github issue tracker).
-It's mostly a bunch of personal notes, probably incomplete. Feel free to query if you have any questions.
-
- - doc/test: add a proper documentation+regression testing system (#435)
- - doc/test: checklist app to verify binding/integration of imgui (test inputs, rendering, callback, etc.).
- - doc/tips: tips of the day: website? applet in imgui_club?
- - project: folder or separate repository with maintained helpers (e.g. imgui_memory_editor.h, imgui_stl.h, maybe imgui_dock would be there?)
-
- - window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
- - window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
- - window: auto-fit feedback loop when user relies on any dynamic layout (window width multiplier, column) appears weird to end-user. clarify.
- - window: allow resizing of child windows (possibly given min/max for each axis?.)
- - window: background options for child windows, border option (disable rounding).
- - window: resizing from any sides? done. > need backends to honor mouse cursors properly. (#822)
- - window: resize from borders: support some form of outer padding to make it easier to grab borders. (#822)
- - window: fix resize glitch when collapsing an AlwaysAutoResize window.
- - window: begin with *p_open == false could return false.
- - window: get size/pos helpers given names (see discussion in #249)
- - window: a collapsed window can be stuck behind the main menu bar?
- - window: when window is very small, prioritize resize button over close button.
- - window: detect extra End() call that pop the "Debug" window out and assert at End() call site instead of at end of frame.
- - window: increase minimum size of a window with menus or fix the menu rendering so that it doesn't look odd.
- - window: double-clicking on title bar to minimize isn't consistent, perhaps move to single-click on left-most collapse icon?
- - window: expose contents size. (#1045)
- - window: using SetWindowPos() inside Begin() and moving the window with the mouse reacts a very ugly glitch. We should just defer the SetWindowPos() call.
- - window: GetWindowSize() returns (0,0) when not calculated? (#1045)
- - window: freeze window flag: if not focused/hovered, return false, render with previous ImDrawList. and/or reduce refresh rate. 
- - window: investigate better auto-positioning for new windows.
- - scrolling: allow immediately effective change of scroll after Begin() if we haven't appended items yet.
- - scrolling/clipping: separator on the initial position of a window is not visible (cursorpos.y <= clippos.y). (2017-08-20: can't repro)
- - scrolling/style: shadows on scrollable areas to denote that there is more contents
-
- - drawdata: make it easy to clone (or swap?) a ImDrawData so user can easily save that data if they use threaded rendering.
- - drawlist: end-user probably can't call Clear() directly because we expect a texture to be pushed in the stack.
- - drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command).
- - drawlist: primitives/helpers to manipulate vertices post submission, so e.g. a quad/rect can be resized to fit later submitted content, _without_ using the ChannelSplit api
- - drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
- - drawlist: non-AA strokes have gaps between points (#593, #288), especially RenderCheckmark().
- - drawlist: would be good to be able to deep copy of ImDrawData (we have a deep copy of ImDrawList now).
- - drawlist: rendering: provide a way for imgui to output to a single/global vertex buffer, re-order indices only at the end of the frame (ref: https://gist.github.com/floooh/10388a0afbe08fce9e617d8aefa7d302)
- - drawlist: callback: add an extra void* in ImDrawCallback to allow passing render-local data to the callback (would break API).
- - drawlist/opt: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding. (#1962)
- - drawlist/opt: AddRect() axis aligned pixel aligned (no-aa) could use 8 triangles instead of 16 and no normal calculation.
-
- - main: considering adding an Init() function? some constructs are awkward in the implementation because of the lack of them.
- - main: find a way to preserve relative orders of multiple reappearing windows (so an app toggling between "modes" e.g. fullscreen vs all tools) won't lose relative ordering.
- - main: IsItemHovered() make it more consistent for various type of widgets, widgets with multiple components, etc. also effectively IsHovered() region sometimes differs from hot region, e.g tree nodes
- - main: IsItemHovered() info stored in a stack? so that 'if TreeNode() { Text; TreePop; } if IsHovered' return the hover state of the TreeNode?
- - main: rename the main "Debug" window to avoid ID collision with user who may want to use "Debug" with specific flags.
-
- - widgets: display mode: widget-label, label-widget (aligned on column or using fixed size), label-newline-tab-widget etc. (#395)
- - widgets: clean up widgets internal toward exposing everything and stabilizing imgui_internals.h.
- - widgets: add visuals for Disabled/ReadOnly mode and expose publicly (#211)
- - widgets: add always-allow-overlap mode.
- - widgets: start exposing PushItemFlag() and ImGuiItemFlags
- - widgets: alignment options in style (e.g. center Selectable, Right-Align within Button, etc.) #1260
- - widgets: activate by identifier (trigger button, focus given id)
- - widgets: a way to represent "mixed" values, so e.g. all values replaced with **, including check-boxes, colors, etc. with support for multi-components widgets (e.g. SliderFloat3, make only "Y" mixed)
-
- - input text: clean up the mess caused by converting UTF-8 <> wchar. the code is rather inefficient right now and super fragile. 
- - input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
- - input text: expose CursorPos in char filter event (#816)
- - input text: access public fields via a non-callback API e.g. InputTextGetState("xxx") that may return NULL if not active.
- - input text: flag to disable live update of the user buffer (also applies to float/int text input) (#701)
- - input text: hover tooltip could show unclamped text
- - input text: option to Tab after an Enter validation.
- - input text: add ImGuiInputTextFlags_EnterToApply? (off #218)
- - input text: easier ways to update buffer (from source char*) while owned. preserve some sort of cursor position for multi-line text.
- - input text: add discard flag (e.g. ImGuiInputTextFlags_DiscardActiveBuffer) or make it easier to clear active focus for text replacement during edition (#725)
- - input text: display bug when clicking a drag/slider after an input text in a different window has all-selected text (order dependent). actually a very old bug but no one appears to have noticed it.
- - input text: allow centering/positioning text so that ctrl+clicking Drag or Slider keeps the textual value at the same pixel position.
- - input text: what's the easiest way to implement a nice IP/Mac address input editor?
- - input text multi-line: don't directly call AddText() which does an unnecessary vertex reserve for character count prior to clipping. and/or more line-based clipping to AddText(). and/or reorganize TextUnformatted/RenderText for more efficiency for large text (e.g TextUnformatted could clip and log separately, etc).
- - input text multi-line: support for cut/paste without selection (cut/paste the current line)
- - input text multi-line: line numbers? status bar? (follow up on #200)
- - input text multi-line: behave better when user changes input buffer while editing is active (even though it is illegal behavior). namely, the change of buffer can create a scrollbar glitch (#725)
- - input text multi-line: better horizontal scrolling support (#383, #1224)
- - input text multi-line: single call to AddText() should be coarse clipped on InputTextEx() end.
- - input number: optional range min/max for Input*() functions
- - input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
- - input number: use mouse wheel to step up/down
- - input number: applying arithmetics ops (+,-,*,/) messes up with text edit undo stack.
-
- - layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
- - layout: generalization of the above: a concept equivalent to word processor ruler tab stop ~ mini columns (position in X, no clipping implied) (vaguely relate to #267, #395, also what is used internally for menu items)
- - layout: horizontal layout helper (#97)
- - layout: horizontal flow until no space left (#404)
- - layout: more generic alignment state (left/right/centered) for single items?
- - layout: clean up the InputFloatN/SliderFloatN/ColorEdit4 layout code. item width should include frame padding.
- - layout: BeginGroup() needs a border option. (~#1496)
- - layout: vertical alignment of mixed height items (e.g. buttons) within a same line (#1284)
- 
- - columns: sizing policy (e.g. for each column: fixed size, %, fill, distribute default size among fills) (#513, #125)
- - columns: add a conditional parameter to SetColumnOffset() (#513, #125)
- - columns: headers. reorderable. (#513, #125)
- - columns: optional sorting modifiers (up/down), sort list so sorting can be done multi-criteria. notify user when sort order changed.
- - columns: option to alternate background colors on odd/even scanlines.  
- - columns: allow columns to recurse. 
- - columns: allow a same columns set to be interrupted by e.g. CollapsingHeader and resume with columns in sync when moving them. 
- - columns: separator function or parameter that works within the column (currently Separator() bypass all columns) (#125)
- - columns: flag to add horizontal separator above/below?
- - columns/layout: setup minimum line height (equivalent of automatically calling AlignFirstTextHeightToWidgets)
-
-!- color: the color conversion helpers/types are a mess and needs sorting out. 
- - color: (api breaking) ImGui::ColorConvertXXX functions should be loose ImColorConvertXX to match imgui_internals.h
-
- - plot: full featured plot/graph api w/ scrolling, zooming etc. all bell & whistle. why not!
- - plot: PlotLines() should use the polygon-stroke facilities, less vertices (currently issues with averaging normals)
- - plot: make it easier for user to draw extra stuff into the graph (e.g: draw basis, highlight certain points, 2d plots, multiple plots)
- - plot: "smooth" automatic scale over time, user give an input 0.0(full user scale) 1.0(full derived from value)
- - plot: option/feature: draw the zero line
- - plot: option/feature: draw grid, vertical markers
- - plot: option/feature: draw unit
- - plot: add a helper e.g. Plot(char* label, float value, float time_span=2.0f) that stores values and Plot them for you - probably another function name. and/or automatically allow to plot ANY displayed value (more reliance on stable ID)
-
- - clipper: ability to force display 1 item in the list would be convenient (for patterns where we need to set active id etc.)
- - clipper: ability to disable the clipping through a simple flag/bool.
- - clipper: ability to run without knowing full count in advance.
-
- - splitter/separator: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)
- 
- - dock: docking extension
- - dock: dock out from a collapsing header? would work nicely but need emitting window to keep submitting the code.
-
- - tabs: re-ordering, close buttons, context menu, persistent order (#261, #351)
-
- - ext: stl-ish friendly extension (imgui_stl.h) that has wrapper for std::string, std::vector etc.
-
- - button: provide a button that looks framed.
- - image/image button: misalignment on padded/bordered button?
- - image/image button: parameters are confusing, image() has tint_col,border_col whereas imagebutton() has bg_col/tint_col. Even thou they are different parameters ordering could be more consistent. can we fix that?
- - image button: not taking an explicit id is odd.
- - slider: allow using the [-]/[+] buttons used by InputFloat()/InputInt()
- - slider: initial absolute click is imprecise. change to relative movement slider (same as scrollbar). (#1946)
- - slider: add dragging-based widgets to edit values with mouse (on 2 axises), saving screen real-estate.
- - slider: tint background based on value (e.g. v_min -> v_max, or use 0.0f either side of the sign)
- - slider: relative dragging? + precision dragging
- - slider: step option (#1183)
- - slider style: fill % of the bar instead of positioning a drag.
- - knob: rotating knob widget (#942)
- - drag float: up/down axis
- - drag float: added leeway on edge (e.g. a few invisible steps past the clamp limits)
-
- - combo: use clipper: make it easier to disable clipper with a single flag.
- - combo: flag for BeginCombo to not return true when unchanged (#1182)
- - combo: a way/helper to customize the combo preview (#1658)
- - combo/listbox: keyboard control. need InputText-like non-active focus + key handling. considering keyboard for custom listbox (pr #203)
- - listbox: refactor and clean the begin/end api
- - listbox: multiple selection.
- - listbox: unselect option (#1208)
- - listbox: make it easier/more natural to implement range-select (need some sort of info/ref about the last clicked/focused item that user can translate to an index?) (wip stash)
- - listbox: user may want to initial scroll to focus on the one selected value?
- - listbox: expose hovered item for a basic ListBox
- - listbox: keyboard navigation.
- - listbox: scrolling should track modified selection.
-
-!- popups/menus: clarify usage of popups id, how MenuItem/Selectable closing parent popups affects the ID, etc. this is quite fishy needs improvement! (#331, #402)
- - popups/modal: make modal title bar blink when trying to click outside the modal
- - popups: reopening context menu at new position should be the behavior by default? (equivalent to internal OpenPopupEx() with reopen_existing=true) (~#1497)
- - popups: if the popup functions took explicit ImGuiID it would allow the user to manage the scope of those ID. (#331)
- - popups: clicking outside (to close popup) and holding shouldn't drag window below.
- - popups: add variant using global identifier similar to Begin/End (#402)
- - popups: border options. richer api like BeginChild() perhaps? (#197)
- - tooltip: drag and drop with tooltip near monitor edges lose/changes its last direction instead of locking one. The drag and drop tooltip should always follow without changing direction.
- - tooltip: tooltip that doesn't fit in entire screen seems to lose their "last preferred direction" and may teleport when moving mouse.
- - tooltip: allow to set the width of a tooltip to allow TextWrapped() etc. while keeping the height automatic.
- - tooltip: tooltips with delay timers? or general timer policy? (instantaneous vs timed): IsItemHovered() with timer + implicit aabb-id for items with no ID. (#1485) 
- 
- - menus: calling BeginMenu() twice with a same name doesn't append as Begin() does for regular windows (#1207)
- - menus: menu bars inside modal windows are acting weird.
- - status-bar: add a per-window status bar helper similar to what menu-bar does.
- - shortcuts: local-style shortcut api, e.g. parse "&Save"
- - shortcuts,menus: global-style shortcut api e.g. "Save (CTRL+S)" -> explicit flag for recursing into closed menu
- - shortcuts: programmatically access shortcuts "Focus("&Save"))
- - menus: menu-bar: main menu-bar could affect clamping of windows position (~ akin to modifying DisplayMin)
- - menus: hovering from menu to menu on a menu-bar has 1 frame without any menu, which is a little annoying. ideally either 0 either longer. 
-
- - text: selectable text (for copy) as a generic feature (ItemFlags?)
- - text: proper alignment options in imgui_internal.h
- - text wrapped: figure out better way to use TextWrapped() in an always auto-resize context (tooltip, etc.) (#249)
- - text: it's currently impossible to have a window title with "##". perhaps an official workaround would be nice. \ style inhibitor? non-visible ascii code to insert between #?
- - text: provided a framed text helper, e.g. https://pastebin.com/1Laxy8bT
- - text link/url button: underlined. should api expose an ID or use text contents as ID? which colors enum to use?
-
- - tree node / optimization: avoid formatting when clipped.
- - tree node: tree-node/header right-most side doesn't take account of horizontal scrolling.
- - tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
- - tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?
- - tree node / selectable render mismatch which is visible if you use them both next to each other (e.g. cf. property viewer)
- - tree node: tweak color scheme to distinguish headers from selected tree node (#581)
- - tree node: leaf/non-leaf highlight mismatch.
-
- - settings: write more decent code to allow saving/loading new fields: columns, selected tree nodes?
- - settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
- - stb: add defines to disable stb implementations
-
-!- style: better default styles. (#707)
- - style: add a highlighted text color (for headers, etc.)
- - style: border types: out-screen, in-screen, etc. (#447)
- - style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
- - style: a concept of "compact style" that the end-user can easily rely on (e.g. PushStyleCompact()?) that maps to other settings? avoid implementing duplicate helpers such as SmallCheckbox(), etc.
- - style: try to make PushStyleVar() more robust to incorrect parameters (to be more friendly to edit & continues situation).
- - style: global scale setting.
- - style: WindowPadding needs to be EVEN as the 0.5 multiplier used on this value probably have a subtle effect on clip rectangle
- - style: have a more global HSV setter (e.g. alter hue on all elements). consider replacing active/hovered by offset in HSV space? (#438, #707, #1223)
- - style: gradients fill (#1223) ~ 2 bg colors for each fill? tricky with rounded shapes and using textures for corners.
- - style editor: color child window height expressed in multiple of line height.
-
- - log: LogButtons() options for specifying depth and/or hiding depth slider
- - log: have more control over the log scope (e.g. stop logging when leaving current tree node scope)
- - log: be able to log anything (e.g. right-click on a window/tree-node, shows context menu? log into tty/file/clipboard)
- - log: let user copy any window content to clipboard easily (CTRL+C on windows? while moving it? context menu?). code is commented because it fails with multiple Begin/End pairs.
-
- - filters: set a current filter that tree node can automatically query to hide themselves
- - filters: handle wild-cards (with implicit leading/trailing *), reg-exprs
- - filters: fuzzy matches (may use code at blog.forrestthewoods.com/4cffeed33fdb)
-
- - drag and drop: have some way to know when a drag begin from BeginDragDropSource() pov.
- - drag and drop: allow preview tooltip to be submitted from a different place than the drag source. (#1725)
- - drag and drop: allow using with other mouse buttons (where activeid won't be set). (#1637)
- - drag and drop: make it easier and provide a demo to have tooltip both are source and target site, with a more detailed one on target site (tooltip ordering problem)
- - drag and drop: test with reordering nodes (in a list, or a tree node). (#143)
- - drag and drop: test integrating with os drag and drop (make it easy to do a naive WM_DROPFILE integration)
- - drag and drop: make payload optional? (#143)
- - drag and drop: feedback when hovering a modal (cursor?)
- - node/graph editor (#306)
- - pie menus patterns (#434)
- - markup: simple markup language for color change? (#902)
-
-!- font: need handling of missing glyphs by not packing/rasterizing glyph 0 of a given font.
- - font: MergeMode: flags to select overwriting or not.
- - font: MergeMode: duplicate glyphs are stored in the atlas texture which is suboptimal.
- - font: free the Alpha buffer if user only requested RGBA.
-!- font: better CalcTextSizeA() API, at least for simple use cases. current one is horrible (perhaps have simple vs extended versions).
- - font: a CalcTextHeight() helper could run faster than CalcTextSize().y
- - font: enforce monospace through ImFontConfig (for icons?) + create dual ImFont output from same input, reusing rasterized data but with different glyphs/AdvanceX
- - font: finish CustomRectRegister() to allow mapping Unicode codepoint to custom texture data 
- - font: PushFontSize API (#1018)
- - font: MemoryTTF taking ownership confusing/not obvious, maybe default should be opposite?
- - font/atlas: add a missing Glyphs.reserve()
- - font/atlas: incremental updates
- - font/atlas: dynamic font atlas to avoid baking huge ranges into bitmap and make scaling easier.
- - font/atlas: allow user to submit its own primitive to be rectpacked, and allow to map them on a Unicode point.
- - font/draw: vertical and/or rotated text renderer (#705) - vertical is easier clipping wise
- - font/draw: need to be able to specify wrap start position.
- - font/draw: better reserve policy for large horizontal block of text (shouldn't reserve for all clipped lines)
- - font: imgui_freetype.h alternative renderer (#618)
- - font: optimization: for monospace font (like the default one) we can trim IndexXAdvance as long as trailing value is == FallbackXAdvance (need to make sure TAB is still correct).
- - font: add support for kerning, probably optional. A) perhaps default to (32..128)^2 matrix ~ 9K entries = 36KB, then hash for non-ascii?. B) or sparse lookup into per-char list?
- - font: add a simpler CalcTextSizeA() api? current one ok but not welcome if user needs to call it directly (without going through ImGui::CalcTextSize)
- - font: fix AddRemapChar() to work before font has been built.
- - font: (api breaking) removed "TTF" from symbol names. also because it now supports OTF.
-
- - nav: wrap around logic to allow e.g. grid based layout (pressing NavRight on the right-most element would go to the next row, etc.). see internal's NavMoveRequestTryWrapping().
- - nav: patterns to make it possible for arrows key to update selection
- - nav: restore/find nearest navid when current one disappear (e.g. pressed a button that disappear, or perhaps auto restoring when current button change name)
- - nav: SetItemDefaultFocus() level of priority, so widget like Selectable when inside a popup could claim a low-priority default focus on the first selected iem
- - nav: allow input system to be be more tolerant of io.DeltaTime=0.0f
- - nav: ESC within a menu of a child window seems to exit the child window.
- - nav: NavFlattened: ESC on a flattened child should select something.
- - nav: NavFlattened: broken: in typical usage scenario, the items of a fully clipped child are currently not considered to enter into a NavFlattened child.
- - nav: NavFlattened: init request doesn't select items that are part of a NavFlattened child
- - nav: NavFlattened: cannot access menu-bar of a flattened child window with Alt/menu key (not a very common use case..).
- - nav: Left within a tree node block as a fallback (ImGuiTreeNodeFlags_NavLeftJumpsBackHere by default?)
- - nav: menus: pressing left-right on a vertically clipped menu bar tends to jump to the collapse/close buttons.
- - nav: menus: allow pressing Menu to leave a sub-menu.
- - nav: simulate right-click or context activation? (SHIFT+F10)
- - nav: tabs should go through most/all widgets (in submission order?).
- - nav: when CTRL-Tab/windowing is active, the HoveredWindow detection doesn't take account of the window display re-ordering.
- - nav: esc/enter default behavior for popups, e.g. be able to mark an "ok" or "cancel" button that would get triggered by those keys.
- - nav: when activating a button that changes label (without a static ID) or disappear, can we somehow automatically recover into a nearest highlight item?
- - nav: there's currently no way to completely clear focus with the keyboard. depending on patterns used by the application to dispatch inputs, it may be desirable.
- - nav: configuration flag to disable global shortcuts (currently only CTRL-tab) ?
- - focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
- - focus: SetKeyboardFocusHere() on with >= 0 offset could be done on same frame (else latch and modulate on beginning of next frame)
- - focus: unable to use SetKeyboardFocusHere() on clipped widgets. (#787)
-
- - inputs: we need an explicit flag about whether the imgui window is focused, to be able to distinguish focused key releases vs alt-tabbing all release behaviors.
- - inputs: rework IO system to be able to pass actual ordered/timestamped events. use an event queue? (~#335, #71)
- - inputs: support track pad style scrolling & slider edit.
- - inputs/io: backspace and arrows in the context of a text input could use system repeat rate.
- - inputs/io: clarify/standardize/expose repeat rate and repeat delays (#1808)
-
- - misc: idle refresh: expose cursor blink animation timer for backend to be able to lower framerate.
- - misc: make the ImGuiCond values linear (non-power-of-two). internal storage for ImGuiWindow can use integers to combine into flags (Why?)
- - misc: provide a way to compile out the entire implementation while providing a dummy API (e.g. #define IMGUI_DUMMY_IMPL)
- - misc: PushItemFlag(): add a flag to disable keyboard capture when used with mouse? (#1682)
- - misc: use more size_t in public api?
- - misc: ImVector: erase_unsorted() helper
- - misc: imgui_cpp: perhaps a misc/ header file with more friendly helper (e.g. type-infer versions of DragScalar, vector<> variants if appropriate for some functions).
-
- - backend: bgfx? https://gist.github.com/RichardGale/6e2b74bc42b3005e08397236e4be0fd0
- - web/emscriptem: refactor some examples to facilitate integration with emscripten main loop system. (#1713, #336)
- - web/emscriptem: with refactored examples, we could provide a direct imgui_impl_emscripten platform layer (see eg. https://github.com/floooh/sokol-samples/blob/master/html5/imgui-emsc.cc#L42)
-
- - remote: make a system like RemoteImGui first-class citizen/project (#75)
-
- - demo: find a way to demonstrate textures in the examples application, as it such a a common issue for new users.
- - demo: add vertical separator demo
- - demo: add virtual scrolling example?
- - demo: demonstration Plot offset
- - examples: window minimize, maximize (#583)
- - examples: provide a zero frame-rate/idle example.
- - examples: apple: example_apple should be using modern GL3.
- - examples: glfw: could go idle when minimized? if (glfwGetWindowAttrib(window, GLFW_ICONIFIED)) { glfwWaitEvents(); continue; } // issue: DeltaTime will be super high on resume, perhaps provide a way to let impl know (#440)
- - optimization: replace vsnprintf with stb_printf? or enable the defines/infrastructure to allow it (#1038)
- - optimization: add clipping for multi-component widgets (SliderFloatX, ColorEditX, etc.). one problem is that nav branch can't easily clip parent group when there is a move request.
- - optimization: add a flag to disable most of rendering, for the case where the user expect to skip it (#335)
- - optimization: use another hash function than crc32, e.g. FNV1a
- - optimization/render: merge command-lists with same clip-rect into one even if they aren't sequential? (as long as in-between clip rectangle don't overlap)?
- - optimization: turn some the various stack vectors into statically-sized arrays