UnrealImGui/Source/ImGui/Private/ImGuiDrawData.cpp
Sebastian 35f2d342a0 Added support for ImGui context update and rendering:
- Added ImGui Module Manager that that implements module logic and manages other module resources.
- Added Texture Manager to manage texture resources and maps them to index that can be passed to ImGui context.
- Added Context Proxy that represents and manages a single ImGui context.
- Added Slate ImGui Widget to render ImGui output.
2017-03-26 21:32:57 +01:00

60 lines
2.1 KiB
C++

// Distributed under the MIT License (MIT) (see accompanying LICENSE file)
#include "ImGuiPrivatePCH.h"
#include "ImGuiDrawData.h"
void FImGuiDrawList::CopyVertexData(TArray<FSlateVertex>& OutVertexBuffer, const FVector2D VertexPositionOffset, const FSlateRotatedRect& VertexClippingRect) const
{
// Reset and reserve space in destination buffer.
OutVertexBuffer.SetNumUninitialized(ImGuiVertexBuffer.Size, false);
// Transform and copy vertex data.
for (int Idx = 0; Idx < ImGuiVertexBuffer.Size; Idx++)
{
const ImDrawVert& ImGuiVertex = ImGuiVertexBuffer[Idx];
FSlateVertex& SlateVertex = OutVertexBuffer[Idx];
// Final UV is calculated in shader as XY * ZW, so we need set all components.
SlateVertex.TexCoords[0] = ImGuiVertex.uv.x;
SlateVertex.TexCoords[1] = ImGuiVertex.uv.y;
SlateVertex.TexCoords[2] = SlateVertex.TexCoords[3] = 1.f;
// Copy ImGui position and add offset.
SlateVertex.Position[0] = ImGuiVertex.pos.x + VertexPositionOffset.X;
SlateVertex.Position[1] = ImGuiVertex.pos.y + VertexPositionOffset.Y;
// Set clipping rectangle.
SlateVertex.ClipRect = VertexClippingRect;
// Unpack ImU32 color.
SlateVertex.Color = ImGuiInterops::UnpackImU32Color(ImGuiVertex.col);
}
}
void FImGuiDrawList::CopyIndexData(TArray<SlateIndex>& OutIndexBuffer, const int32 StartIndex, const int32 NumElements) const
{
// Reset buffer.
OutIndexBuffer.SetNumUninitialized(NumElements, false);
// Copy elements (slow copy because of different sizes of ImDrawIdx and SlateIndex and because SlateIndex can
// have different size on different platforms).
for (int i = 0; i < NumElements; i++)
{
OutIndexBuffer[i] = ImGuiIndexBuffer[StartIndex + i];
}
}
void FImGuiDrawList::TransferDrawData(ImDrawList& Src)
{
// Move data from source to this list.
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();
}