Fix Z-fighting issues in Debug Draw when using TAA

Source/Engine/Debug/DebugDraw.cpp

@@ -127,7 +127,8 @@ PACK_STRUCT(struct Vertex {
 
 PACK_STRUCT(struct Data {
     Matrix ViewProjection;
-    Float3 Padding;
+    Float2 Padding;
+    float ClipPosZBias;
     bool EnableDepthTest;
     });
 
@@ -785,6 +786,7 @@ void DebugDraw::Draw(RenderContext& renderContext, GPUTextureView* target, GPUTe
     Matrix vp;
     Matrix::Multiply(view.View, view.Projection, vp);
     Matrix::Transpose(vp, data.ViewProjection);
+    data.ClipPosZBias = -0.2f; // Reduce Z-fighting artifacts (eg. editor grid)
     data.EnableDepthTest = enableDepthTest;
     context->UpdateCB(cb, &data);
     context->BindCB(0, cb);

Source/Shaders/DebugDraw.shader

@@ -4,7 +4,8 @@
 
 META_CB_BEGIN(0, Data)
 float4x4 ViewProjection;
-float3 Padding;
+float2 Padding;
+float ClipPosZBias;
 bool EnableDepthTest;
 META_CB_END
 
@@ -23,6 +24,7 @@ VS2PS VS(float3 Position : POSITION, float4 Color : COLOR)
 {
 	VS2PS output;
 	output.Position = mul(float4(Position, 1), ViewProjection);
+	output.Position.z += ClipPosZBias;
 	output.Color = Color;
 	return output;
 }