void DrawRectangle(
float X,
float Y,
float SizeX,
float SizeY,
float U,
float V,
float SizeU,
float SizeV,
FIntPoint TargetSize,
FIntPoint TextureSize,
EDrawRectangleFlags Flags
)
{
float ClipSpaceQuadZ = 0.0f;
DoDrawRectangleFlagOverride(Flags);
// triangle if extending to left and top of the given rectangle, if it's not left top of the viewport it can cause artifacts
if(X > 0.0f || Y > 0.0f)
{
// don't use triangle optimization
Flags = EDRF_Default;
}
if (Flags == EDRF_UseTriangleOptimization)
{
// A single triangle spans the entire viewport this results in a quad that fill the viewport. This can increase rasterization efficiency
// as we do not have a diagonal edge (through the center) for the rasterizer/span-dispatch. Although the actual benefit of this technique is dependent upon hardware.
FFilterVertex Vertices[3];
Vertices[0].Position = FVector4(X + SizeX, Y - SizeY, ClipSpaceQuadZ, 1);
Vertices[1].Position = FVector4(X + SizeX, Y + SizeY, ClipSpaceQuadZ, 1);
Vertices[2].Position = FVector4(X - SizeX, Y + SizeY , ClipSpaceQuadZ, 1);
Vertices[0].UV = FVector2D(U + SizeU, V - SizeV);
Vertices[1].UV = FVector2D(U + SizeU, V + SizeV);
Vertices[2].UV = FVector2D(U - SizeU, V + SizeV);
for (int32 VertexIndex = 0; VertexIndex < 3; VertexIndex++)
{
Vertices[VertexIndex].Position.X = -1.0f + 2.0f * (Vertices[VertexIndex].Position.X - GPixelCenterOffset) / (float)TargetSize.X;
Vertices[VertexIndex].Position.Y = (+1.0f - 2.0f * (Vertices[VertexIndex].Position.Y - GPixelCenterOffset) / (float)TargetSize.Y) * GProjectionSignY;
Vertices[VertexIndex].UV.X = Vertices[VertexIndex].UV.X / (float)TextureSize.X;
Vertices[VertexIndex].UV.Y = Vertices[VertexIndex].UV.Y / (float)TextureSize.Y;
}
static const uint16 Indices[] = { 0, 1, 2 };
RHIDrawIndexedPrimitiveUP(PT_TriangleList, 0, 3, 1, Indices, sizeof(Indices[0]), Vertices, sizeof(Vertices[0]));
}
else
{
FFilterVertex Vertices[4];
Vertices[0].Position = FVector4(X, Y, ClipSpaceQuadZ, 1);
Vertices[1].Position = FVector4(X + SizeX, Y, ClipSpaceQuadZ, 1);
Vertices[2].Position = FVector4(X, Y + SizeY, ClipSpaceQuadZ, 1);
Vertices[3].Position = FVector4(X + SizeX, Y + SizeY, ClipSpaceQuadZ, 1);
Vertices[0].UV = FVector2D(U, V);
Vertices[1].UV = FVector2D(U + SizeU, V);
Vertices[2].UV = FVector2D(U, V + SizeV);
Vertices[3].UV = FVector2D(U + SizeU, V + SizeV);
for (int32 VertexIndex = 0; VertexIndex < 4; VertexIndex++)
{
Vertices[VertexIndex].Position.X = -1.0f + 2.0f * (Vertices[VertexIndex].Position.X - GPixelCenterOffset) / (float)TargetSize.X;
Vertices[VertexIndex].Position.Y = (+1.0f - 2.0f * (Vertices[VertexIndex].Position.Y - GPixelCenterOffset) / (float)TargetSize.Y) * GProjectionSignY;
Vertices[VertexIndex].UV.X = Vertices[VertexIndex].UV.X / (float)TextureSize.X;
Vertices[VertexIndex].UV.Y = Vertices[VertexIndex].UV.Y / (float)TextureSize.Y;
}
static const uint16 Indices[] = { 0, 1, 3, 0, 3, 2 };
RHIDrawIndexedPrimitiveUP(PT_TriangleList, 0, 4, 2, Indices, sizeof(Indices[0]), Vertices, sizeof(Vertices[0]));
}
}
void DrawRectangle(
FRHICommandList& RHICmdList,
float X,
float Y,
float SizeX,
float SizeY,
float U,
float V,
float SizeU,
float SizeV,
FIntPoint TargetSize,
FIntPoint TextureSize,
FShader* VertexShader,
EDrawRectangleFlags Flags
)
{
float ClipSpaceQuadZ = 0.0f;
DoDrawRectangleFlagOverride(Flags);
// triangle if extending to left and top of the given rectangle, if it's not left top of the viewport it can cause artifacts
if(X > 0.0f || Y > 0.0f)
{
// don't use triangle optimization
Flags = EDRF_Default;
}
// Set up vertex uniform parameters for scaling and biasing the rectangle.
// Note: Use DrawRectangle in the vertex shader to calculate the correct vertex position and uv.
FDrawRectangleParameters Parameters;
Parameters.PosScaleBias = FVector4(SizeX, SizeY, X, Y);
Parameters.UVScaleBias = FVector4(SizeU, SizeV, U, V);
Parameters.InvTargetSizeAndTextureSize = FVector4(
1.0f / TargetSize.X, 1.0f / TargetSize.Y,
1.0f / TextureSize.X, 1.0f / TextureSize.Y);
SetUniformBufferParameterImmediate(RHICmdList, VertexShader->GetVertexShader(), VertexShader->GetUniformBufferParameter<FDrawRectangleParameters>(), Parameters);
if(Flags == EDRF_UseTesselatedIndexBuffer)
{
// no vertex buffer needed as we compute it in VS
RHICmdList.SetStreamSource(0, NULL, 0, 0);
RHICmdList.DrawIndexedPrimitive(
GTesselatedScreenRectangleIndexBuffer.IndexBufferRHI,
PT_TriangleList,
/*BaseVertexIndex=*/ 0,
/*MinIndex=*/ 0,
/*NumVertices=*/ GTesselatedScreenRectangleIndexBuffer.NumVertices(),
/*StartIndex=*/ 0,
/*NumPrimitives=*/ GTesselatedScreenRectangleIndexBuffer.NumPrimitives(),
/*NumInstances=*/ 1
);
}
else
{
RHICmdList.SetStreamSource(0, GScreenRectangleVertexBuffer.VertexBufferRHI, sizeof(FFilterVertex), 0);
if (Flags == EDRF_UseTriangleOptimization)
{
// A single triangle spans the entire viewport this results in a quad that fill the viewport. This can increase rasterization efficiency
// as we do not have a diagonal edge (through the center) for the rasterizer/span-dispatch. Although the actual benefit of this technique is dependent upon hardware.
// We offset into the index buffer when using the triangle optimization to access the correct vertices.
RHICmdList.DrawIndexedPrimitive(
GScreenRectangleIndexBuffer.IndexBufferRHI,
PT_TriangleList,
/*BaseVertexIndex=*/ 0,
/*MinIndex=*/ 0,
/*NumVertices=*/ 3,
/*StartIndex=*/ 6,
/*NumPrimitives=*/ 1,
/*NumInstances=*/ 1
);
}
else
{
RHICmdList.SetStreamSource(0, GScreenRectangleVertexBuffer.VertexBufferRHI, sizeof(FFilterVertex), 0);
RHICmdList.DrawIndexedPrimitive(
GScreenRectangleIndexBuffer.IndexBufferRHI,
PT_TriangleList,
/*BaseVertexIndex=*/ 0,
/*MinIndex=*/ 0,
/*NumVertices=*/ 4,
/*StartIndex=*/ 0,
/*NumPrimitives=*/ 2,
/*NumInstances=*/ 1
);
}
}
}
