CodeLog

// - Create RDG texture demonstration ----
 // Create RDG texture description
FRDGTextureDesc TextureDesc = Input.Texture->Desc;
TextureDesc.Reset();
TextureDesc.Format = PF_FloatRGBA;
TextureDesc.ClearValue = FClearValueBinding::None;
TextureDesc.Flags &= ~TexCreate_DepthStencilTargetable;
TextureDesc.Flags |= TexCreate_RenderTargetable;
TextureDesc.Extent = OutputViewport.Extent;
 // Create RDG texture.
FRDGTextureRef MyRDGTexture = GraphBuilder.CreateTexture(TextureDesc, TEXT("MyRDGTexture"));

 // ---- Create RDG Texture UAV Demonstration ----
FRDGTextureUAVRef MyRDGTextureUAV = GraphBuilder.CreateUAV(MyRDGTexture);

 // ---- Create RDG texture SRV demonstration ----
FRDGTextureSRVRef MyRDGTextureSRV = GraphBuilder.CreateSRV(FRDGTextureSRVDesc::CreateWithPixelFormat(MyRDGTexture, PF_FloatRGBA));

// Create a RHI resource outside RDG.
FRHIResourceCreateInfo CreateInfo;
FTexture2DRHIRef MyRHITexture = RHICreateTexture2D(1024, 768, PF_B8G8R8A8, 1, 1, TexCreate_CPUReadback, CreateInfo);

 // Register an external RHI resource to RDG resources.
FRDGTextureRef MyExternalRDGTexture = GraphBuilder.RegisterExternalTexture(MyRHITexture);

// Create a Pass's Shader parameter.
FMyPS::FParameters* PassParameters = GraphBuilder.AllocParameters<FMyPS::FParameters>();
PassParameters->InputTexture = InputTexture;
PassParameters->RenderTargets = FRenderTargetBinding(InputTexture, InputTextureLoadAction);
PassParameters->InputSampler = BilinearSampler;

 // Treat the shader.
TShaderMapRef<FScreenPassVS> VertexShader(View.ShaderMap);
TShaderMapRef<FMyPS> PixelShader(View.ShaderMap);

const FScreenPassPipelineState PipelineState(VertexShader, PixelShader, AdditiveBlendState);

 // Add RDG Pass.
GraphBuilder.AddPass(
    RDG_EVENT_NAME("MyRDGPass"),
    PassParameters,
    ERDGPassFlags::Raster,
         // pas of Lambda
    [PixelShader, PassParameters, PipelineState] (FRHICommandListImmediate& RHICmdList)
    {
                 // Set the viewport.
        RHICmdList.SetViewport(0, 0, 0.0f, 1024, 768, 1.0f);

                 // Set PSO.
        SetScreenPassPipelineState(RHICmdList, PipelineState);

                 // Set shader parameters.
        SetShaderParameters(RHICmdList, PixelShader, PixelShader.GetPixelShader(), *PassParameters);

                 // Draw a rectangular area.
        DrawRectangle(RHICmdList, 0, 0, 1024, 768, 0, 0, 1.0f, 1.0f, FIntPoint(1024, 768), FIntPoint(1024, 768), PipelineState.VertexShader, EDRF_Default);
    });

void RenderMyStuff(FRHICommandListImmediate& RHICmdList)
{
         // ---- Create a partial object of frDGBuilder ----
    FRDGBuilder GraphBuilder(RHICmdList, RDG_EVENT_NAME("GraphBuilder_RenderMyStuff"));
    
    (......)
    
         // ---- Increase Pass ----
    
    GraphBuilder.AddPass(...);
    
    (......)
    
    GraphBuilder.AddPass(...);
    
    (......)
    
         // ---- Add resource extraction ----
    
    GraphBuilder.QueueTextureExtraction(...);
    
    (......)
    
         // ---- Execute frDGbuilder ----
    
    GraphBuilder.Execute();
}