UE4的自定义ScreenPass和MRT输出

// Fill out your copyright notice in the Description page of Project Settings. #include "MyShaderBPFunctionLibrary.h" #include "DrawShader.h" #include "Engine/TextureRenderTarget2D.h" #include "Engine/World.h" #include "GlobalShader.h" #include "CommonRenderResources.h" #include "ScreenRendering.h" static void DrawTestShaderToRenderTexture_RenderThread( FRHICommandListImmediate& RHICmdList, FTexture* InTextureResource, FTextureRenderTargetResource* OutGrayRTReource, FTextureRenderTargetResource* OutScaleRTReource, ERHIFeatureLevel::Type FeatureLevel, const FLinearColor& Color, float ColorScale) { check(IsInRenderingThread()); FRHITexture2D* OutGrayRTT = OutGrayRTReource->GetRenderTargetTexture(); FRHITexture2D* OutScaleRTT = OutScaleRTReource->GetRenderTargetTexture(); if (nullptr == OutGrayRTT || nullptr == OutScaleRTT) return; if (OutGrayRTT->GetSizeX() != OutScaleRTT->GetSizeX() || OutGrayRTT->GetSizeY() != OutScaleRTT->GetSizeY()) return; FRHITexture* RTS[] = { OutGrayRTT, OutScaleRTT }; IRendererModule* RendererModule = &FModuleManager::GetModuleChecked<IRendererModule>("Renderer"); RHICmdList.Transition(FRHITransitionInfo(OutGrayRTT, ERHIAccess::SRVMask, ERHIAccess::RTV)); RHICmdList.Transition(FRHITransitionInfo(OutScaleRTT, ERHIAccess::SRVMask, ERHIAccess::RTV)); FRHIRenderPassInfo RPInfo(2, RTS, ERenderTargetActions::DontLoad_Store); RHICmdList.BeginRenderPass(RPInfo, TEXT("Render Test Shader To Texture")); { // Get Shaders FGlobalShaderMap* GlobalShaderMap = GetGlobalShaderMap(FeatureLevel); TShaderMapRef<FScreenVS> VertexShader(GlobalShaderMap); TShaderMapRef<FDrawPS> PixelShader(GlobalShaderMap); // Setup Pipeline state FGraphicsPipelineStateInitializer GraphicsPSOInit; RHICmdList.ApplyCachedRenderTargets(GraphicsPSOInit); GraphicsPSOInit.DepthStencilState = TStaticDepthStencilState<false, CF_Always>::GetRHI(); GraphicsPSOInit.BlendState = TStaticBlendState<>::GetRHI(); GraphicsPSOInit.RasterizerState = TStaticRasterizerState<>::GetRHI(); GraphicsPSOInit.PrimitiveType = PT_TriangleList; GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GFilterVertexDeclaration.VertexDeclarationRHI; GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader(); GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader(); SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit); // Upate viewport FIntPoint ViewportSize(OutGrayRTT->GetSizeX(), OutGrayRTT->GetSizeY()); RHICmdList.SetViewport(0, 0, 0.0f, ViewportSize.X, ViewportSize.Y, 1.0f); // update shader uniform parameters PixelShader->SetParam(RHICmdList, InTextureResource, Color, ColorScale); RendererModule->DrawRectangle(RHICmdList, 0, 0, ViewportSize.X, ViewportSize.Y, 0, 0, 1, 1, ViewportSize, FIntPoint(1, 1), VertexShader); } RHICmdList.EndRenderPass(); RHICmdList.Transition(FRHITransitionInfo(OutGrayRTT, ERHIAccess::RTV, ERHIAccess::SRVMask)); RHICmdList.Transition(FRHITransitionInfo(OutScaleRTT, ERHIAccess::RTV, ERHIAccess::SRVMask)); } void UMyShaderBPFunctionLibrary::DrawTestShaderToRenderTexture( const UObject* WorldContextObject, const UTexture2D* InTexture, class UTextureRenderTarget2D* OutputRenderTargetA, class UTextureRenderTarget2D* OutputRenderTargetB, const FLinearColor& Color, float ColorScale) { UWorld* World = WorldContextObject->GetWorld(); ERHIFeatureLevel::Type FeatureLevel = World->Scene->GetFeatureLevel(); if (FeatureLevel < ERHIFeatureLevel::SM5) { UE_LOG(LogTemp, Warning, TEXT("FeatureLevel < ERHIFeatureLevel::SM5")); return; } if (nullptr == InTexture) { UE_LOG(LogTemp, Warning, TEXT("InTexture Is NULL")); return; } FTextureRenderTargetResource* TextureRenderTargetSourceA = OutputRenderTargetA->GameThread_GetRenderTargetResource(); FTextureRenderTargetResource* TextureRenderTargetSourceB = OutputRenderTargetB->GameThread_GetRenderTargetResource(); FTexture* TextureSource = InTexture->Resource; ENQUEUE_RENDER_COMMAND(TestShaderCommand)( [TextureSource, TextureRenderTargetSourceA, TextureRenderTargetSourceB, FeatureLevel, Color, ColorScale](FRHICommandListImmediate& RHICmdList) { DrawTestShaderToRenderTexture_RenderThread(RHICmdList, TextureSource, TextureRenderTargetSourceA, TextureRenderTargetSourceB, FeatureLevel, Color, ColorScale); } ); }