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03-UnrealEngine/卡通渲染相关资料/渲染功能/阴影控制/ToonShadow.md

@@ -218,7 +218,174 @@ void FSceneRenderer::InitDynamicShadows(FRHICommandListImmediate& RHICmdList, FG
 		- **FProjectedShadowInfo::RenderTranslucencyDepths**
 
 ## RenderDepth
-FShadowParallelCommandListSet
+MeshDrawProcessor为***FShadowDepthPassMeshProcessor***。渲染的Shader为ShadowDepthPixelShader.usf
+```c++
+void FProjectedShadowInfo::RenderDepth(
+	FRDGBuilder& GraphBuilder,
+	const FSceneRenderer* SceneRenderer,
+	FRDGTextureRef ShadowDepthTexture,
+	bool bDoParallelDispatch,
+	bool bDoCrossGPUCopy)
+{
+#if WANTS_DRAW_MESH_EVENTS
+	FString EventName;
+
+	if (GetEmitDrawEvents())
+	{
+		GetShadowTypeNameForDrawEvent(EventName);
+		EventName += FString(TEXT(" ")) + FString::FromInt(ResolutionX) + TEXT("x") + FString::FromInt(ResolutionY);
+	}
+
+	RDG_EVENT_SCOPE(GraphBuilder, "%s", *EventName);
+#endif
+
+	CONDITIONAL_SCOPE_CYCLE_COUNTER(STAT_RenderWholeSceneShadowDepthsTime, bWholeSceneShadow);
+	CONDITIONAL_SCOPE_CYCLE_COUNTER(STAT_RenderPerObjectShadowDepthsTime, !bWholeSceneShadow);
+	QUICK_SCOPE_CYCLE_COUNTER(STAT_RenderShadowDepth);
+
+	FScene* Scene = SceneRenderer->Scene;
+	const ERHIFeatureLevel::Type FeatureLevel = ShadowDepthView->FeatureLevel;
+	BeginRenderView(GraphBuilder, Scene);
+
+	FShadowDepthPassParameters* PassParameters = GraphBuilder.AllocParameters<FShadowDepthPassParameters>();
+	PassParameters->View = ShadowDepthView->ViewUniformBuffer;
+	PassParameters->RenderTargets.DepthStencil = FDepthStencilBinding(
+		ShadowDepthTexture,
+		ERenderTargetLoadAction::ELoad,
+		ERenderTargetLoadAction::ENoAction,
+		FExclusiveDepthStencil::DepthWrite_StencilNop);
+
+	if (CacheMode == SDCM_MovablePrimitivesOnly || CacheMode == SDCM_CSMScrolling)
+	{
+		// Copy in depths of static primitives before we render movable primitives.
+		FMeshPassProcessorRenderState DrawRenderState;
+		SetStateForShadowDepth(bOnePassPointLightShadow, bDirectionalLight, DrawRenderState, MeshPassTargetType);
+		CopyCachedShadowMap(GraphBuilder, *ShadowDepthView, SceneRenderer, PassParameters->RenderTargets, DrawRenderState);
+	}
+
+	PassParameters->VirtualShadowMap = SceneRenderer->VirtualShadowMapArray.GetUniformBuffer();
+
+	switch (FSceneInterface::GetShadingPath(FeatureLevel))
+	{
+	case EShadingPath::Deferred:
+	{
+		auto* ShadowDepthPassParameters = GraphBuilder.AllocParameters<FShadowDepthPassUniformParameters>();
+		SetupShadowDepthPassUniformBuffer(this, GraphBuilder, *ShadowDepthView, *ShadowDepthPassParameters);//设置矩阵、Shader等相关ShadowDepthPassParameters参数
+		PassParameters->DeferredPassUniformBuffer = GraphBuilder.CreateUniformBuffer(ShadowDepthPassParameters);
+	}
+	break;
+	case EShadingPath::Mobile:
+	{
+		auto* ShadowDepthPassParameters = GraphBuilder.AllocParameters<FMobileShadowDepthPassUniformParameters>();
+		SetupShadowDepthPassUniformBuffer(this, GraphBuilder, *ShadowDepthView, *ShadowDepthPassParameters);//设置矩阵、Shader等相关ShadowDepthPassParameters参数
+		PassParameters->MobilePassUniformBuffer = GraphBuilder.CreateUniformBuffer(ShadowDepthPassParameters);
+	}
+	break;
+	default:
+		checkNoEntry();
+	}
+
+	ShadowDepthPass.BuildRenderingCommands(GraphBuilder, Scene->GPUScene, PassParameters->InstanceCullingDrawParams);
+
+#if WITH_MGPU
+	// Need to fetch GPU mask outside "AddPass", as it's not updated during pass execution
+	FRHIGPUMask GPUMask = GraphBuilder.RHICmdList.GetGPUMask();
+#endif
+
+	if (bDoParallelDispatch)
+	{
+		RDG_WAIT_FOR_TASKS_CONDITIONAL(GraphBuilder, IsShadowDepthPassWaitForTasksEnabled());
+
+		GraphBuilder.AddPass(
+			RDG_EVENT_NAME("ShadowDepthPassParallel"),
+			PassParameters,
+			ERDGPassFlags::Raster | ERDGPassFlags::SkipRenderPass,
+			[this, PassParameters
+#if WITH_MGPU
+			, ShadowDepthTexture, GPUMask, bDoCrossGPUCopy
+#endif
+			](const FRDGPass* InPass, FRHICommandListImmediate& RHICmdList)
+		{
+			FShadowParallelCommandListSet ParallelCommandListSet(InPass, RHICmdList, *ShadowDepthView, *this, FParallelCommandListBindings(PassParameters));
+			ShadowDepthPass.DispatchDraw(&ParallelCommandListSet, RHICmdList, &PassParameters->InstanceCullingDrawParams);
+
+#if WITH_MGPU
+			if (bDoCrossGPUCopy)
+			{
+				CopyCachedShadowMapCrossGPU(RHICmdList, ShadowDepthTexture->GetRHI(), GPUMask);
+			}
+#endif
+		});
+	}
+	else
+	{
+		GraphBuilder.AddPass(
+			RDG_EVENT_NAME("ShadowDepthPass"),
+			PassParameters,
+			ERDGPassFlags::Raster,
+			[this, PassParameters
+#if WITH_MGPU
+			, ShadowDepthTexture, GPUMask, bDoCrossGPUCopy
+#endif
+			](FRHICommandList& RHICmdList)
+		{
+			SetStateForView(RHICmdList);
+			ShadowDepthPass.DispatchDraw(nullptr, RHICmdList, &PassParameters->InstanceCullingDrawParams);
+
+#if WITH_MGPU
+			if (bDoCrossGPUCopy)
+			{
+				CopyCachedShadowMapCrossGPU(RHICmdList, ShadowDepthTexture->GetRHI(), GPUMask);
+			}
+#endif
+		});
+	}
+}
+```
+
+```c++
+void SetupShadowDepthPassUniformBuffer(
+	const FProjectedShadowInfo* ShadowInfo,
+	FRDGBuilder& GraphBuilder,
+	const FViewInfo& View,
+	FShadowDepthPassUniformParameters& ShadowDepthPassParameters)
+{
+	static const auto CSMCachingCVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.Shadow.CSMCaching"));
+	const bool bCSMCachingEnabled = CSMCachingCVar && CSMCachingCVar->GetValueOnAnyThread() != 0;
+
+	SetupSceneTextureUniformParameters(GraphBuilder, View.GetSceneTexturesChecked(), View.FeatureLevel, ESceneTextureSetupMode::None, ShadowDepthPassParameters.SceneTextures);//设置对应的RT与Texture
+
+	ShadowDepthPassParameters.ProjectionMatrix = FTranslationMatrix44f(FVector3f(ShadowInfo->PreShadowTranslation - View.ViewMatrices.GetPreViewTranslation())) * ShadowInfo->TranslatedWorldToClipOuterMatrix;		// LWC_TDOO: Precision loss?
+	ShadowDepthPassParameters.ViewMatrix = FMatrix44f(ShadowInfo->TranslatedWorldToView);	// LWC_TODO: Precision loss
+
+	// Disable the SlopeDepthBias because we couldn't reconstruct the depth offset if it is not 0.0f when scrolling the cached shadow map.
+	ShadowDepthPassParameters.ShadowParams = FVector4f(ShadowInfo->GetShaderDepthBias(), bCSMCachingEnabled ? 0.0f : ShadowInfo->GetShaderSlopeDepthBias(), ShadowInfo->GetShaderMaxSlopeDepthBias(), ShadowInfo->bOnePassPointLightShadow ? 1 : ShadowInfo->InvMaxSubjectDepth);
+	ShadowDepthPassParameters.bClampToNearPlane = ShadowInfo->ShouldClampToNearPlane() ? 1.0f : 0.0f;
+
+	if (ShadowInfo->bOnePassPointLightShadow)
+	{
+		check(ShadowInfo->BorderSize == 0);
+
+		// offset from translated world space to (pre translated) shadow space 
+		const FMatrix Translation = FTranslationMatrix(ShadowInfo->PreShadowTranslation - View.ViewMatrices.GetPreViewTranslation());
+
+		for (int32 FaceIndex = 0; FaceIndex < 6; FaceIndex++)
+		{
+			ShadowDepthPassParameters.ShadowViewProjectionMatrices[FaceIndex] = FMatrix44f(Translation * ShadowInfo->OnePassShadowViewProjectionMatrices[FaceIndex]);		// LWC_TODO: Precision loss?
+			ShadowDepthPassParameters.ShadowViewMatrices[FaceIndex] = FMatrix44f(Translation * ShadowInfo->OnePassShadowViewMatrices[FaceIndex]);
+		}
+	}
+
+	ShadowDepthPassParameters.bRenderToVirtualShadowMap = false;
+	ShadowDepthPassParameters.VirtualSmPageTable = GraphBuilder.CreateSRV(GSystemTextures.GetDefaultStructuredBuffer(GraphBuilder, sizeof(uint32)));
+	ShadowDepthPassParameters.PackedNaniteViews = GraphBuilder.CreateSRV(GSystemTextures.GetDefaultStructuredBuffer(GraphBuilder, sizeof(Nanite::FPackedView)));
+	ShadowDepthPassParameters.PageRectBounds = GraphBuilder.CreateSRV(GSystemTextures.GetDefaultStructuredBuffer(GraphBuilder, sizeof(FIntVector4)));
+
+	FRDGTextureRef DepthBufferArray = GraphBuilder.CreateTexture( FRDGTextureDesc::Create2DArray( FIntPoint(4,4), PF_R32_UINT, FClearValueBinding::None, TexCreate_ShaderResource | TexCreate_UAV, 1 ), TEXT("Dummy-OutDepthBuffer") );
+
+	ShadowDepthPassParameters.OutDepthBufferArray = GraphBuilder.CreateUAV( DepthBufferArray );
+}
+```
 
 # Lights
 ### Shader