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03-UnrealEngine/卡通渲染相关资料/渲染功能/ShaderModel/BasePass C++.md

@@ -5,6 +5,62 @@ excerpt:
 tags: 
 rating: ⭐
 ---
+# RenderBasePass()
+传入RenderBasePass()的DepthStencil逻辑如下：
+```c++
+const FExclusiveDepthStencil::Type BasePassDepthStencilAccess =  
+    bAllowReadOnlyDepthBasePass  
+    ? FExclusiveDepthStencil::DepthRead_StencilWrite  
+    : FExclusiveDepthStencil::DepthWrite_StencilWrite;
+```
+
+
+FDeferredShadingSceneRenderer::RenderBasePass() =>
+FDeferredShadingSceneRenderer::RenderBasePassInternal() =>
+
+
+FBasePassMeshProcessor::TryAddMeshBatch =>
+
+## 大致流程
+1. 绑定GBuffer与Depth。
+```c++
+const FExclusiveDepthStencil ExclusiveDepthStencil(BasePassDepthStencilAccess);  
+  
+TStaticArray<FTextureRenderTargetBinding, MaxSimultaneousRenderTargets> BasePassTextures;  
+uint32 BasePassTextureCount = SceneTextures.GetGBufferRenderTargets(BasePassTextures);  
+Strata::AppendStrataMRTs(*this, BasePassTextureCount, BasePassTextures);  
+TArrayView<FTextureRenderTargetBinding> BasePassTexturesView = MakeArrayView(BasePassTextures.GetData(), BasePassTextureCount);  
+FRDGTextureRef BasePassDepthTexture = SceneTextures.Depth.Target;
+```
+2. GBuffer Clear
+```c++
+GraphBuilder.AddPass(RDG_EVENT_NAME("GBufferClear"), PassParameters, ERDGPassFlags::Raster,
+			[PassParameters, ColorLoadAction, SceneColorClearValue](FRHICommandList& RHICmdList)
+		{
+			// If no fast-clear action was used, we need to do an MRT shader clear.
+			if (ColorLoadAction == ERenderTargetLoadAction::ENoAction)
+			{
+				const FRenderTargetBindingSlots& RenderTargets = PassParameters->RenderTargets;
+				FLinearColor ClearColors[MaxSimultaneousRenderTargets];
+				FRHITexture* Textures[MaxSimultaneousRenderTargets];
+				int32 TextureIndex = 0;
+
+				RenderTargets.Enumerate([&](const FRenderTargetBinding& RenderTarget)
+				{
+					FRHITexture* TextureRHI = RenderTarget.GetTexture()->GetRHI();
+					ClearColors[TextureIndex] = TextureIndex == 0 ? SceneColorClearValue : TextureRHI->GetClearColor();
+					Textures[TextureIndex] = TextureRHI;
+					++TextureIndex;
+				});
+
+				// Clear color only; depth-stencil is fast cleared.
+				DrawClearQuadMRT(RHICmdList, true, TextureIndex, ClearColors, false, 0, false, 0);
+			}
+		});
+```
+3. 
+
+
 # SetDepthStencilStateForBasePass()
 ```c++
 void SetDepthStencilStateForBasePass(