Support SeparateTranslucencyScreenPercentage on mobile platforms.

Author: YOung

Engine/Shaders/Private/DownsampleDepthPixelShader.usf

@@ -13,6 +13,7 @@
 #define DOWNSAMPLE_DEPTH_FILTER_CBMINMAX	2
 
 Texture2D<float> DepthTexture;
+SamplerState DepthTexturePointClampedSampler;
 float4 SourceTexelOffsets01;
 float4 SourceTexelOffsets23;
 float2 SourceMaxUV;
@@ -21,7 +22,7 @@ uint DownsampleDepthFilter;
 
 float GetDeviceZ(float2 UV)
 {
-	return DepthTexture.Sample(GlobalPointClampedSampler, min(UV, SourceMaxUV));
+	return DepthTexture.Sample(DepthTexturePointClampedSampler, min(UV, SourceMaxUV));
 }
 
 void Main(

Engine/Shaders/Private/SeparateTranslucency.ush

@@ -9,6 +9,9 @@
 Texture2D<float> LowResDepthTexture;
 Texture2D<float> FullResDepthTexture;
 
+SamplerState PointClampedSampler;
+SamplerState BilinearClampedSampler;
+
 void UpdateNearestSample(float Z, float2 UV, float FullResZ, inout float MinDist, inout float2 NearestUV)
 {
     float DepthDelta = abs(Z - FullResZ);
@@ -23,7 +26,7 @@ void UpdateNearestSample(float Z, float2 UV, float FullResZ, inout float MinDist
 
 float4 BilinearUpsampling(float2 UV, Texture2D LowResTex)
 {
-	return Texture2DSample(LowResTex, GlobalBilinearClampedSampler, UV);
+	return Texture2DSample(LowResTex, BilinearClampedSampler, UV);
 }
 
 float4 NearestDepthNeighborUpsampling(float2 Position, float2 UV, Texture2D LowResTex, float2 LowResTexelSize)
@@ -35,7 +38,7 @@ float4 NearestDepthNeighborUpsampling(float2 Position, float2 UV, Texture2D LowR
 	float MaxOperationDepth = 2000000.0f;
 
 	// Note: this upsample is specialized for half res to full res
-    float4 LowResDepthBuffer = LowResDepthTexture.GatherRed(GlobalBilinearClampedSampler, UV);
+    float4 LowResDepthBuffer = LowResDepthTexture.GatherRed(BilinearClampedSampler, UV);
     float4 LowResDepth = min(float4(ConvertFromDeviceZ(LowResDepthBuffer.x), ConvertFromDeviceZ(LowResDepthBuffer.y), ConvertFromDeviceZ(LowResDepthBuffer.z), ConvertFromDeviceZ(LowResDepthBuffer.w)), MaxOperationDepth.xxxx);
 	float FullResDepth = min(ConvertFromDeviceZ(FullResDepthTexture[uint2(Position.xy)].x), MaxOperationDepth);
 
@@ -66,18 +69,18 @@ float4 NearestDepthNeighborUpsampling(float2 Position, float2 UV, Texture2D LowR
 		&& abs(LowResDepth.x - FullResDepth) * InvFullResDepth < RelativeDepthThreshold
 		&& abs(LowResDepth.y - FullResDepth) * InvFullResDepth < RelativeDepthThreshold)
     {
-        Output = Texture2DSampleLevel(LowResTex, GlobalBilinearClampedSampler, UV, 0);
+        Output = Texture2DSampleLevel(LowResTex, BilinearClampedSampler, UV, 0);
     }
     else
     {
-        Output = Texture2DSampleLevel(LowResTex, GlobalPointClampedSampler, NearestUV, 0);
+        Output = Texture2DSampleLevel(LowResTex, PointClampedSampler, NearestUV, 0);
     }
 
 	return Output;
 
 #else
 
-	return Texture2DSample(LowResTex, GlobalBilinearClampedSampler, UV);
+	return Texture2DSample(LowResTex, BilinearClampedSampler, UV);
 
 #endif
 }

Engine/Source/Runtime/Engine/Private/Materials/MaterialInterface.cpp

@@ -211,7 +211,7 @@ FMaterialRelevance UMaterialInterface::GetRelevance_Internal(const UMaterial* Ma
 		{
 			// Check whether the material can be drawn in the separate translucency pass as per FMaterialResource::IsTranslucencyAfterDOFEnabled and IsMobileSeparateTranslucencyEnabled
 			bool bSupportsSeparateTranslucency = Material->MaterialDomain != MD_UI && Material->MaterialDomain != MD_DeferredDecal;
-			bool bMaterialSeparateTranslucency = bSupportsSeparateTranslucency && (bIsMobile ? Material->bEnableMobileSeparateTranslucency : Material->bEnableSeparateTranslucency);
+			bool bMaterialSeparateTranslucency = bSupportsSeparateTranslucency && Material->bEnableSeparateTranslucency;
 
 			// If dual blending is supported, and we are rendering separate translucency, then we also need to render a second pass to the modulation buffer.
 			// The modulation buffer can also be used for regular modulation shaders after DoF.

Engine/Source/Runtime/Renderer/Private/DepthRendering.cpp

@@ -28,6 +28,7 @@
 #include "ClearQuad.h"
 #include "GPUSkinCache.h"
 #include "MeshPassProcessor.inl"
+#include "MobileShadingRenderer.h"
 
 static TAutoConsoleVariable<int32> CVarParallelPrePass(
 	TEXT("r.ParallelPrePass"),

Engine/Source/Runtime/Renderer/Private/EditorPrimitivesRendering.cpp

@@ -134,7 +134,7 @@ void FEditorPrimitivesBasePassMeshProcessor::ProcessMobileShadingPath(const FMes
 
 	if (bTranslucentBasePass)
 	{
-		MobileBasePass::SetTranslucentRenderState(DrawRenderState, Material);
+		MobileBasePass::SetTranslucentRenderState(DrawRenderState, Material, ETranslucencyPass::TPT_AllTranslucency);
 	}
 
 	const FMeshDrawingPolicyOverrideSettings OverrideSettings = ComputeMeshOverrideSettings(MeshBatch);

Engine/Source/Runtime/Renderer/Private/MobileBasePass.cpp

@@ -374,10 +374,14 @@ void MobileBasePass::SetOpaqueRenderState(FMeshPassProcessorRenderState& DrawRen
 	}
 }
 
-void MobileBasePass::SetTranslucentRenderState(FMeshPassProcessorRenderState& DrawRenderState, const FMaterial& Material)
+void MobileBasePass::SetTranslucentRenderState(FMeshPassProcessorRenderState& DrawRenderState, const FMaterial& Material, ETranslucencyPass::Type InTranslucencyPassType)
 {
 	const bool bIsUsingMobilePixelProjectedReflection = Material.IsUsingPlanarForwardReflections() && IsUsingMobilePixelProjectedReflection(GetFeatureLevelShaderPlatform(Material.GetFeatureLevel()));
 
+	static const auto CVar = IConsoleManager::Get().FindTConsoleVariableDataFloat(TEXT("r.SeparateTranslucencyScreenPercentage"));
+	const float DownsampleScale = CVar ? FMath::Clamp(CVar->GetValueOnRenderThread() / 100.0f, 0.0f, 1.0f) : 1.0f;
+	const bool bSeparateTranslucencyActive = IsMobileSeparateTranslucencyColorTextureEnabled(InTranslucencyPassType, DownsampleScale);
+
 	if (Material.GetShadingModels().HasShadingModel(MSM_ThinTranslucent))
 	{
 		// the mobile thin translucent fallback uses a similar mode as BLEND_Translucent, but multiplies color by 1 insead of SrcAlpha.
@@ -394,20 +398,28 @@ void MobileBasePass::SetTranslucentRenderState(FMeshPassProcessorRenderState& Dr
 			}
 			else
 			{
-				DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_SourceAlpha, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
+				bSeparateTranslucencyActive
+					? DrawRenderState.SetBlendState(TStaticBlendState<CW_RGBA, BO_Add, BF_SourceAlpha, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI())
+					: DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_SourceAlpha, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
 			}
 			break;
 		case BLEND_Additive:
 			// Add to the existing scene color
-			DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_One, BF_One, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
+			bSeparateTranslucencyActive
+				? DrawRenderState.SetBlendState(TStaticBlendState<CW_RGBA, BO_Add, BF_One, BF_One, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI())
+				: DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_One, BF_One, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
 			break;
 		case BLEND_Modulate:
 			// Modulate with the existing scene color
-			DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_DestColor, BF_Zero>::GetRHI());
+			bSeparateTranslucencyActive
+				? DrawRenderState.SetBlendState(TStaticBlendState<CW_RGBA, BO_Add, BF_DestColor, BF_Zero>::GetRHI())
+				: DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_DestColor, BF_Zero>::GetRHI());
 			break;
 		case BLEND_AlphaComposite:
 			// Blend with existing scene color. New color is already pre-multiplied by alpha.
-			DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_One, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
+			bSeparateTranslucencyActive
+				? DrawRenderState.SetBlendState(TStaticBlendState<CW_RGBA, BO_Add, BF_One, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI())
+				: DrawRenderState.SetBlendState(TStaticBlendState<CW_RGB, BO_Add, BF_One, BF_InverseSourceAlpha, BO_Add, BF_Zero, BF_InverseSourceAlpha>::GetRHI());
 			break;
 		case BLEND_AlphaHoldout:
 			// Blend by holding out the matte shape of the source alpha
@@ -657,8 +669,8 @@ void FMobileBasePassMeshProcessor::AddMeshBatch(const FMeshBatch& RESTRICT MeshB
 		// Skipping TPT_TranslucencyAfterDOFModulate. That pass is only needed for Dual Blending, which is not supported on Mobile.
 		bool bShouldDraw = (bIsTranslucent || bUsesWaterMaterial || bIsUsingMobilePixelProjectedReflection) &&
 		(TranslucencyPassType == ETranslucencyPass::TPT_AllTranslucency
-		|| (TranslucencyPassType == ETranslucencyPass::TPT_StandardTranslucency && !Material.IsMobileSeparateTranslucencyEnabled())
-		|| (TranslucencyPassType == ETranslucencyPass::TPT_TranslucencyAfterDOF && Material.IsMobileSeparateTranslucencyEnabled()));
+		|| TranslucencyPassType == ETranslucencyPass::TPT_StandardTranslucency
+		|| TranslucencyPassType == ETranslucencyPass::TPT_TranslucencyAfterDOF);
 
 		if (bShouldDraw)
 		{
@@ -735,7 +747,7 @@ void FMobileBasePassMeshProcessor::Process(
 	{
 		if (bTranslucentBasePass)
 		{
-			MobileBasePass::SetTranslucentRenderState(DrawRenderState, MaterialResource);
+			MobileBasePass::SetTranslucentRenderState(DrawRenderState, MaterialResource, TranslucencyPassType);
 		}
 		else if (bMaskedInEarlyPass)
 		{

Engine/Source/Runtime/Renderer/Private/MobileBasePassRendering.cpp

@@ -17,6 +17,7 @@
 
 #include "FramePro/FrameProProfiler.h"
 #include "PostProcess/PostProcessPixelProjectedReflectionMobile.h"
+#include "MobileShadingRenderer.h"
 
 // Changing this causes a full shader recompile
 static TAutoConsoleVariable<int32> CVarMobileDisableVertexFog(

Engine/Source/Runtime/Renderer/Private/MobileBasePassRendering.h

@@ -353,7 +353,7 @@ namespace MobileBasePass
 	bool StaticCanReceiveCSM(const FLightSceneInfo* LightSceneInfo, const FPrimitiveSceneProxy* PrimitiveSceneProxy);
 
 	void SetOpaqueRenderState(FMeshPassProcessorRenderState& DrawRenderState, const FPrimitiveSceneProxy* PrimitiveSceneProxy, const FMaterial& Material, bool bEnableReceiveDecalOutput, bool bUsesDeferredShading);
-	void SetTranslucentRenderState(FMeshPassProcessorRenderState& DrawRenderState, const FMaterial& Material);
+	void SetTranslucentRenderState(FMeshPassProcessorRenderState& DrawRenderState, const FMaterial& Material, ETranslucencyPass::Type InTranslucencyPassType);
 
 	bool StationarySkyLightHasBeenApplied(const FScene* Scene, ELightMapPolicyType LightMapPolicyType);
 };

Engine/Source/Runtime/Renderer/Private/MobileDecalRendering.cpp

@@ -14,6 +14,7 @@
 #include "SceneRendering.h"
 #include "ScenePrivate.h"
 #include "DecalRenderingShared.h"
+#include "MobileShadingRenderer.h"
 
 extern FRHIRasterizerState* GetDecalRasterizerState(EDecalRasterizerState DecalRasterizerState);
 extern void RenderMeshDecalsMobile(FRHICommandList& RHICmdList, const FViewInfo& View);

Engine/Source/Runtime/Renderer/Private/MobileSceneCaptureRendering.cpp

@@ -28,6 +28,7 @@ MobileSceneCaptureRendering.cpp - Mobile specific scene capture code.
 #include "PipelineStateCache.h"
 #include "CommonRenderResources.h"
 #include "GenerateMips.h"
+#include "MobileShadingRenderer.h"
 
 /**
 * Shader set for the copy of scene color to capture target, alpha channel will contain opacity information. (Determined from depth buffer content)