[7.x.x Backport] Fix an issue in reading the gbuffer for ray traced subsurface scattering (case 1248358)

com.unity.render-pipelines.high-definition/CHANGELOG.md

@@ -90,6 +90,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed issue that prevented cubemap thumbnails from rendering (only on D3D11 and Metal).
 - Fixed Microshadow not working correctly in deferred with LightLayers
 - Tentative fix for missing include in depth of field shaders.
+- Fix an issue in reading the gbuffer for ray traced subsurface scattering (case 1248358).
 
 ### Changed
 - Rejecting history for ray traced reflections based on a threshold evaluated on the neighborhood of the sampled history.

com.unity.render-pipelines.high-definition/Runtime/Material/SubsurfaceScattering/SubsurfaceScatteringManager.cs

@@ -350,10 +350,6 @@ void RenderSubsurfaceScattering(HDCamera hdCamera, CommandBuffer cmd, RTHandle c
                         // Bind the textures for ray generation
                         cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._DepthTexture, sharedRTManager.GetDepthStencilBuffer());
                         cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._NormalBufferTexture, sharedRTManager.GetNormalBuffer());
-                        cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._GBufferTexture[0], m_GbufferManager.GetBuffer(0));
-                        cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._GBufferTexture[1], m_GbufferManager.GetBuffer(1));
-                        cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._GBufferTexture[2], m_GbufferManager.GetBuffer(2));
-                        cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._GBufferTexture[3], m_GbufferManager.GetBuffer(3));
                         cmd.SetRayTracingTextureParam(subSurfaceShader, HDShaderIDs._SSSBufferTexture, m_SSSColor);
                         cmd.SetGlobalTexture(HDShaderIDs._StencilTexture, sharedRTManager.GetDepthStencilBuffer(), RenderTextureSubElement.Stencil);
 

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/Raytracing/Shaders/RayTracingSubSurface.raytrace

@@ -66,13 +66,9 @@ void RayGenSubSurface()
     PositionInputs posInput = GetPositionInput(currentPixelCoord, 1.0/LaunchDim.xy, depthValue, UNITY_MATRIX_I_VP, GetWorldToViewMatrix(), 0);
     posInput.positionWS = GetAbsolutePositionWS(posInput.positionWS);
 
-    // Read the bsdf data and builtin data from the gbuffer
-    BSDFData bsdfData;
-    ZERO_INITIALIZE(BSDFData, bsdfData);
-    BuiltinData builtinData;
-    ZERO_INITIALIZE(BuiltinData, builtinData);
-    uint featureFlags = MATERIALFEATUREFLAGS_LIT_SUBSURFACE_SCATTERING;
-    DecodeFromGBuffer(currentPixelCoord, featureFlags, bsdfData, builtinData);
+    // Read the normal data
+    NormalData normalData;
+    DecodeFromNormalBuffer(currentPixelCoord, normalData);
 
     // Read the SSS Data
     SSSData sssData;
@@ -88,7 +84,7 @@ void RayGenSubSurface()
 
     // Do our walk
     ScatteringResult scatteringResult;
-    ScatteringWalk(bsdfData.normalWS, bsdfData.diffuseColor, scatteringDistance, currentPixelCoord, globalSampleIndex, posInput.positionWS, scatteringResult);
+    ScatteringWalk(normalData.normalWS, sssData.diffuseColor, scatteringDistance, currentPixelCoord, globalSampleIndex, posInput.positionWS, scatteringResult);
 
     // Normalize the throughput
     scatteringResult.outputThroughput /= (float)_RaytracingNumSamples;