Added missing env BRDF surface reduction. Now BRDF matches reference image.

ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightPipelineBRDF.cginc

 #endif
 }
 
-half3 LightweightBRDFIndirect(half3 diffColor, half3 specColor, UnityIndirect indirect, half grazingTerm, half fresnelTerm)
+half3 LightweightBRDFIndirect(half3 diffColor, half3 specColor, UnityIndirect indirect, float roughness, half grazingTerm, half fresnelTerm)
-    c += indirect.specular * lerp(specColor, grazingTerm, fresnelTerm);
+    float surfaceReduction = 1.0 / (roughness * roughness + 1.0);
+    c += surfaceReduction * indirect.specular * lerp(specColor, grazingTerm, fresnelTerm);
     return c;
 }
 

ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightStandardShader.shader

 
                 half3 viewDir = normalize(_WorldSpaceCameraPos - worldPos);
                 o.viewDir.xyz = viewDir;
-#ifndef _METALLICGLOSSMAP
-                o.viewDir.w = saturate(_Glossiness + MetallicSetup_Reflectivity()); // grazing term
-#endif
 
                 half3 normal = normalize(UnityObjectToWorldNormal(v.normal));
 
 #else
                 o.normal = normal;
 #endif
-
-                o.posWS.w = Pow4(1 - saturate(dot(normal, viewDir))); // fresnel term
 
 #if defined(_LIGHT_PROBES_ON) && !defined(LIGHTMAP_ON)
                 o.fogCoord.yzw += max(half3(0, 0, 0), ShadeSH9(half4(normal, 1)));
                 // grazingTerm = F90
                 half grazingTerm = saturate(smoothness + (1 - oneMinusReflectivity));
                 half fresnelTerm = Pow4(1.0 - saturate(dot(normal, i.viewDir.xyz)));
-                half3 color = LightweightBRDFIndirect(diffColor, specColor, indirectLight, grazingTerm, fresnelTerm);
+                half3 color = LightweightBRDFIndirect(diffColor, specColor, indirectLight, perceptualRoughness * perceptualRoughness, grazingTerm, fresnelTerm);
                 half3 lightDirection;
 
 #ifndef _MULTIPLE_LIGHTS

Tests/GraphicsTests/RenderPipeline/LightweightPipeline/Scenes/024_Shader_PBRvalidation/Adam/Materials/Crowd_LOD0_Mat_Limbs.mat

   m_PrefabInternal: {fileID: 0}
   m_Name: Crowd_LOD0_Mat_Limbs
   m_Shader: {fileID: 4800000, guid: 933532a4fcc9baf4fa0491de14d08ed7, type: 3}
-  m_ShaderKeywords: _GLOSSYREFLECTIONS_ON _METALLICSPECGLOSSMAP _METALLIC_SETUP _NORMALMAP
-    _SPECULARHIGHLIGHTS_ON
+  m_ShaderKeywords: _GLOSSYREFLECTIONS_ON _METALLICSPECGLOSSMAP _NORMALMAP _SPECULARHIGHLIGHTS_ON
+    _SPECULAR_SETUP
   m_LightmapFlags: 4
   m_EnableInstancingVariants: 0
   m_DoubleSidedGI: 0

Tests/GraphicsTests/RenderPipeline/LightweightPipeline/Scenes/024_Shader_PBRvalidation/Adam/Materials/Crowd_LOD0_Mat_Torso.mat

   m_PrefabInternal: {fileID: 0}
   m_Name: Crowd_LOD0_Mat_Torso
   m_Shader: {fileID: 4800000, guid: 933532a4fcc9baf4fa0491de14d08ed7, type: 3}
-  m_ShaderKeywords: _EMISSION _GLOSSYREFLECTIONS_ON _METALLICSPECGLOSSMAP _METALLIC_SETUP
-    _NORMALMAP _SPECULARHIGHLIGHTS_ON
+  m_ShaderKeywords: _EMISSION _GLOSSYREFLECTIONS_ON _METALLICSPECGLOSSMAP _NORMALMAP
+    _SPECULARHIGHLIGHTS_ON _SPECULAR_SETUP
   m_LightmapFlags: 1
   m_EnableInstancingVariants: 0
   m_DoubleSidedGI: 0