Fixed decal normal for double sided materials (case 1312065)

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

@@ -48,6 +48,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed performance issue with ShaderGraph and Alpha Test
 - Fixed error when increasing the maximum planar reflection limit (case 1306530).
 - Fixed alpha output in debug view and AOVs when using shadow matte (case 1311830).
+- Fixed decal normal for double sided materials (case 1312065).
 
 ### Changed
 - Changed Window/Render Pipeline/HD Render Pipeline Wizard to Window/Rendering/HDRP Wizard

com.unity.render-pipelines.high-definition/Documentation~/Upgrading-from-2021.1-to-2021.2.md

@@ -5,3 +5,8 @@
 From 2021.2, if material ambient occlusion needs to be applied to probe volume GI and the material is deferred, the material needs to define `HAS_PAYLOAD_WITH_UNINIT_GI` constant and a function `float GetUninitializedGIPayload(SurfaceData surfaceData)` that returns the AO factor that is desired to be applied. No action is needed for forward only materials or if no material AO needs to be applied to probe volume GI.
 
 HDRP 2021.2 includes the "ForwardEmissiveForDeferred" shader pass and the associated SHADERPASS_FORWARD_EMISSIVE_FOR_DEFERRED define for Materials that have a GBuffer pass. You can see the new pass in Lit.shader. When you use the Deferred Lit shader mode, Unity uses "ForwardEmissiveForDeferred" to render the emissive contribution of a Material in a separate forward pass. Otherwise, Unity ignores "ForwardEmissiveForDeferred".
+
+From 2021.2, a decal function in shader code has been added. To handle normal flipping for double sided materials, calls to `GetDecalSurfaceData()` should be updated from this function:
+`DecalSurfaceData GetDecalSurfaceData(PositionInputs posInput, float3 vtxNormal, inout float alpha)`
+to:
+`DecalSurfaceData GetDecalSurfaceData(PositionInputs posInput, FragInputs input, inout float alpha)`

com.unity.render-pipelines.high-definition/Editor/Material/Eye/ShaderGraph/ShaderPass.template.hlsl

@@ -75,7 +75,7 @@ void BuildSurfaceData(FragInputs fragInputs, inout SurfaceDescription surfaceDes
             $SurfaceDescription.Alpha: alpha = surfaceDescription.Alpha;
 
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, fragInputs.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Editor/Material/Fabric/ShaderGraph/ShaderPass.template.hlsl

@@ -85,7 +85,7 @@ void BuildSurfaceData(FragInputs fragInputs, inout SurfaceDescription surfaceDes
             $SurfaceDescription.Alpha: alpha = surfaceDescription.Alpha;
 
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, fragInputs.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Editor/Material/Hair/ShaderGraph/ShaderPass.template.hlsl

@@ -103,7 +103,7 @@ void BuildSurfaceData(FragInputs fragInputs, inout SurfaceDescription surfaceDes
             $SurfaceDescription.Alpha: alpha = surfaceDescription.Alpha;
 
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, fragInputs.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Editor/Material/Lit/ShaderGraph/ShaderPass.template.hlsl

@@ -103,7 +103,7 @@ void BuildSurfaceData(FragInputs fragInputs, inout SurfaceDescription surfaceDes
             $SurfaceDescription.Alpha: alpha = surfaceDescription.Alpha;
 
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, fragInputs.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Editor/Material/StackLit/ShaderGraph/ShaderPass.template.hlsl

@@ -147,7 +147,7 @@ void BuildSurfaceData(FragInputs fragInputs, inout SurfaceDescription surfaceDes
             $SurfaceDescription.Alpha: alpha = surfaceDescription.Alpha;
 
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, fragInputs, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, fragInputs.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Runtime/Material/AxF/AxFData.hlsl

@@ -717,7 +717,7 @@ void GetSurfaceAndBuiltinData(FragInputs input, float3 V, inout PositionInputs p
         if (_EnableDecals)
         {
             // Both uses and modifies 'surfaceData.normalWS'.
-            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input.tangentToWorld[2], alpha);
+            DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input, alpha);
             ApplyDecalToSurfaceData(decalSurfaceData, input.tangentToWorld[2], surfaceData);
         }
     #endif

com.unity.render-pipelines.high-definition/Runtime/Material/Decal/DecalUtilities.hlsl

@@ -261,3 +261,18 @@ DecalSurfaceData GetDecalSurfaceData(PositionInputs posInput, float3 vtxNormal,
 
     return decalSurfaceData;
 }
+
+DecalSurfaceData GetDecalSurfaceData(PositionInputs posInput, FragInputs input, inout float alpha)
+{
+    float3 vtxNormal = input.tangentToWorld[2];
+    DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, vtxNormal, alpha);
+
+#ifdef _DOUBLESIDED_ON
+    // 'doubleSidedConstants' is float3(-1, -1, -1) in flip mode and float3(1, 1, -1) in mirror mode.
+    // It's float3(1, 1, 1) in the none mode.
+    float3 flipSign = input.isFrontFace ? float3(1.0, 1.0, 1.0) : _DoubleSidedConstants;
+    decalSurfaceData.normalWS *= flipSign;
+#endif // _DOUBLESIDED_ON
+
+    return decalSurfaceData;
+}

com.unity.render-pipelines.high-definition/Runtime/Material/LayeredLit/LayeredLitData.hlsl

@@ -772,7 +772,7 @@ void GetSurfaceAndBuiltinData(FragInputs input, float3 V, inout PositionInputs p
     if (_EnableDecals)
     {
         // Both uses and modifies 'surfaceData.normalWS'.
-        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input.tangentToWorld[2], alpha);
+        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input, alpha);
         ApplyDecalToSurfaceData(decalSurfaceData, input.tangentToWorld[2], surfaceData);
     }
 #endif

com.unity.render-pipelines.high-definition/Runtime/Material/Lit/Lit.shader

@@ -241,6 +241,7 @@ Shader "HDRP/Lit"
     HLSLINCLUDE
 
     #pragma target 4.5
+    //#pragma enable_d3d11_debug_symbols
 
     //-------------------------------------------------------------------------------------
     // Variant

com.unity.render-pipelines.high-definition/Runtime/Material/Lit/LitData.hlsl

@@ -247,7 +247,7 @@ void GetSurfaceAndBuiltinData(FragInputs input, float3 V, inout PositionInputs p
     if (_EnableDecals)
     {
         // Both uses and modifies 'surfaceData.normalWS'.
-        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input.tangentToWorld[2], alpha);
+        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input, alpha);
         ApplyDecalToSurfaceData(decalSurfaceData, input.tangentToWorld[2], surfaceData);
     }
 #endif

com.unity.render-pipelines.high-definition/Runtime/Material/TerrainLit/TerrainLitData.hlsl

@@ -221,7 +221,7 @@ void GetSurfaceAndBuiltinData(inout FragInputs input, float3 V, inout PositionIn
     {
         float alpha = 1.0; // unused
                            // Both uses and modifies 'surfaceData.normalWS'.
-        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input.tangentToWorld[2], alpha);
+        DecalSurfaceData decalSurfaceData = GetDecalSurfaceData(posInput, input, alpha);
         ApplyDecalToSurfaceData(decalSurfaceData, input.tangentToWorld[2], surfaceData);
     }
 #endif