Fix issue with SC_PrimitiveID not handlded correctly for overdraw (fail to compil with XR)

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

@@ -183,6 +183,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Meshes assigned with a decal material are not visible anymore in ray-tracing or path-tracing.
 - Removed BLEND shader keywords.
 - Remove a rendergraph debug option to clear resources on release from UI.
+- added SV_PrimitiveID in the VaryingMesh structure for fulldebugscreenpass as well as primitiveID in FragInputs
 
 ## [10.0.0] - 2019-06-10
 

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/HDStructFields.cs

@@ -54,6 +54,8 @@ public struct VaryingsMeshToPS
                 subscriptOptions : StructFieldOptions.Optional);
             public static FieldDescriptor instanceID = new FieldDescriptor(VaryingsMeshToPS.name, "instanceID", "", ShaderValueType.Uint,
                 "CUSTOM_INSTANCE_ID", "UNITY_ANY_INSTANCING_ENABLED");
+            public static FieldDescriptor primitiveID = new FieldDescriptor(VaryingsMeshToPS.name, "primitiveID", "VARYINGS_NEED_PRIMITIVEID", ShaderValueType.Uint,
+                "SV_PrimitiveID", "defined(PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER) && defined(SHADER_STAGE_FRAGMENT) && (defined(VARYINGS_NEED_PRIMITIVEID) || (SHADERPASS == SHADERPASS_FULLSCREEN_DEBUG))", StructFieldOptions.Generated & StructFieldOptions.Optional);
             public static FieldDescriptor cullFace = new FieldDescriptor(VaryingsMeshToPS.name, "cullFace", "VARYINGS_NEED_CULLFACE", "FRONT_FACE_TYPE",
                 "FRONT_FACE_SEMANTIC", "defined(SHADER_STAGE_FRAGMENT) && defined(VARYINGS_NEED_CULLFACE)", StructFieldOptions.Generated & StructFieldOptions.Optional);
         }
@@ -96,6 +98,8 @@ public struct FragInputs
                 subscriptOptions : StructFieldOptions.Optional);
             public static FieldDescriptor color = new FieldDescriptor(FragInputs.name, "color", "", ShaderValueType.Float4,
                 subscriptOptions : StructFieldOptions.Optional);
+            public static FieldDescriptor primitiveID = new FieldDescriptor(FragInputs.name, "primitiveID", "", ShaderValueType.Uint,
+                subscriptOptions: StructFieldOptions.Optional);
             public static FieldDescriptor IsFrontFace = new FieldDescriptor(FragInputs.name, "isFrontFace", "", ShaderValueType.Boolean,
                 subscriptOptions : StructFieldOptions.Optional);
         }

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/HDStructs.cs

@@ -41,6 +41,7 @@ static class HDStructs
                 HDStructFields.VaryingsMeshToPS.texCoord3,
                 HDStructFields.VaryingsMeshToPS.color,
                 HDStructFields.VaryingsMeshToPS.instanceID,
+                HDStructFields.VaryingsMeshToPS.primitiveID,
                 HDStructFields.VaryingsMeshToPS.cullFace,
             }
         };

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/HDTarget.cs

@@ -407,6 +407,7 @@ static class CoreFieldDependencies
             new FieldDependency(HDStructFields.FragInputs.texCoord2,                                 HDStructFields.VaryingsMeshToPS.texCoord2),
             new FieldDependency(HDStructFields.FragInputs.texCoord3,                                 HDStructFields.VaryingsMeshToPS.texCoord3),
             new FieldDependency(HDStructFields.FragInputs.color,                                     HDStructFields.VaryingsMeshToPS.color),
+            new FieldDependency(HDStructFields.FragInputs.primitiveID,                               HDStructFields.VaryingsMeshToPS.primitiveID),
             new FieldDependency(HDStructFields.FragInputs.IsFrontFace,                               HDStructFields.VaryingsMeshToPS.cullFace),
         };
 

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/Templates/SharedCode.template.hlsl

@@ -17,6 +17,10 @@ FragInputs BuildFragInputs(VaryingsMeshToPS input)
     $FragInputs.texCoord3:          output.texCoord3 = input.texCoord3;
     $FragInputs.color:              output.color = input.color;
 
+    #if defined(PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER) && defined(SHADER_STAGE_FRAGMENT) && (defined(VARYINGS_NEED_PRIMITIVEID) || (SHADERPASS == SHADERPASS_FULLSCREEN_DEBUG))
+    output.primitiveID = input.primitiveID;
+    #endif
+
     #if defined(VARYINGS_NEED_CULLFACE) && SHADER_STAGE_FRAGMENT
     output.isFrontFace = IS_FRONT_VFACE(input.cullFace, true, false);
     #endif

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/FragInputs.hlsl

@@ -26,6 +26,8 @@ struct FragInputs
     // When not using surface gradient, each vector of tangentToWorld are normalize (TODO: Maybe they should not even in case of no surface gradient ? Ask Morten)
     float3x3 tangentToWorld;
 
+    uint primitiveID; // Only with fullscreen pass debug currently - not supported on all platforms
+
     // For two sided lighting
     bool isFrontFace;
 };

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/ShaderPassFullScreenDebug.hlsl

@@ -31,21 +31,17 @@ PackedVaryingsToPS VertTesselation(VaryingsToDS input)
 #if !defined(_DEPTHOFFSET_ON)
 [earlydepthstencil] // quad overshading debug mode writes to UAV
 #endif
-void Frag(
-#ifdef PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER
-    uint primitiveID : SV_PrimitiveID, // Must be declare before FRONT_FACE_SEMANTIC
-#endif
-    PackedVaryingsToPS packedInput)
+void Frag(PackedVaryingsToPS packedInput)
 {
     UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(packedInput);
     FragInputs input = UnpackVaryingsMeshToFragInputs(packedInput.vmesh);
 
     PositionInputs posInput = GetPositionInput(input.positionSS.xy, _ScreenSize.zw, input.positionSS.z, input.positionSS.w, input.positionRWS.xyz);
 
+#ifdef PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER
     if (_DebugFullScreenMode == FULLSCREENDEBUGMODE_QUAD_OVERDRAW)
     {
-#ifdef PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER
-        IncrementQuadOverdrawCounter(posInput.positionSS.xy, primitiveID);
-#endif
+        IncrementQuadOverdrawCounter(posInput.positionSS.xy, input.primitiveID);
     }
+#endif
 }

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/VaryingMesh.hlsl

@@ -85,7 +85,18 @@ struct PackedVaryingsMeshToPS
     float4 interpolators5 : TEXCOORD5;
 #endif
 
-    UNITY_VERTEX_INPUT_INSTANCE_ID // Must be declare before FRONT_FACE_SEMANTIC
+    // In order to compile on all HDRP target platform we need to respect the following order for semantic:
+    // - SV_RenderTargetArrayIndex  // use for stereo instancing - Must be declare before SV_IsFrontFace
+    // - SV_PrimitiveID // Must be declare before SV_IsFrontFace and after SV_RenderTargetArrayIndex
+    // - SV_IsFrontFace 
+
+    UNITY_VERTEX_INPUT_INSTANCE_ID
+
+#ifdef PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER
+#if (defined(VARYINGS_NEED_PRIMITIVEID) || (SHADERPASS == SHADERPASS_FULLSCREEN_DEBUG)) && SHADER_STAGE_FRAGMENT
+    uint primitiveID : SV_PrimitiveID;
+#endif
+#endif
 
 #if defined(VARYINGS_NEED_CULLFACE) && SHADER_STAGE_FRAGMENT
     FRONT_FACE_TYPE cullFace : FRONT_FACE_SEMANTIC;
@@ -169,6 +180,12 @@ FragInputs UnpackVaryingsMeshToFragInputs(PackedVaryingsMeshToPS input)
     output.color = input.interpolators5;
 #endif
 
+#ifdef PLATFORM_SUPPORTS_PRIMITIVE_ID_IN_PIXEL_SHADER
+#if (defined(VARYINGS_NEED_PRIMITIVEID) || (SHADERPASS == SHADERPASS_FULLSCREEN_DEBUG)) && SHADER_STAGE_FRAGMENT
+    output.primitiveID = input.primitiveID;
+#endif
+#endif
+
 #if defined(VARYINGS_NEED_CULLFACE) && SHADER_STAGE_FRAGMENT
     output.isFrontFace = IS_FRONT_VFACE(input.cullFace, true, false);
 #endif