Remove BLEND keywords and replace with constant branch

TestProjects/HDRP_Tests/Assets/GraphicTests/Scenes/2x_Lighting/2208_And_2209_Reflection_Stencil/StencilShowShader.shader

@@ -88,7 +88,6 @@ Shader "Custom/StencilShowShader"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 
     //enable GPU instancing support

TestProjects/HDRP_Tests/Assets/GraphicTests/Scenes/2x_Lighting/2208_And_2209_Reflection_Stencil/StencilWriteShader.shader

@@ -88,7 +88,6 @@ Shader "Custom/StencilWriteShader"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 
     //enable GPU instancing support

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

@@ -169,6 +169,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Improve performance of GPU light AABB generation
 - Removed the max clamp value for the RTR, RTAO and RTGI's ray length (case 1279849).
 - Meshes assigned with a decal material are not visible anymore in ray-tracing or path-tracing.
+- Removed BLEND shader keywords.
 
 ## [10.0.0] - 2019-06-10
 

com.unity.render-pipelines.high-definition/Documentation~/Upgrading-from-2020.1-to-2020.2.md

@@ -166,11 +166,23 @@ to:
 For example, the call in the Lit shader has been updated to:
 `float4 preLD = SampleEnv(lightLoopContext, lightData.envIndex, R, PerceptualRoughnessToMipmapLevel(preLightData.iblPerceptualRoughness), lightData.rangeCompressionFactorCompensation, posInput.positionNDC);`
 
+From 10.x, the shader keywords _BLENDMODE_ALPHA _BLENDMODE_ADD and _BLENDMODE_PRE_MULTIPLY have been removed. They are no longer used and the property _Blendmode is used instead.
+For example in Material.hlsl, the following lines:
+```
+    #if defined(_BLENDMODE_ADD) || defined(_BLENDMODE_ALPHA)
+        return float4(diffuseLighting * opacity + specularLighting, opacity);
+```
+is replace by 
+```
+    if (_BlendMode == BLENDMODE_ALPHA || _BlendMode == BLENDMODE_ADDITIVE)
+        return float4(diffuseLighting * opacity + specularLighting, opacity);
+```
+This reduced the number of shader variant. In case of custom shader it can be required to move the include of Material.hlsl after the declaration of the property _Blendmode.
+
 From 10.x, HDRP includes a new optimization for [Planar Reflection Probes](Planar-Reflection-Probe.md). Now, when a shader samples a probe's environment map, it samples from mip level 0 if the LightData.roughReflections parameter is enabled (has a value of 1.0). You must update your custom shaders to take this behavior into account.
 For example, the call in the Lit shader has been updated to:
 `float4 preLD = SampleEnv(lightLoopContext, lightData.envIndex, R, PerceptualRoughnessToMipmapLevel(preLightData.iblPerceptualRoughness) * lightData.roughReflections, lightData.rangeCompressionFactorCompensation, posInput.positionNDC);`
 
-
 ## Raytracing
 
 From Unity 2020.2, the Raytracing Node in shader graph now apply the raytraced path (previously low path) to all raytraced effects but path tracing.

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/FBXArnoldSurfaceMaterialDescriptionPreprocessor.cs

@@ -104,11 +104,11 @@ void CreateFromMayaArnoldStandardSurfaceMaterial(MaterialDescription description
 
                 material.SetInt("_SrcBlend", 1);
                 material.SetInt("_DstBlend", 10);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = 3000;
             }
             else
@@ -209,11 +209,11 @@ void CreateFrom3DsMaxArnoldStandardSurfaceMaterial(MaterialDescription descripti
 
                 material.SetInt("_SrcBlend", 1);
                 material.SetInt("_DstBlend", 10);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = 3000;
             }
             else

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/FBXMaterialDescriptionPostprocessor.cs

@@ -81,11 +81,11 @@ public void OnPreprocessMaterialDescription(MaterialDescription description, Mat
                 material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                 material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                 material.SetInt("_ZWrite", 0);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Transparent;
             }
             else

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/PhysicalMaterial3DsMaxPreprocessor.cs

@@ -210,11 +210,11 @@ void CreateFrom3DsPhysicalMaterial(MaterialDescription description, Material mat
 
                 material.SetInt("_SrcBlend", 1);
                 material.SetInt("_DstBlend", 10);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = 3000;
             }
             else

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/SketchupMaterialDescriptionPostprocessor.cs

@@ -66,11 +66,11 @@ public void OnPreprocessMaterialDescription(MaterialDescription description, Mat
                 material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                 material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                 material.SetInt("_ZWrite", 0);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Transparent;
             }
             else

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/ThreeDSMaterialDescriptionPostprocessor.cs

@@ -59,11 +59,11 @@ public void OnPreprocessMaterialDescription(MaterialDescription description, Mat
                 material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                 material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                 material.SetInt("_ZWrite", 0);
+                material.SetFloat("_BlendMode", (float)BlendMode.Alpha);
                 material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                 material.EnableKeyword("_SURFACE_TYPE_TRANSPARENT");
                 material.EnableKeyword("_BLENDMODE_PRESERVE_SPECULAR_LIGHTING");
                 material.EnableKeyword("_ENABLE_FOG_ON_TRANSPARENT");
-                material.EnableKeyword("_BLENDMODE_ALPHA");
                 material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Transparent;
             }
             else

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

@@ -855,7 +855,6 @@ static class CoreDefines
     static class CoreIncludes
     {
         // CorePregraph
-        public const string kTextureStack = "Packages/com.unity.render-pipelines.core/ShaderLibrary/TextureStack.hlsl";
         public const string kShaderVariables = "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/ShaderVariables.hlsl";
         public const string kFragInputs = "Packages/com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/FragInputs.hlsl";
         public const string kMaterial = "Packages/com.unity.render-pipelines.high-definition/Runtime/Material/Material.hlsl";
@@ -933,22 +932,14 @@ static class CoreIncludes
 
         public static IncludeCollection CorePregraph = new IncludeCollection
         {
-            { kTextureStack, IncludeLocation.Pregraph },        // TODO: put this on a conditional
-            { kShaderVariables, IncludeLocation.Pregraph },
-            { kFragInputs, IncludeLocation.Pregraph },
             { kDebugDisplay, IncludeLocation.Pregraph },            
             { kMaterial, IncludeLocation.Pregraph },
         };
 
         public static IncludeCollection RaytracingCorePregraph = new IncludeCollection
         {
             // Pregraph includes
-            { CoreIncludes.kTextureStack, IncludeLocation.Pregraph },
-            { CoreIncludes.kFragInputs, IncludeLocation.Pregraph },
-
-            // Ray Tracing macros should be included before shader variables to guarantee that the macros are overriden
             { CoreIncludes.kRaytracingMacros, IncludeLocation.Pregraph },
-            { CoreIncludes.kShaderVariables, IncludeLocation.Pregraph },
             { CoreIncludes.kMaterial, IncludeLocation.Pregraph },
             { CoreIncludes.kShaderVariablesRaytracing, IncludeLocation.Pregraph },
             { CoreIncludes.kShaderVariablesRaytracingLightLoop, IncludeLocation.Pregraph },

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

@@ -25,7 +25,10 @@ Pass
     $splice(GraphKeywords)
 
     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl"
+    #include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/ShaderVariables.hlsl"
+    #include "Packages/com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/FragInputs.hlsl"
     #include "Packages/com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/ShaderPass/ShaderPass.cs.hlsl"
+    #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/TextureStack.hlsl" // Required to be include before we include properties as it define DECLARE_STACK_CB
 
     // --------------------------------------------------
     // Defines
@@ -108,17 +111,22 @@ Pass
     // Dots Instancing
     $splice(DotsInstancingOptions)
 
+    // Various properties
+
     $splice(HybridV1InjectedBuiltinProperties)
 
-    // Includes
-    $splice(PreGraphIncludes)
+    // -- Graph Properties
+    $splice(GraphProperties)
 
-    // Properties used by SceneSelectionPass
+    // -- Properties used by SceneSelectionPass
     #ifdef SCENESELECTIONPASS
     int _ObjectId;
     int _PassValue;
     #endif
 
+    // Includes
+    $splice(PreGraphIncludes)
+
     // --------------------------------------------------
     // Structs and Packing
 
@@ -129,8 +137,6 @@ Pass
     // --------------------------------------------------
     // Graph
 
-    // Graph Properties
-    $splice(GraphProperties)
 
     // Graph Functions
     $splice(GraphFunctions)

com.unity.render-pipelines.high-definition/Editor/Material/Unlit/BaseUnlitGUI.cs

@@ -38,11 +38,6 @@ public static void SetupBaseUnlitKeywords(this Material material)
             bool transparentWritesMotionVec = (surfaceType == SurfaceType.Transparent) && material.HasProperty(kTransparentWritingMotionVec) && material.GetInt(kTransparentWritingMotionVec) > 0;
             CoreUtils.SetKeyword(material, "_TRANSPARENT_WRITES_MOTION_VEC", transparentWritesMotionVec);
 
-            // These need to always been set either with opaque or transparent! So a users can switch to opaque and remove the keyword correctly
-            CoreUtils.SetKeyword(material, "_BLENDMODE_ALPHA", false);
-            CoreUtils.SetKeyword(material, "_BLENDMODE_ADD", false);
-            CoreUtils.SetKeyword(material, "_BLENDMODE_PRE_MULTIPLY", false);
-
             HDRenderQueue.RenderQueueType renderQueueType = HDRenderQueue.GetTypeByRenderQueueValue(material.renderQueue);
             bool needOffScreenBlendFactor = renderQueueType == HDRenderQueue.RenderQueueType.AfterPostprocessTransparent || renderQueueType == HDRenderQueue.RenderQueueType.LowTransparent;
 
@@ -93,10 +88,6 @@ public static void SetupBaseUnlitKeywords(this Material material)
                 {
                     BlendMode blendMode = material.GetBlendMode();
 
-                    CoreUtils.SetKeyword(material, "_BLENDMODE_ALPHA", BlendMode.Alpha == blendMode);
-                    CoreUtils.SetKeyword(material, "_BLENDMODE_ADD", BlendMode.Additive == blendMode);
-                    CoreUtils.SetKeyword(material, "_BLENDMODE_PRE_MULTIPLY", BlendMode.Premultiply == blendMode);
-
                     // When doing off-screen transparency accumulation, we change blend factors as described here: https://developer.nvidia.com/gpugems/GPUGems3/gpugems3_ch23.html
                     switch (blendMode)
                     {

com.unity.render-pipelines.high-definition/Editor/VFXGraph/Outputs/VFXAbstractParticleHDRPLitOutput.cs

@@ -428,18 +428,7 @@ public override IEnumerable<KeyValuePair<string, VFXShaderWriter>> additionalRep
                 var forwardDefines = new VFXShaderWriter();
                 forwardDefines.WriteLine("#define _ENABLE_FOG_ON_TRANSPARENT");
                 forwardDefines.WriteLine("#define _DISABLE_DECALS");
-                switch (blendMode)
-                {
-                    case BlendMode.Alpha:
-                        forwardDefines.WriteLine("#define _BLENDMODE_ALPHA");
-                        break;
-                    case BlendMode.Additive:
-                        forwardDefines.WriteLine("#define _BLENDMODE_ADD");
-                        break;
-                    case BlendMode.AlphaPremultiplied:
-                        forwardDefines.WriteLine("#define _BLENDMODE_PRE_MULTIPLY");
-                        break;
-                }
+
                 if (!isBlendModeOpaque)
                 {
                     if (preserveSpecularLighting)

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

@@ -120,7 +120,7 @@ Shader "HDRP/AxF"
 
 
 //      [ToggleUI] _EnableFogOnTransparent("Enable Fog", Float) = 1.0
-//      [ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
+//      [HideInInspector][ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
 
         [ToggleUI] _DoubleSidedEnable("Double sided enable", Float) = 0.0
         [Enum(Flip, 0, Mirror, 1, None, 2)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1 // This is for the editor only, see BaseLitUI.cs: _DoubleSidedConstants will be set based on the mode.
@@ -180,7 +180,6 @@ Shader "HDRP/AxF"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _BLENDMODE_PRESERVE_SPECULAR_LIGHTING // easily handled in material.hlsl, so adding this already.
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 

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

@@ -120,6 +120,7 @@ float _AlphaCutoff;
 float _UseShadowThreshold;
 float _AlphaCutoffShadow;
 float4 _DoubleSidedConstants;
+float _BlendMode;
 
 // Specular AA
 float _EnableGeometricSpecularAA;

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

@@ -458,7 +458,6 @@ Shader "HDRP/LayeredLit"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 

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

@@ -466,7 +466,6 @@ Shader "HDRP/LayeredLitTessellation"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 

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

@@ -289,7 +289,6 @@ Shader "HDRP/Lit"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
     #pragma shader_feature_local _TRANSPARENT_WRITES_MOTION_VEC

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

@@ -112,6 +112,7 @@ float _DistortionVectorBias;
 float _DistortionBlurScale;
 float _DistortionBlurRemapMin;
 float _DistortionBlurRemapMax;
+float _BlendMode;
 
 float _PPDMaxSamples;
 float _PPDMinSamples;

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

@@ -297,7 +297,6 @@ Shader "HDRP/LitTessellation"
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature_local _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature_local _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature_local _ENABLE_FOG_ON_TRANSPARENT
 
@@ -357,6 +356,8 @@ Shader "HDRP/LitTessellation"
     // LitShading.hlsl implements the light loop API.
     // LitData.hlsl is included here, LitShading.hlsl is included below for shading passes only.
 
+    #include "Packages/com.unity.render-pipelines.high-definition/Runtime/Material/Material.hlsl"
+
     ENDHLSL
 
     SubShader