HDRenderPipeline: Remove multiply blend mode

- Multiply make it easy to do mistake (inf, negative number, NaN) and
prevent optimization like half res rendering or offscreen compositing

ScriptableRenderPipeline/HDRenderPipeline/Material/LayeredLit/LayeredLit.shader

 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_MULTIPLY _BLENDMODE_PRE_MULTIPLY
+    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
 
             #pragma multi_compile USE_FPTL_LIGHTLIST USE_CLUSTERED_LIGHTLIST
 
             #define SHADERPASS SHADERPASS_FORWARD
-            #include "../../ShaderVariables.hlsl"          
+            #include "../../ShaderVariables.hlsl"
             #include "../../Lighting/Lighting.hlsl"
             #include "../Lit/ShaderPass/LitSharePass.hlsl"
             #include "LayeredLitData.hlsl"

ScriptableRenderPipeline/HDRenderPipeline/Material/LayeredLit/LayeredLitTessellation.shader

 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_MULTIPLY _BLENDMODE_PRE_MULTIPLY
+    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
 

ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/Lit.shader

 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_MULTIPLY _BLENDMODE_PRE_MULTIPLY
+    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
 

ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitTessellation.shader

 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_MULTIPLY _BLENDMODE_PRE_MULTIPLY
+    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature _BLENDMODE_PRESERVE_SPECULAR_LIGHTING
     #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
 

ScriptableRenderPipeline/HDRenderPipeline/Material/Material.hlsl

 // There is a set of Material Keyword that a HD shaders must define (or not define). We call them system KeyWord.
 // .Shader need to define:
 // - _SURFACE_TYPE_TRANSPARENT if they use a transparent material
-// - _BLENDMODE_ALPHA, _BLENDMODE_ADD, _BLENDMODE_MULTIPLY, _BLENDMODE_PRE_MULTIPLY for blend mode
+// - _BLENDMODE_ALPHA, _BLENDMODE_ADD, _BLENDMODE_PRE_MULTIPLY for blend mode
 // - _BLENDMODE_PRESERVE_SPECULAR_LIGHTING for correct lighting when blend mode are use with a Lit material
 // - _ENABLE_FOG_ON_TRANSPARENT if fog is enable on transparent surface
 
     // However this have precision issue when reaching 0, so we change the blend mode and apply src * src_a inside the shader instead
     #if defined(_BLENDMODE_ADD) || defined(_BLENDMODE_ALPHA)
     return float4(diffuseLighting * opacity + specularLighting, opacity);
-    #else // defined(_BLENDMODE_MULTIPLY) || defined(_BLENDMODE_PRE_MULTIPLY)
+    #else // defined(_BLENDMODE_PRE_MULTIPLY)
-    #else // defined(_BLENDMODE_MULTIPLY) || defined(_BLENDMODE_PRE_MULTIPLY)
+    #else // defined(_BLENDMODE_PRE_MULTIPLY)
     return float4(diffuseLighting + specularLighting, opacity);
     #endif
 #endif
     #elif defined(_BLENDMODE_ADD)
     // For additive, we just need to fade to black with fog density (black + background == background color == fog color)
     result.rgb = result.rgb * (1.0 - fog.a);
-    #elif defined(_BLENDMODE_MULTIPLY)
-    // For multiplicative, we just need to fade to white with fog density (white * background == background color == fog color)
-    result.rgb = lerp(result.rgb, float3(1.0, 1.0, 1.0), fog.a);
     #elif defined(_BLENDMODE_PRE_MULTIPLY)
     // For Pre-Multiplied Alpha Blend, we need to multiply fog color by src alpha to match regular alpha blending formula.
     result.rgb = lerp(result.rgb, fog.rgb * result.a, fog.a);

ScriptableRenderPipeline/HDRenderPipeline/Material/Unlit/Editor/BaseUnlitUI.cs

         {
             Alpha = 0,
             Additive = 1,
-            Multiplicative = 3,
             PremultipliedAlpha = 4
         }
 
         protected const string kEnableFogOnTransparent = "_EnableFogOnTransparent";
         protected MaterialProperty enableBlendModePreserveSpecularLighting = null;
         protected const string kEnableBlendModePreserveSpecularLighting = "_EnableBlendModePreserveSpecularLighting";
-        
+
 
         // See comment in LitProperties.hlsl
         const string kEmissionColor = "_EmissionColor";
             preRefractionPass = FindProperty(kPreRefractionPass, props, false);
 
             enableFogOnTransparent = FindProperty(kEnableFogOnTransparent, props, false);
-            enableBlendModePreserveSpecularLighting = FindProperty(kEnableBlendModePreserveSpecularLighting, props, false);            
+            enableBlendModePreserveSpecularLighting = FindProperty(kEnableBlendModePreserveSpecularLighting, props, false);
         }
 
         void SurfaceTypePopup()
             // These need to always been set either with opaque or transparent! So a users can switch to opaque and remove the keyword correctly
             SetKeyword(material, "_BLENDMODE_ALPHA", false);
             SetKeyword(material, "_BLENDMODE_ADD", false);
-            SetKeyword(material, "_BLENDMODE_MULTIPLY", false);
             SetKeyword(material, "_BLENDMODE_PRE_MULTIPLY", false);
 
             if (surfaceType == SurfaceType.Opaque)
 
                     SetKeyword(material, "_BLENDMODE_ALPHA", BlendMode.Alpha == blendMode);
                     SetKeyword(material, "_BLENDMODE_ADD", BlendMode.Additive == blendMode);
-                    SetKeyword(material, "_BLENDMODE_MULTIPLY", BlendMode.Multiplicative == blendMode);
                     SetKeyword(material, "_BLENDMODE_PRE_MULTIPLY", BlendMode.PremultipliedAlpha == blendMode);
 
                     switch (blendMode)

ScriptableRenderPipeline/HDRenderPipeline/Material/Unlit/Unlit.shader

         // In our case we don't use such a mechanism but need to keep the code quiet. We declare the value and always enable it.
         // TODO: Fix the code in legacy unity so we can customize the beahvior for GI
         _EmissionColor("Color", Color) = (1, 1, 1)
-        
+
         // HACK: GI Baking system relies on some properties existing in the shader ("_MainTex", "_Cutoff" and "_Color") for opacity handling, so we need to store our version of those parameters in the hard-coded name the GI baking system recognizes.
         _MainTex("Albedo", 2D) = "white" {}
         _Color("Color", Color) = (1,1,1,1)
 
     // Keyword for transparent
     #pragma shader_feature _SURFACE_TYPE_TRANSPARENT
-    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_MULTIPLY _BLENDMODE_PRE_MULTIPLY
+    #pragma shader_feature _ _BLENDMODE_ALPHA _BLENDMODE_ADD _BLENDMODE_PRE_MULTIPLY
     #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
 
     //-------------------------------------------------------------------------------------

Tests/GraphicsTests/RenderPipeline/LightweightPipeline/Scenes/037_Particles/Scripts.meta

 fileFormatVersion: 2
-guid: e475c42352524461ca0371d90bbca97f
+guid: c6fe8859c4c681d428c024202d9f27b4
-timeCreated: 1509363645
-licenseType: Pro
 DefaultImporter:
   externalObjects: {}
   userData: