beginning work on decal shader

ScriptableRenderPipeline/HDRenderPipeline/HDRenderPipeline.cs

                 m_GbufferManager.SetBufferDescription(gbufferIndex, "_GBufferTexture" + gbufferIndex, rtFormat[gbufferIndex], rtReadWrite[gbufferIndex]);
             }
 
+			m_DbufferManager.gbufferCount = 1;
             m_DbufferManager.SetBufferDescription(0, "_DBufferTexture0", RenderTextureFormat.ARGB32, RenderTextureReadWrite.sRGB);
 
             m_VelocityBuffer = HDShaderIDs._VelocityTexture;
 
             using (new ProfilingSample(cmd, "Decals"))
             {
+				CoreUtils.SetRenderTarget(cmd, m_DbufferManager.GetGBuffers(), m_CameraDepthStencilBufferRT);
                 DecalSystem.instance.Render(renderContext, camera, cmd);
             }
 

ScriptableRenderPipeline/HDRenderPipeline/Material/Decal/Decal.shader

+Shader "HDRenderPipeline/Decal"
+{
+    Properties
+    {      
+        _BaseColorMap("BaseColorMap", 2D) = "white" {}     
+    }
+
+    HLSLINCLUDE
+
+    #pragma target 4.5
+    #pragma only_renderers d3d11 ps4 metal // TEMP: until we go futher in dev
+    //#pragma enable_d3d11_debug_symbols
+
+    //-------------------------------------------------------------------------------------
+    // Variant
+    //-------------------------------------------------------------------------------------
+/*
+    #pragma shader_feature _ALPHATEST_ON
+    #pragma shader_feature _DEPTHOFFSET_ON
+    #pragma shader_feature _DOUBLESIDED_ON
+    #pragma shader_feature _ _VERTEX_DISPLACEMENT _PIXEL_DISPLACEMENT
+    #pragma shader_feature _VERTEX_DISPLACEMENT_LOCK_OBJECT_SCALE
+    #pragma shader_feature _DISPLACEMENT_LOCK_TILING_SCALE
+    #pragma shader_feature _PIXEL_DISPLACEMENT_LOCK_OBJECT_SCALE
+    #pragma shader_feature _VERTEX_WIND
+    #pragma shader_feature _ _REFRACTION_PLANE _REFRACTION_SPHERE
+
+    #pragma shader_feature _ _MAPPING_PLANAR _MAPPING_TRIPLANAR
+    #pragma shader_feature _NORMALMAP_TANGENT_SPACE
+    #pragma shader_feature _ _REQUIRE_UV2 _REQUIRE_UV3
+
+    #pragma shader_feature _NORMALMAP
+    #pragma shader_feature _MASKMAP
+    #pragma shader_feature _BENTNORMALMAP
+    #pragma shader_feature _EMISSIVE_COLOR_MAP
+    #pragma shader_feature _ENABLESPECULAROCCLUSION
+    #pragma shader_feature _HEIGHTMAP
+    #pragma shader_feature _TANGENTMAP
+    #pragma shader_feature _ANISOTROPYMAP
+    #pragma shader_feature _DETAIL_MAP
+    #pragma shader_feature _SUBSURFACE_RADIUS_MAP
+    #pragma shader_feature _THICKNESSMAP
+    #pragma shader_feature _SPECULARCOLORMAP
+
+    // 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_PRESERVE_SPECULAR_LIGHTING
+    #pragma shader_feature _ENABLE_FOG_ON_TRANSPARENT
+
+    // MaterialId are used as shader feature to allow compiler to optimize properly
+    // Note _MATID_STANDARD is not define as there is always the default case "_". We assign default as _MATID_STANDARD, so we never test _MATID_STANDARD
+    #pragma shader_feature _ _MATID_SSS _MATID_ANISO _MATID_SPECULAR _MATID_CLEARCOAT
+
+    #pragma multi_compile LIGHTMAP_OFF LIGHTMAP_ON
+    #pragma multi_compile DIRLIGHTMAP_OFF DIRLIGHTMAP_COMBINED
+    #pragma multi_compile DYNAMICLIGHTMAP_OFF DYNAMICLIGHTMAP_ON
+    // enable dithering LOD crossfade
+    #pragma multi_compile _ LOD_FADE_CROSSFADE
+    // TODO: We should have this keyword only if VelocityInGBuffer is enable, how to do that ?
+    //#pragma multi_compile VELOCITYOUTPUT_OFF VELOCITYOUTPUT_ON
+*/
+
+
+    //-------------------------------------------------------------------------------------
+    // Define
+    //-------------------------------------------------------------------------------------
+/*
+    #define UNITY_MATERIAL_LIT // Need to be define before including Material.hlsl
+    // Use surface gradient normal mapping as it handle correctly triplanar normal mapping and multiple UVSet
+    #define SURFACE_GRADIENT
+    // This shader support vertex modification
+    #define HAVE_VERTEX_MODIFICATION
+*/
+    //-------------------------------------------------------------------------------------
+    // Include
+    //-------------------------------------------------------------------------------------
+
+
+    #include "../../../Core/ShaderLibrary/Common.hlsl"
+
+//    #include "../../../Core/ShaderLibrary/Wind.hlsl"
+    #include "../../ShaderPass/FragInputs.hlsl"
+//    #include "../../ShaderPass/ShaderPass.cs.hlsl"
+
+
+    //-------------------------------------------------------------------------------------
+    // variable declaration
+    //-------------------------------------------------------------------------------------
+
+    #include "DecalProperties.hlsl"
+
+    // All our shaders use same name for entry point
+    #pragma vertex Vert
+    #pragma fragment Frag
+
+    ENDHLSL
+
+    SubShader
+    {
+        Pass
+        {
+            Name "DBuffer"  // Name is not used
+            Tags { "LightMode" = "GBuffer" } // This will be only for opaque object based on the RenderQueue index
+
+            Cull [_CullMode]
+
+            Stencil
+            {
+                Ref  [_StencilRef]
+                Comp Always
+                Pass Replace
+            }
+
+            HLSLPROGRAM
+			#define SHADERPASS_DBUFFER
+
+            #include "../../ShaderVariables.hlsl"
+			#include "OutputBuffers.hlsl"
+//            #include "../../Material/Material.hlsl"
+//            #include "ShaderPass/LitSharePass.hlsl"
+//            #include "LitData.hlsl"
+			#include "../../ShaderPass/VaryingMesh.hlsl"
+            #include "ShaderPass/ShaderPassDBuffer.hlsl"
+
+            ENDHLSL
+        }
+	}
+//    CustomEditor "Experimental.Rendering.HDPipeline.LitGUI"
+}

ScriptableRenderPipeline/HDRenderPipeline/Material/Decal/DecalProperties.hlsl

+#ifndef UNITY_DECALPROPERTIES_INCLUDED
+#define UNITY_DECALPROPERTIES_INCLUDED
+
+
+TEXTURE2D(_BaseColorMap);
+SAMPLER2D(sampler_BaseColorMap);
+
+#endif 

ScriptableRenderPipeline/HDRenderPipeline/Material/Decal/OutputBuffers.hlsl

+#ifndef UNITY_DECALOUTPUTBUFFERS_INCLUDED
+#define UNITY_DECALOUTPUTBUFFERS_INCLUDED
+
+#define DBufferType0 uint4
+
+#define OUTPUT_DBUFFER(NAME)                            \
+        out DBufferType0 MERGE_NAME(NAME, 0) : SV_Target0
+
+#endif 

ScriptableRenderPipeline/HDRenderPipeline/Material/Decal/ShaderPass/ShaderPassDBuffer.hlsl

+#if SHADERPASS != SHADERPASS_GBUFFER
+#error SHADERPASS_is_not_correctly_define
+#endif
+
+#include "..\..\ShaderPass\VertMesh.hlsl"
+
+PackedVaryingsType Vert(AttributesMesh inputMesh)
+{
+    VaryingsType varyingsType;
+    varyingsType.vmesh = VertMesh(inputMesh);
+    return PackVaryingsType(varyingsType);
+}
+
+
+void Frag(  PackedVaryingsToPS packedInput,
+            OUTPUT_DBUFFER(outDBuffer)            
+            )
+{
+/*	
+    FragInputs input = UnpackVaryingsMeshToFragInputs(packedInput.vmesh);
+
+    // input.unPositionSS is SV_Position
+    PositionInputs posInput = GetPositionInput(input.unPositionSS.xy, _ScreenSize.zw);
+    UpdatePositionInput(input.unPositionSS.z, input.unPositionSS.w, input.positionWS, posInput);
+    float3 V = GetWorldSpaceNormalizeViewDir(input.positionWS);
+
+    SurfaceData surfaceData;
+    BuiltinData builtinData;
+    GetSurfaceAndBuiltinData(input, V, posInput, surfaceData, builtinData);
+
+    BSDFData bsdfData = ConvertSurfaceDataToBSDFData(surfaceData);
+
+    PreLightData preLightData = GetPreLightData(V, posInput, bsdfData);
+
+    float3 bakeDiffuseLighting = GetBakedDiffuseLigthing(surfaceData, builtinData, bsdfData, preLightData);
+
+    ENCODE_INTO_GBUFFER(surfaceData, bakeDiffuseLighting, outGBuffer);
+    ENCODE_VELOCITY_INTO_GBUFFER(builtinData.velocity, outVelocityBuffer);
+*/
+	outDBuffer0.rgba = uint4(255,0,0,255);
+}