Refactor material shaders generator to use modular features as extensions

Content/Editor/MaterialTemplates/Features/Distortion.hlsl

@@ -0,0 +1,50 @@
+// Copyright (c) 2012-2021 Wojciech Figat. All rights reserved.
+
+@0// Distortion: Defines
+@1// Distortion: Includes
+@2// Distortion: Constants
+@3// Distortion: Resources
+@4// Distortion: Utilities
+@5// Distortion: Shaders
+#if USE_DISTORTION
+
+// Pixel Shader function for Distortion Pass
+META_PS(USE_DISTORTION, FEATURE_LEVEL_ES2)
+float4 PS_Distortion(PixelInput input) : SV_Target0
+{
+#if USE_DITHERED_LOD_TRANSITION
+	// LOD masking
+	ClipLODTransition(input);
+#endif
+
+	// Get material parameters
+	MaterialInput materialInput = GetMaterialInput(input);
+	Material material = GetMaterialPS(materialInput);
+
+	// Masking
+#if MATERIAL_MASKED
+	clip(material.Mask - MATERIAL_MASK_THRESHOLD);
+#endif
+
+	float3 viewNormal = normalize(TransformWorldVectorToView(materialInput, material.WorldNormal));
+	float airIOR = 1.0f;
+#if USE_PIXEL_NORMAL_OFFSET_REFRACTION
+	float3 viewVertexNormal = TransformWorldVectorToView(materialInput, TransformTangentVectorToWorld(materialInput, float3(0, 0, 1)));
+	float2 distortion = (viewVertexNormal.xy - viewNormal.xy) * (material.Refraction - airIOR);
+#else
+	float2 distortion = viewNormal.xy * (material.Refraction - airIOR);
+#endif
+
+	// Clip if the distortion distance (squared) is too small to be noticed
+	clip(dot(distortion, distortion) - 0.00001);
+
+	// Scale up for better precision in low/subtle refractions at the expense of artefacts at higher refraction
+	distortion *= 4.0f;
+	
+	// Use separate storage for positive and negative offsets
+	float2 addOffset = max(distortion, 0);
+	float2 subOffset = abs(min(distortion, 0));
+	return float4(addOffset.x, addOffset.y, subOffset.x, subOffset.y);
+}
+
+#endif

Content/Editor/MaterialTemplates/Particle.shader

@@ -802,44 +802,6 @@ float4 PS_Forward(PixelInput input) : SV_Target0
 	return output;
 }
 
-#if USE_DISTORTION
-
-// Pixel Shader function for Distortion Pass
-META_PS(USE_DISTORTION, FEATURE_LEVEL_ES2)
-float4 PS_Distortion(PixelInput input) : SV_Target0
-{
-	// Get material parameters
-	MaterialInput materialInput = GetMaterialInput(input);
-	Material material = GetMaterialPS(materialInput);
-
-	// Masking
-#if MATERIAL_MASKED
-	clip(material.Mask - MATERIAL_MASK_THRESHOLD);
-#endif
-
-	float3 viewNormal = normalize(TransformWorldVectorToView(materialInput, material.WorldNormal));
-	float airIOR = 1.0f;
-#if USE_PIXEL_NORMAL_OFFSET_REFRACTION
-	float3 viewVertexNormal = TransformWorldVectorToView(materialInput, TransformTangentVectorToWorld(materialInput, float3(0, 0, 1)));
-	float2 distortion = (viewVertexNormal.xy - viewNormal.xy) * (material.Refraction - airIOR);
-#else
-	float2 distortion = viewNormal.xy * (material.Refraction - airIOR);
-#endif
-
-	// Clip if the distortion distance (squared) is too small to be noticed
-	clip(dot(distortion, distortion) - 0.00001);
-
-	// Scale up for better precision in low/subtle refractions at the expense of artefacts at higher refraction
-	distortion *= 4.0f;
-
-	// Use separate storage for positive and negative offsets
-	float2 addOffset = max(distortion, 0);
-	float2 subOffset = abs(min(distortion, 0));
-	return float4(addOffset.x, addOffset.y, subOffset.x, subOffset.y);
-}
-
-#endif
-
 // Pixel Shader function for Depth Pass
 META_PS(true, FEATURE_LEVEL_ES2)
 void PS_Depth(PixelInput input

Content/Editor/MaterialTemplates/SurfaceForward.shader

@@ -562,12 +562,6 @@ void ClipLODTransition(PixelInput input)
 	}
 }
 
-#else
-
-void ClipLODTransition(PixelInput input)
-{
-}
-
 #endif
 
 // Pixel Shader function for Forward Pass
@@ -576,9 +570,11 @@ float4 PS_Forward(PixelInput input) : SV_Target0
 {
 	float4 output = 0;
 
+#if USE_DITHERED_LOD_TRANSITION
 	// LOD masking
 	ClipLODTransition(input);
 	// TODO: make model LOD transition smoother for transparent materials by using opacity to reduce aliasing
+#endif
 
 	// Get material parameters
 	MaterialInput materialInput = GetMaterialInput(input);
@@ -665,47 +661,6 @@ float4 PS_Forward(PixelInput input) : SV_Target0
 	return output;
 }
 
-#if USE_DISTORTION
-
-// Pixel Shader function for Distortion Pass
-META_PS(USE_DISTORTION, FEATURE_LEVEL_ES2)
-float4 PS_Distortion(PixelInput input) : SV_Target0
-{
-	// LOD masking
-	ClipLODTransition(input);
-
-	// Get material parameters
-	MaterialInput materialInput = GetMaterialInput(input);
-	Material material = GetMaterialPS(materialInput);
-
-	// Masking
-#if MATERIAL_MASKED
-	clip(material.Mask - MATERIAL_MASK_THRESHOLD);
-#endif
-
-	float3 viewNormal = normalize(TransformWorldVectorToView(materialInput, material.WorldNormal));
-	float airIOR = 1.0f;
-#if USE_PIXEL_NORMAL_OFFSET_REFRACTION
-	float3 viewVertexNormal = TransformWorldVectorToView(materialInput, TransformTangentVectorToWorld(materialInput, float3(0, 0, 1)));
-	float2 distortion = (viewVertexNormal.xy - viewNormal.xy) * (material.Refraction - airIOR);
-#else
-	float2 distortion = viewNormal.xy * (material.Refraction - airIOR);
-#endif
-
-	// Clip if the distortion distance (squared) is too small to be noticed
-	clip(dot(distortion, distortion) - 0.00001);
-
-	// Scale up for better precision in low/subtle refractions at the expense of artefacts at higher refraction
-	distortion *= 4.0f;
-	
-	// Use separate storage for positive and negative offsets
-	float2 addOffset = max(distortion, 0);
-	float2 subOffset = abs(min(distortion, 0));
-	return float4(addOffset.x, addOffset.y, subOffset.x, subOffset.y);
-}
-
-#endif
-
 // Pixel Shader function for Depth Pass
 META_PS(true, FEATURE_LEVEL_ES2)
 void PS_Depth(PixelInput input
@@ -714,8 +669,10 @@ void PS_Depth(PixelInput input
 #endif
 	)
 {
+#if USE_DITHERED_LOD_TRANSITION
 	// LOD masking
 	ClipLODTransition(input);
+#endif
 
 	// Get material parameters
 	MaterialInput materialInput = GetMaterialInput(input);

Source/Engine/Graphics/Materials/DeferredMaterialShader.cpp

@@ -70,8 +70,6 @@ void DeferredMaterialShader::Bind(BindParameters& params)
     int32 srv = 0;
 
     // Setup features
-    if (_info.TessellationMode != TessellationMethod::None)
-        TessellationFeature::Bind(params, cb, srv);
     const bool useLightmap = _info.BlendMode == MaterialBlendMode::Opaque && LightmapFeature::Bind(params, cb, srv);
 
     // Setup parameters

Source/Engine/Graphics/Materials/ForwardMaterialShader.cpp

@@ -79,8 +79,6 @@ void ForwardMaterialShader::Bind(BindParameters& params)
     int32 srv = 0;
 
     // Setup features
-    if (_info.TessellationMode != TessellationMethod::None)
-        TessellationFeature::Bind(params, cb, srv);
 
     // Setup parameters
     MaterialParameter::BindMeta bindMeta;

Source/Engine/Graphics/Materials/MaterialShaderFeatures.cpp

@@ -159,7 +159,7 @@ void TessellationFeature::Generate(GeneratorData& data)
 {
     data.Template = TEXT("Tessellation.hlsl");
     data.ConstantsSize = 0;
-    data.ResourcesCount = SRVs;
+    data.ResourcesCount = 0;
 }
 
 void LightmapFeature::Generate(GeneratorData& data)
@@ -169,4 +169,11 @@ void LightmapFeature::Generate(GeneratorData& data)
     data.ResourcesCount = SRVs;
 }
 
+void DistortionFeature::Generate(GeneratorData& data)
+{
+    data.Template = TEXT("Distortion.hlsl");
+    data.ConstantsSize = 0;
+    data.ResourcesCount = 0;
+}
+
 #endif

Source/Engine/Graphics/Materials/MaterialShaderFeatures.h

@@ -43,11 +43,6 @@ struct ForwardShadingFeature : MaterialShaderFeature
 // Material shader feature that adds geometry hardware tessellation (using Hull and Domain shaders).
 struct TessellationFeature : MaterialShaderFeature
 {
-    enum { SRVs = 0 };
-
-    static void Bind(MaterialShader::BindParameters& params, byte*& cb, int32& srv)
-    {
-    }
 #if USE_EDITOR
     static void Generate(GeneratorData& data);
 #endif
@@ -68,3 +63,11 @@ struct LightmapFeature : MaterialShaderFeature
     static void Generate(GeneratorData& data);
 #endif
 };
+
+// Material shader feature that adds distortion vectors rendering pass.
+struct DistortionFeature : MaterialShaderFeature
+{
+#if USE_EDITOR
+    static void Generate(GeneratorData& data);
+#endif
+};

Source/Engine/Graphics/Materials/ParticleMaterialShader.cpp

@@ -72,16 +72,23 @@ void ParticleMaterialShader::Bind(BindParameters& params)
     auto& view = params.RenderContext.View;
     auto cache = params.RenderContext.List;
     auto& drawCall = *params.FirstDrawCall;
+    const uint32 sortedIndicesOffset = drawCall.Particle.Module->SortedIndicesOffset;
     const auto cb0 = _shader->GetCB(0);
     const bool hasCb0 = cb0->GetSize() != 0;
+    ASSERT(hasCb0 && "TODO: fix it"); // TODO: always make cb pointer valid even if cb is missing
     const auto cb1 = _shader->GetCB(1);
-    const bool hasCb1 = cb1->GetSize() != 0;
+    const bool hasCb1 = cb1 && cb1->GetSize() != 0;
-    const uint32 sortedIndicesOffset = drawCall.Particle.Module->SortedIndicesOffset;
+    byte* cb = _cb0Data.Get();
+    auto materialData = reinterpret_cast<ParticleMaterialShaderData*>(cb);
+    cb += sizeof(ParticleMaterialShaderData);
+    int32 srv = 0;
+    
+    // Setup features
 
     // Setup parameters
     MaterialParameter::BindMeta bindMeta;
     bindMeta.Context = context;
-    bindMeta.Constants = hasCb0 ? _cb0Data.Get() + sizeof(ParticleMaterialShaderData) : nullptr;
+    bindMeta.Constants = cb;
     bindMeta.Input = nullptr;
     bindMeta.Buffers = params.RenderContext.Buffers;
     bindMeta.CanSampleDepth = GPUDevice::Instance->Limits.HasReadOnlyDepth;

Source/Engine/Graphics/Materials/TerrainMaterialShader.cpp

@@ -63,8 +63,6 @@ void TerrainMaterialShader::Bind(BindParameters& params)
     int32 srv = 3;
 
     // Setup features
-    if (_info.TessellationMode != TessellationMethod::None)
-        TessellationFeature::Bind(params, cb, srv);
     const bool useLightmap = LightmapFeature::Bind(params, cb, srv);
 
     // Setup parameters

Source/Engine/Tools/MaterialGenerator/MaterialGenerator.cpp

@@ -186,6 +186,8 @@ bool MaterialGenerator::Generate(WriteStream& source, MaterialInfo& materialInfo
         ADD_FEATURE(TessellationFeature);
         if (materialInfo.BlendMode == MaterialBlendMode::Opaque)
         ADD_FEATURE(LightmapFeature);
+        if (materialInfo.BlendMode != MaterialBlendMode::Opaque && (materialInfo.FeaturesFlags & MaterialFeaturesFlags::DisableDistortion) == 0)
+        ADD_FEATURE(DistortionFeature);
         break;
     case MaterialDomain::Terrain:
         if (materialInfo.TessellationMode != TessellationMethod::None)
@@ -193,6 +195,10 @@ bool MaterialGenerator::Generate(WriteStream& source, MaterialInfo& materialInfo
         ADD_FEATURE(LightmapFeature);
         break;
     default:
+    case MaterialDomain::Particle:
+        if (materialInfo.BlendMode != MaterialBlendMode::Opaque && (materialInfo.FeaturesFlags & MaterialFeaturesFlags::DisableDistortion) == 0)
+        ADD_FEATURE(DistortionFeature);
+        break;
         break;
     }
 #undef ADD_FEATURE