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Source/Engine/Tools/MaterialGenerator/MaterialLayer.h

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#if COMPILE_WITH_MATERIAL_GRAPH
+
+#include "Types.h"
+#include "Engine/Graphics/Materials/MaterialInfo.h"
+
+/// <summary>
+/// We use them to map layer's params ID.
+/// Used in layered materials to change param ID for each layer (two or more layers may have the same params ID from the same base material)
+/// </summary>
+struct LayerParamMapping
+{
+    Guid SrcId;
+    Guid DstId;
+};
+
+/// <summary>
+/// Single material layer
+/// </summary>
+class MaterialLayer
+{
+public:
+
+    struct LayerUsage
+    {
+        String VarName;
+        void* Hint;
+
+        LayerUsage()
+        {
+            Hint = nullptr;
+        }
+    };
+
+public:
+
+    /// <summary>
+    /// Layer ID
+    /// </summary>
+    Guid ID;
+
+    /// <summary>
+    /// Graph data
+    /// </summary>
+    MaterialGraph Graph;
+
+    /// <summary>
+    /// Root node
+    /// </summary>
+    MaterialGraphNode* Root;
+
+    /// <summary>
+    /// Material structure variable name (different for every layer sampling with different UVs, default UVs are a first index)
+    /// </summary>
+    LayerUsage Usage[4];
+
+    /// <summary>
+    /// Layer features flags
+    /// </summary>
+    MaterialFeaturesFlags FeaturesFlags;
+
+    /// <summary>
+    /// Layer usage flags
+    /// </summary>
+    MaterialUsageFlags UsageFlags;
+
+    /// <summary>
+    /// Domain
+    /// </summary>
+    MaterialDomain Domain;
+
+    /// <summary>
+    /// Blending mode
+    /// </summary>
+    MaterialBlendMode BlendMode;
+
+    /// <summary>
+    /// The shading model.
+    /// </summary>
+    MaterialShadingModel ShadingModel;
+
+    /// <summary>
+    /// The opacity threshold value (masked materials pixels clipping).
+    /// </summary>
+    float MaskThreshold;
+
+    /// <summary>
+    /// The opacity threshold value (transparent materials shadow pass though clipping).
+    /// </summary>
+    float OpacityThreshold;
+
+    /// <summary>
+    /// Helper array with original layer parameters Ids mappings into new Ids
+    /// Note: during sampling different materials layers we have to change their parameters Ids due to possible Ids collisions
+    /// Collisions may occur in duplicated materials so we want to resolve them.
+    /// </summary>
+    Array<LayerParamMapping> ParamIdsMappings;
+
+public:
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="MaterialLayer"/> class.
+    /// </summary>
+    /// <param name="id">The layer asset identifier.</param>
+    MaterialLayer(const Guid& id);
+
+public:
+
+    /// <summary>
+    /// Clear all cached values
+    /// </summary>
+    void ClearCache();
+
+    /// <summary>
+    /// Prepare layer for the material compilation process
+    /// </summary>
+    void Prepare();
+
+    Guid GetMappedParamId(const Guid& id);
+
+    String& GetVariableName(void* hint);
+
+    bool HasAnyVariableName();
+
+    void UpdateFeaturesFlags();
+
+public:
+
+    /// <summary>
+    /// Create default empty layer
+    /// </summary>
+    /// <param name="id">Layer id</param>
+    /// <returns>Layer</returns>
+    static MaterialLayer* CreateDefault(const Guid& id);
+
+    /// <summary>
+    /// Load layer data
+    /// </summary>
+    /// <param name="id">Layer id</param>
+    /// <param name="graphData">Stream with saved graph object</param>
+    /// <param name="info">Material info structure</param>
+    /// <param name="caller">Calling object name</param>
+    /// <returns>Layer</returns>
+    static MaterialLayer* Load(const Guid& id, ReadStream* graphData, const MaterialInfo& info, const String& caller);
+
+private:
+
+    void createRootNode();
+};
+
+#endif