Basic meshlet generation algorithm

src/Engine/Graphics/VertexData.h

@@ -15,6 +15,17 @@ namespace Component
 struct MeshId
 {
     uint64 id;
+    std::strong_ordering operator<=>(const MeshId& other) const
+    {
+        return id <=> other.id;
+    }
+};
+struct Meshlet
+{
+    uint32 uniqueVertices[Gfx::numVerticesPerMeshlet]; // unique vertiex indices in the vertex data
+    uint8 primitiveLayout[Gfx::numPrimitivesPerMeshlet * 3]; // indices into the uniqueVertices array, only uint8 needed
+    uint32 numVertices;
+    uint32 numPrimitives;
 };
 class VertexData
 {
@@ -44,9 +55,11 @@ public:
     {
         uint32 numMeshlets;
         uint32 meshletOffset;
+        uint32 vertexOffset;
     };
     void resetMeshData();
     void updateMesh(const Component::Transform& transform, const Component::Mesh& mesh);
+    void loadMesh(MeshId id, Array<Meshlet> meshlets);
     void createDescriptors();
     virtual MeshId allocateVertexData(uint64 numVertices) = 0;
     virtual void bindBuffers(Gfx::PRenderCommand command) = 0;
@@ -57,7 +70,10 @@ public:
     const Map<std::string, MaterialData>& getMaterialData() const { return materialData; }
     const Array<MeshData>& getMeshData(MeshId id) { return meshData[id]; }
     static List<VertexData*> getList();
+    virtual void init(Gfx::PGraphics graphics);
 protected:
+    virtual void updateBuffers() = 0;
+    VertexData();
     struct MeshletAABB
     {
         Vector min;
@@ -65,24 +81,26 @@ protected:
         Vector max;
         float pad1;
     };
-    struct MeshletData
+    struct MeshletDescription
     {
         MeshletAABB boundingBox;
         uint32_t vertexCount;
-        uint32_t primiticeCount;
+        uint32_t primitiveCount;
         uint32_t vertexOffset;
         uint32_t primitiveOffset;
     };
     Map<std::string, MaterialData> materialData;
     Map<MeshId, Array<MeshData>> meshData;
-    Array<MeshletData> meshlets;
-    Gfx::PDescriptorLayout instanceDataLayout;
+    Array<MeshletDescription> meshlets;
+    Array<uint8> primitiveIndices;
+    Array<uint32> vertexIndices;
     Gfx::PGraphics graphics;
+    Gfx::PDescriptorLayout instanceDataLayout;
     // for mesh shading
     Gfx::PShaderBuffer meshletBuffer;
     // for legacy pipeline
     Gfx::PIndexBuffer indexBuffer;
-    VertexData(Gfx::PGraphics graphics);
     uint64 idCounter;
+    bool dirty;
 };
 }