Add GPUVertexLayout to graphics backends

Source/Engine/Graphics/Shaders/VertexElement.h

@@ -0,0 +1,86 @@
+// Copyright (c) 2012-2024 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#include "Engine/Graphics/PixelFormat.h"
+
+/// <summary>
+/// Vertex buffer data element. Defines access to data passed to Vertex Shader.
+/// </summary>
+API_STRUCT(NoDefault)
+PACK_BEGIN() struct FLAXENGINE_API VertexElement
+{
+    DECLARE_SCRIPTING_TYPE_MINIMAL(VertexElement);
+
+    /// <summary>
+    /// Types of vertex elements.
+    /// </summary>
+    API_ENUM() enum class Types : byte
+    {
+        // Undefined.
+        Unknown = 0,
+        // Vertex position.
+        Position = 1,
+        // Vertex color.
+        Color = 2,
+        // Vertex normal vector.
+        Normal = 3,
+        // Vertex tangent vector.
+        Tangent = 4,
+        // Skinned bone blend indices.
+        BlendIndices = 5,
+        // Skinned bone blend weights.
+        BlendWeight = 6,
+        // Primary texture coordinate (UV).
+        TexCoord0 = 7,
+        // Additional texture coordinate (UV1).
+        TexCoord1 = 8,
+        // Additional texture coordinate (UV2).
+        TexCoord2 = 9,
+        // Additional texture coordinate (UV3).
+        TexCoord3 = 10,
+        // Additional texture coordinate (UV4).
+        TexCoord4 = 11,
+        // Additional texture coordinate (UV5).
+        TexCoord5 = 12,
+        // Additional texture coordinate (UV6).
+        TexCoord6 = 13,
+        // Additional texture coordinate (UV7).
+        TexCoord7 = 14,
+        // General purpose attribute (at index 0).
+        Attribute0 = 15,
+        // General purpose attribute (at index 1).
+        Attribute1 = 16,
+        // General purpose attribute (at index 2).
+        Attribute2 = 17,
+        // General purpose attribute (at index 3).
+        Attribute3 = 18,
+        // Texture coordinate.
+        TexCoord = TexCoord0,
+        // General purpose attribute.
+        Attribute = Attribute0,
+        MAX
+    };
+
+    // Type of the vertex element data.
+    Types Type;
+    // Index of the input vertex buffer slot (as provided in GPUContext::BindVB).
+    byte Slot;
+    // Byte offset of this element relative to the start of a vertex buffer. Use value 0 to use auto-calculated offset based on previous elements in the layout (or for the first one).
+    byte Offset;
+    // Flag used to mark data using hardware-instancing (element will be repeated for every instance). Empty to step data per-vertex when reading input buffer stream (rather than per-instance step).
+    byte PerInstance;
+    // Format of the vertex element data.
+    PixelFormat Format;
+
+    String ToString() const;
+
+    bool operator==(const VertexElement& other) const;
+
+    FORCE_INLINE bool operator!=(const VertexElement& other) const
+    {
+        return !operator==(other);
+    }
+} PACK_END();
+
+uint32 FLAXENGINE_API GetHash(const VertexElement& key);