Map/Unmap buffers via IGraphicscontext

Author: deccer

src/EngineKit/Extensions/ToGLExtensions.cs

@@ -44,11 +44,14 @@ public static int ToGL(this Swizzle swizzle)
         };
     }
 
-    public static GL.BufferStorageMask ToGL(this StorageAllocationFlags storageAllocationFlags)
+    public static uint ToGL(this StorageAllocationFlags storageAllocationFlags)
     {
-        GL.BufferStorageMask result = 0u;
-        result |= (storageAllocationFlags & StorageAllocationFlags.Dynamic) == StorageAllocationFlags.Dynamic ? GL.BufferStorageMask.DynamicStorageBit : 0;
-        result |= (storageAllocationFlags & StorageAllocationFlags.Client) == StorageAllocationFlags.Client ? GL.BufferStorageMask.ClientStorageBit : 0;
+        var result = 0u;
+        result |= (storageAllocationFlags & StorageAllocationFlags.Dynamic) == StorageAllocationFlags.Dynamic ? (uint)GL.BufferStorageFlags.DynamicStorageBit : 0;
+        result |= (storageAllocationFlags & StorageAllocationFlags.Client) == StorageAllocationFlags.Client ? (uint)GL.BufferStorageFlags.ClientStorageBit : 0;
+        result |= (storageAllocationFlags & StorageAllocationFlags.Mappable) == StorageAllocationFlags.Mappable
+            ? (uint)(GL.MapFlags.Persistent | GL.MapFlags.Coherent)
+            : 0;
         return result;
     }
 

src/EngineKit/Graphics/Buffer.cs

@@ -20,6 +20,8 @@ protected Buffer()
     public int Count { get; protected set; }
 
     public int SizeInBytes { get; private set; }
+    
+    public bool IsMappable { get; private set; }
 
     public void Dispose()
     {
@@ -31,6 +33,7 @@ public void AllocateStorage(int sizeInBytes, StorageAllocationFlags storageAlloc
         GL.NamedBufferStorage(Id, sizeInBytes, nint.Zero, storageAllocationFlags.ToGL());
         SizeInBytes = sizeInBytes;
         Count = SizeInBytes / Stride;
+        IsMappable = storageAllocationFlags.HasFlag(StorageAllocationFlags.Mappable);
     }
 
     public void AllocateStorage<TElement>(TElement element, StorageAllocationFlags storageAllocationFlags)
@@ -39,6 +42,7 @@ public void AllocateStorage<TElement>(TElement element, StorageAllocationFlags s
         GL.NamedBufferStorage(Id, element, storageAllocationFlags.ToGL());
         Count = 1;
         SizeInBytes = Marshal.SizeOf<TElement>();
+        IsMappable = storageAllocationFlags.HasFlag(StorageAllocationFlags.Mappable);
     }
 
     public void AllocateStorage<TElement>(TElement[] elements, StorageAllocationFlags storageAllocationFlags)
@@ -47,6 +51,7 @@ public void AllocateStorage<TElement>(TElement[] elements, StorageAllocationFlag
         GL.NamedBufferStorage(Id, elements, storageAllocationFlags.ToGL());
         Count = elements.Length;
         SizeInBytes = Marshal.SizeOf<TElement>() * Count;
+        IsMappable = storageAllocationFlags.HasFlag(StorageAllocationFlags.Mappable);
     }
 
     public unsafe void Update(nint dataPtr, int offsetInBytes, int sizeInBytes)

src/EngineKit/Graphics/GraphicsContext.cs

@@ -159,6 +159,23 @@ public Result<IGraphicsPipeline> CreateGraphicsPipeline(GraphicsPipelineDescript
         return Result.Success<IGraphicsPipeline>(graphicsPipeline);
     }
 
+    public unsafe bool TryMapBuffer(IBuffer buffer, MemoryAccess memoryAccess, out nint bufferPtr)
+    {
+        if (!buffer.IsMappable)
+        {
+            bufferPtr = IntPtr.Zero;
+            return false;
+        }
+
+        bufferPtr = (nint)GL.MapBuffer(buffer.Id, memoryAccess.ToGL());
+        return true;
+    }
+
+    public void UnmapBuffer(IBuffer buffer)
+    {
+        GL.UnmapBuffer(buffer.Id);
+    }
+
     public IIndexBuffer CreateIndexBuffer(Label label, MeshPrimitive[] meshPrimitives)
     {
         var indices = meshPrimitives

src/EngineKit/Graphics/IBuffer.cs

@@ -9,6 +9,8 @@ public interface IBuffer : IDisposable
     int Stride { get; }
 
     int Count { get; }
+    
+    bool IsMappable { get; }
 
     void AllocateStorage(int sizeInBytes, StorageAllocationFlags storageAllocationFlags);
 

src/EngineKit/Graphics/IGraphicsContext.cs

@@ -18,6 +18,10 @@ void BlitFramebufferToSwapchain(
         int targetWidth,
         int targetHeight);
 
+    bool TryMapBuffer(IBuffer buffer, MemoryAccess memoryAccess, out nint bufferPtr);
+
+    void UnmapBuffer(IBuffer buffer);
+
     IIndexBuffer CreateIndexBuffer<TIndex>(Label label)
         where TIndex : unmanaged;
 

src/EngineKit/Graphics/StorageAllocationFlags.cs

@@ -7,5 +7,6 @@ public enum StorageAllocationFlags
 {
     None = 0,
     Dynamic = 1,
-    Client = 2
+    Client = 2,
+    Mappable = 4
 }