1 files changed, 103 insertions, 0 deletions
diff --git a/src/Ryujinx.Graphics.OpenGL/Buffer.cs b/src/Ryujinx.Graphics.OpenGL/Buffer.cs
new file mode 100644
index 00000000..af7d191a
--- /dev/null
+++ b/src/Ryujinx.Graphics.OpenGL/Buffer.cs
@@ -0,0 +1,103 @@
+using OpenTK.Graphics.OpenGL;
+using Ryujinx.Graphics.GAL;
+using System;
+
+namespace Ryujinx.Graphics.OpenGL
+{
+    static class Buffer
+    {
+        public static void Clear(BufferHandle destination, int offset, int size, uint value)
+        {
+            GL.BindBuffer(BufferTarget.CopyWriteBuffer, destination.ToInt32());
+
+            unsafe
+            {
+                uint* valueArr = stackalloc uint[1];
+
+                valueArr[0] = value;
+
+                GL.ClearBufferSubData(
+                    BufferTarget.CopyWriteBuffer,
+                    PixelInternalFormat.Rgba8ui,
+                    (IntPtr)offset,
+                    (IntPtr)size,
+                    PixelFormat.RgbaInteger,
+                    PixelType.UnsignedByte,
+                    (IntPtr)valueArr);
+            }
+        }
+
+        public static BufferHandle Create()
+        {
+            return Handle.FromInt32<BufferHandle>(GL.GenBuffer());
+        }
+
+        public static BufferHandle Create(int size)
+        {
+            int handle = GL.GenBuffer();
+
+            GL.BindBuffer(BufferTarget.CopyWriteBuffer, handle);
+            GL.BufferData(BufferTarget.CopyWriteBuffer, size, IntPtr.Zero, BufferUsageHint.DynamicDraw);
+
+            return Handle.FromInt32<BufferHandle>(handle);
+        }
+
+        public static void Copy(BufferHandle source, BufferHandle destination, int srcOffset, int dstOffset, int size)
+        {
+            GL.BindBuffer(BufferTarget.CopyReadBuffer, source.ToInt32());
+            GL.BindBuffer(BufferTarget.CopyWriteBuffer, destination.ToInt32());
+
+            GL.CopyBufferSubData(
+                BufferTarget.CopyReadBuffer,
+                BufferTarget.CopyWriteBuffer,
+                (IntPtr)srcOffset,
+                (IntPtr)dstOffset,
+                (IntPtr)size);
+        }
+
+        public static unsafe PinnedSpan<byte> GetData(OpenGLRenderer renderer, BufferHandle buffer, int offset, int size)
+        {
+            // Data in the persistent buffer and host array is guaranteed to be available
+            // until the next time the host thread requests data.
+
+            if (HwCapabilities.UsePersistentBufferForFlush)
+            {
+                return PinnedSpan<byte>.UnsafeFromSpan(renderer.PersistentBuffers.Default.GetBufferData(buffer, offset, size));
+            }
+            else
+            {
+                IntPtr target = renderer.PersistentBuffers.Default.GetHostArray(size);
+
+                GL.BindBuffer(BufferTarget.CopyReadBuffer, buffer.ToInt32());
+
+                GL.GetBufferSubData(BufferTarget.CopyReadBuffer, (IntPtr)offset, size, target);
+
+                return new PinnedSpan<byte>(target.ToPointer(), size);
+            }
+        }
+
+        public static void Resize(BufferHandle handle, int size)
+        {
+            GL.BindBuffer(BufferTarget.CopyWriteBuffer, handle.ToInt32());
+            GL.BufferData(BufferTarget.CopyWriteBuffer, size, IntPtr.Zero, BufferUsageHint.StreamCopy);
+        }
+
+        public static void SetData(BufferHandle buffer, int offset, ReadOnlySpan<byte> data)
+        {
+            GL.BindBuffer(BufferTarget.CopyWriteBuffer, buffer.ToInt32());
+
+            unsafe
+            {
+                fixed (byte* ptr = data)
+                {
+                    GL.BufferSubData(BufferTarget.CopyWriteBuffer, (IntPtr)offset, data.Length, (IntPtr)ptr);
+                }
+            }
+        }
+
+        public static void Delete(BufferHandle buffer)
+        {
+            GL.DeleteBuffer(buffer.ToInt32());
+        }
+    }
+}