1 files changed, 90 insertions, 0 deletions
diff --git a/Runtime/Graphics/GpuDataBuffer.h b/Runtime/Graphics/GpuDataBuffer.h
new file mode 100644
index 0000000..0d65d3d
--- /dev/null
+++ b/Runtime/Graphics/GpuDataBuffer.h
@@ -0,0 +1,90 @@
+#ifndef GPU_DATABUFFER_H
+#define GPU_DATABUFFER_H
+
+#include <vector>
+
+#include "../Utilities/Type.h"
+#include "../Utilities/Singleton.h"
+#include "../Utilities/UtilMacros.h"
+#include "../Utilities/Assert.h"
+#include "OpenGL.h"
+
+namespace GPU
+{
+
+	class DataBuffer 
+	{
+	public:
+		void Upload(int offset, int size, const void* data);
+		void* Map(uint32 access);
+		void* MapRange(int offset, int size, uint32 access); // best performance
+		void FlushMapedRange(int offset, int size);
+
+		void UnMap();
+
+		void Orphan();
+		
+		// claim storage of size
+		void Restore(int size, GLenum usage);
+		// claim storage of size and fill it
+		void RestoreWithData(int size, GLenum usage, const void* data);
+
+		GET(int, Size, m_Size);
+		GET(GLenum, Usage, m_Usage);
+		GET(GLuint, Handle, m_Handle);
+
+	private:
+		friend class BufferPool;
+		
+		DataBuffer();
+		~DataBuffer();
+
+		GLuint m_Handle;
+		int    m_Size;
+		GLenum m_Usage;
+	};
+
+	// recycle data buffer 
+	class BufferPool : public Singleton<BufferPool>
+	{
+	public: 
+		BufferPool();
+		~BufferPool();
+
+		void Initialize();
+	
+		DataBuffer* ClaimBuffer(int size, GLenum usage);
+		void ReleaseBuffer(DataBuffer* buffer);
+
+		void OnEndFrame();
+	
+	private: 
+
+		inline int GetSizeClassLimit(int classNdx);
+
+		void UpdatePendingBuffersArray();
+		void InsertToLive(DataBuffer* buffer);
+		uint GetSizeClass(uint bufferSize);
+
+		enum {
+			kSizeClassBaseLog2 = 10,
+			kSizeClassStepLog2 = 1,
+			kSizeClassCount = 7
+		};
+
+		std::vector<DataBuffer*>	m_LiveBuffers[kSizeClassCount];
+
+	};
+
+	inline int BufferPool::GetSizeClassLimit(int classNdx)
+	{
+		// (0, 2^10]    2^11    2^12    2^13    2^14    2^15    INT_MAX  
+		return classNdx + 1 < kSizeClassCount ? (1 << (classNdx*kSizeClassStepLog2 + kSizeClassBaseLog2)) : INT_MAX;
+	}
+
+	DataBuffer* ClaimBuffer(int size = 0, GLenum usage = GL_ARRAY_BUFFER);
+	void ReleaseBuffer(DataBuffer* buffer);
+
+}
+
+#endif
+\ No newline at end of file