typedef void (APIENTRY *PFNGLGENBUFFERSPROC) (GLsizei n, GLuint *buffers);
typedef void (APIENTRY *PFNGLBINDBUFFERPROC) (GLenum target, GLuint buffer);
typedef void (APIENTRY *PFNGLBUFFERDATAPROC) (GLenum target, ourGLsizeiptr size, const GLvoid *data, GLenum usage);
typedef void (APIENTRY *PFNGLGENBUFFERSPROC) (GLsizei n, GLuint *buffers);
typedef void (APIENTRY *PFNGLBINDBUFFERPROC) (GLenum target, GLuint buffer);
typedef void (APIENTRY *PFNGLBUFFERDATAPROC) (GLenum target, ourGLsizeiptr size, const GLvoid *data, GLenum usage);