internal extern static unsafe int ChoosePixelFormat(IntPtr hDc, ref PixelFormatDescriptor pPfd);
internal extern static unsafe int DescribePixelFormat(IntPtr hdc, int ipfd, int cjpfd, ref PixelFormatDescriptor ppfd);
internal extern static Boolean SetPixelFormat(IntPtr hdc, int ipfd, ref PixelFormatDescriptor ppfd);