func GetTexImage(target uint32, level int32, format uint32, xtype uint32, pixels unsafe.Pointer) {
	syscall.Syscall6(gpGetTexImage, 5, uintptr(target), uintptr(level), uintptr(format), uintptr(xtype), uintptr(pixels), 0)
}
func GetTexImage(target uint32, level int32, format uint32, xtype uint32, pixels unsafe.Pointer) {
	syscall.Syscall6(gpGetTexImage, 5, uintptr(target), uintptr(level), uintptr(format), uintptr(xtype), uintptr(pixels), 0)
}
// return a texture image