func GetCompressedTexImage(target uint32, level int32, img unsafe.Pointer) {
	syscall.Syscall(gpGetCompressedTexImage, 3, uintptr(target), uintptr(level), uintptr(img))
}
func GetCompressedTexImage(target uint32, level int32, img unsafe.Pointer) {
	syscall.Syscall(gpGetCompressedTexImage, 3, uintptr(target), uintptr(level), uintptr(img))
}
// return a compressed texture image