func GetMultisamplefv(pname uint32, index uint32, val *float32) {
	syscall.Syscall(gpGetMultisamplefv, 3, uintptr(pname), uintptr(index), uintptr(unsafe.Pointer(val)))
}
func GetMultisamplefv(pname uint32, index uint32, val *float32) {
	syscall.Syscall(gpGetMultisamplefv, 3, uintptr(pname), uintptr(index), uintptr(unsafe.Pointer(val)))
}
// retrieve the location of a sample