double get_feather(int64_t position, int i, int direction);
double get_fader(int64_t position, int i, int direction);
int total_submasks(int64_t position, int direction);
double get_feather(int64_t position, int i, int direction);
double get_fader(int64_t position, int i, int direction);
int total_submasks(int64_t position, int direction);