// the interval between the note and the first ledger line, not
// the whole interval between the note and the staff.
Interval iv (min (0.0, lines[UP] - my_ext[DOWN] + 1),
// the interval between the note and the first ledger line, not
// the whole interval between the note and the staff.
Interval iv (min (0.0, lines[UP] - my_ext[DOWN] + 1),