- Grob *common = me->common_refpoint (staff, Y_AXIS);
-
- Interval staff_size = staff->maybe_pure_extent (common, Y_AXIS, pure, start, end);
- Real diff = dir*staff_size[dir] + padding - dir * (o + iv[-dir]);
- o += dir * max (diff, 0.0);
+ Grob *parent = me->get_parent (Y_AXIS);
+ Grob *common = me->common_refpoint (staff, Y_AXIS);
+ Real parent_position = parent->maybe_pure_coordinate (common, Y_AXIS, pure, start, end);
+ Real staff_position = staff->maybe_pure_coordinate (common, Y_AXIS, pure, start, end);
+ Interval staff_extent = staff->maybe_pure_extent (staff, a, pure, start, end);
+ Real diff = (dir * staff_extent[dir] + staff_padding
+ - dir * (o + iv[-dir])
+ + dir * (staff_position - parent_position));
+ o += dir * max (diff, 0.0);