+
+ do
+ {
+ for (vsize i = ordered_rests[d].size () -1; i-- > 0;)
+ {
+ Real last_y = ordered_rests[d][i + 1]->extent (common, Y_AXIS)[d];
+ Real y = ordered_rests[d][i]->extent (common, Y_AXIS)[-d];
+
+ Real diff = d * ((last_y - y) / staff_space);
+ if (diff > 0)
+ Note_column::translate_rests (ordered_rests[d][i], d * (int) ceil (diff) * 2);
+ }
+ }
+ while (flip (&d) != LEFT);
+ }
+ else
+ {
+ /*
+ Rests and notes.
+ */
+ if (rests.size () > 1)
+ warning (_ ("too many colliding rests"));
+ Grob *rcol = 0;
+ Direction dir = CENTER;
+
+ for (vsize i = rests.size (); !rcol && i--;)
+ if (Note_column::dir (rests[i]))
+ {
+ rcol = rests[i];
+ dir = Note_column::dir (rcol);
+ }
+
+ if (!rcol)
+ return SCM_BOOL_T;
+
+ Grob *rest = Note_column::get_rest (rcol);
+ Grob *common = common_refpoint_of_array (notes, rcol, Y_AXIS);
+
+ Interval restdim = rcol->extent (common, Y_AXIS);
+ if (restdim.is_empty ())
+ return SCM_BOOL_T;
+
+ Real staff_space = Staff_symbol_referencer::staff_space (rcol);
+ Real minimum_dist = robust_scm2double (me->get_property ("minimum-distance"), 1.0) * staff_space;
+
+ Interval notedim;
+ for (vsize i = 0; i < notes.size (); i++)
+ {
+ if (Note_column::dir (notes[i]) == -dir
+ // If the note has already happened (but it has a long duration, so there is a collision),
+ // don't look at the stem. If we do, the rest gets shifted down a lot and it looks bad.
+ || dynamic_cast<Item*> (notes[i])->get_column () != dynamic_cast<Item*> (rest)->get_column ())
+ {
+ /* try not to look at the stem, as looking at a beamed
+ note may trigger beam positioning prematurely.
+
+ This happens with dotted rests, which need Y
+ positioning to compute X-positioning.
+ */
+ Grob *head = Note_column::first_head (notes[i]);
+ if (head)
+ notedim.unite (head->extent (common, Y_AXIS));
+ else
+ programming_error ("Note_column without first_head()");
+ }
+ else
+ notedim.unite (notes[i]->extent (common, Y_AXIS));
+ }
+
+ Real y = dir * max (0.0,
+ -dir * restdim[-dir] + dir * notedim[dir] + minimum_dist);
+
+ int stafflines = Staff_symbol_referencer::line_count (me);
+ if (!stafflines)
+ {
+ programming_error ("no staff line count");
+ stafflines = 5;
+ }
+
+ // move discretely by half spaces.
+ int discrete_y = dir * int (ceil (y / (0.5 * dir * staff_space)));
+
+ // move by whole spaces inside the staff.
+ if (fabs (Staff_symbol_referencer::get_position (rest)
+ + discrete_y) < stafflines + 1)
+ {
+ discrete_y = dir * int (ceil (dir * discrete_y / 2.0) * 2.0);
+ }
+
+ Note_column::translate_rests (rcol, discrete_y);
+ }
+ return SCM_BOOL_T;