2 rest-collision.cc -- implement Rest_collision
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>
9 #include "rest-collision.hh"
11 #include <cmath> // ceil.
15 #include "note-column.hh"
17 #include "rhythmic-head.hh"
18 #include "output-def.hh"
20 #include "pointer-group-interface.hh"
21 #include "staff-symbol-referencer.hh"
22 #include "duration.hh"
23 #include "directional-element-interface.hh"
25 MAKE_SCHEME_CALLBACK (Rest_collision, force_shift_callback, 1);
27 Rest_collision::force_shift_callback (SCM smob)
29 Grob *them = unsmob_grob (smob);
30 if (Note_column::has_rests (them))
32 Grob *collision = unsmob_grob (them->get_object ("rest-collision"));
36 (void) collision->get_property ("positioning-done");
39 return scm_from_double (0.0);
42 MAKE_SCHEME_CALLBACK (Rest_collision, force_shift_callback_rest, 1);
44 Rest_collision::force_shift_callback_rest (SCM rest)
46 Grob *rest_grob = unsmob_grob (rest);
47 Grob *parent = rest_grob->get_parent (X_AXIS);
48 if (Note_column::has_interface (parent))
49 return force_shift_callback (parent->self_scm ());
51 return scm_from_double (0.0);
55 Rest_collision::add_column (Grob *me, Grob *p)
57 Pointer_group_interface::add_grob (me, ly_symbol2scm ("elements"), p);
60 only add callback for the rests, since we don't move anything
65 add_offset_callback (p, Rest_collision::force_shift_callback_proc, Y_AXIS);
66 p->set_object ("rest-collision", me->self_scm ());
68 Grob *rest = unsmob_grob (p->get_object ("rest"));
71 rest->set_property ("Y-offset" ,
72 Rest_collision::force_shift_callback_rest_proc);
77 TODO: look at horizontal-shift to determine ordering between rests
78 for more than two voices.
80 MAKE_SCHEME_CALLBACK(Rest_collision, calc_positioning_done, 1);
82 Rest_collision::calc_positioning_done (SCM smob)
84 Grob *me = unsmob_grob (smob);
85 extract_grob_set (me, "elements", elts);
87 Link_array<Grob> rests;
88 Link_array<Grob> notes;
90 for (int i = 0; i < elts.size (); i++)
93 if (unsmob_grob (e->get_object ("rest")))
96 Ignore rests under beam.
98 Grob *st = unsmob_grob (e->get_object ("stem"));
99 if (st && unsmob_grob (st->get_object ("beam")))
109 handle rest-rest and rest-note collisions
112 * decide not to print rest if too crowded?
116 no partners to collide with
118 if (rests.size () + notes.size () < 2)
119 return SCM_UNSPECIFIED;
121 Real staff_space = Staff_symbol_referencer::staff_space (me);
129 This is incomplete: in case of an uneven number of rests, the
130 center one should be centered on the staff.
132 Drul_array<Link_array<Grob> > ordered_rests;
133 for (int i = 0; i < rests.size (); i++)
135 Grob *r = Note_column::get_rest (rests[i]);
137 Direction d = get_grob_direction (r);
139 ordered_rests[d].push (rests[i]);
141 rests[d]->warning (_ ("can't resolve rest collision: rest direction not set"));
146 ordered_rests[d].sort (Note_column::shift_compare);
147 while (flip (&d) != LEFT)
152 if (ordered_rests[d].size () < 1)
154 if (ordered_rests[-d].size () > 1)
155 ordered_rests[-d][0]->warning (_ ("too many colliding rests"));
157 return SCM_UNSPECIFIED;
160 while (flip (&d) != LEFT);
162 Grob *common = common_refpoint_of_array (ordered_rests[DOWN], me, Y_AXIS);
163 common = common_refpoint_of_array (ordered_rests[UP], common, Y_AXIS);
166 = (ordered_rests[DOWN].top ()->extent (common, Y_AXIS)[UP]
167 - ordered_rests[UP].top ()->extent (common, Y_AXIS)[DOWN]) / staff_space;
171 int amount_down = (int) ceil (diff / 2);
173 Note_column::translate_rests (ordered_rests[DOWN].top (),
176 Note_column::translate_rests (ordered_rests[UP].top (),
177 2 * int (ceil (diff)));
182 for (int i = ordered_rests[d].size () -1; i-- > 0;)
184 Real last_y = ordered_rests[d][i + 1]->extent (common, Y_AXIS)[d];
185 Real y = ordered_rests[d][i]->extent (common, Y_AXIS)[-d];
187 Real diff = d * ((last_y - y) / staff_space);
189 Note_column::translate_rests (ordered_rests[d][i], d * (int) ceil (diff) * 2);
192 while (flip (&d) != LEFT);
199 if (rests.size () > 1)
200 warning (_ ("too many colliding rests"));
202 Direction dir = CENTER;
204 for (int i = rests.size (); !rcol && i--;)
205 if (Note_column::dir (rests[i]))
207 dir = Note_column::dir (rests[i]);
212 return SCM_UNSPECIFIED;
214 Grob *common = common_refpoint_of_array (notes, rcol, Y_AXIS);
216 Interval restdim = rcol->extent (common, Y_AXIS);
217 if (restdim.is_empty ())
218 return SCM_UNSPECIFIED;
220 Real staff_space = Staff_symbol_referencer::staff_space (rcol);
221 Real minimum_dist = robust_scm2double (me->get_property ("minimum-distance"), 1.0) * staff_space;
224 for (int i = 0; i < notes.size (); i++)
225 notedim.unite (notes[i]->extent (common, Y_AXIS));
228 = minimum_dist + dir * max (notedim[dir] - restdim[-dir], 0.0);
230 int stafflines = Staff_symbol_referencer::line_count (me);
233 programming_error ("no staff line count");
237 // move discretely by half spaces.
238 int discrete_dist = int (ceil (dist / (0.5 * staff_space)));
240 // move by whole spaces inside the staff.
241 if (discrete_dist < stafflines + 1)
242 discrete_dist = int (ceil (discrete_dist / 2.0) * 2.0);
244 Note_column::translate_rests (rcol, dir * discrete_dist);
246 return SCM_UNSPECIFIED;
249 ADD_INTERFACE (Rest_collision, "rest-collision-interface",
250 "Move around ordinary rests (not multi-measure-rests) to avoid "