2 accidental-placement.cc -- implement Accidental_placement
4 source file of the GNU LilyPond music typesetter
6 (c) 2002--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>
11 #include "accidental-placement.hh"
12 #include "libc-extension.hh" // isinf
17 #include "note-column.hh"
18 #include "pointer-group-interface.hh"
19 #include "note-collision.hh"
20 #include "accidental-interface.hh"
22 MAKE_SCHEME_CALLBACK (Accidental_placement, alignment_callback, 2);
24 Accidental_placement::alignment_callback (SCM s, SCM)
26 Grob *me = unsmob_grob (s);
28 Grob *par = me->get_parent (X_AXIS);
29 if (!to_boolean (par->get_property ("positioning-done")))
31 par->set_property ("positioning-done", SCM_BOOL_T);
32 position_accidentals (par);
35 return scm_from_int (0);
39 Accidental_placement::add_accidental (Grob *me, Grob *a)
41 a->set_parent (me, X_AXIS);
42 a->add_offset_callback (alignment_callback_proc, X_AXIS);
43 SCM cause = a->get_parent (Y_AXIS)->get_property ("cause");
45 Music *mcause = unsmob_music (cause);
48 programming_error ("note head has no music cause");
52 Pitch *p = unsmob_pitch (mcause->get_property ("pitch"));
54 int n = p->get_notename ();
56 SCM accs = me->get_object ("accidental-grobs");
57 SCM key = scm_from_int (n);
58 SCM entry = scm_assq (key, accs);
59 if (entry == SCM_BOOL_F)
62 entry = scm_cdr (entry);
64 entry = scm_cons (a->self_scm (), entry);
66 accs = scm_assq_set_x (accs, key, entry);
68 me->set_object ("accidental-grobs", accs);
72 Split into break reminders.
75 Accidental_placement::split_accidentals (Grob *accs,
76 Link_array<Grob> *break_reminder,
77 Link_array<Grob> *real_acc)
79 for (SCM acs = accs->get_object ("accidental-grobs"); scm_is_pair (acs);
81 for (SCM s = scm_cdar (acs); scm_is_pair (s); s = scm_cdr (s))
83 Grob *a = unsmob_grob (scm_car (s));
85 if (unsmob_grob (a->get_object ("tie")))
86 break_reminder->push (a);
93 Accidentals are special, because they appear and disappear after
97 Accidental_placement::get_relevant_accidental_extent (Grob *me,
101 Link_array<Grob> br, ra;
102 Link_array<Grob> *which = 0;
104 Accidental_placement::split_accidentals (me, &br, &ra);
107 if (dynamic_cast<Item *> (left_object)->break_status_dir () == RIGHT)
113 for (int i = 0; i < which->size (); i++)
114 extent.unite (which->elem (i)->extent (item_col, X_AXIS));
116 if (!extent.is_empty ())
118 Real p = robust_scm2double (me->get_property ("left-padding"), 0.2);
125 struct Accidental_placement_entry
127 Array<Skyline_entry> left_skyline_;
128 Array<Skyline_entry> right_skyline_;
129 Interval vertical_extent_;
131 Link_array<Grob> grobs_;
134 Accidental_placement_entry ()
141 static Interval all_accidental_vertical_extent;
142 Real ape_priority (Accidental_placement_entry const *a)
144 return a->vertical_extent_[UP];
147 int ape_compare (Accidental_placement_entry *const &a,
148 Accidental_placement_entry *const &b)
150 return sign (ape_priority (a) - ape_priority (b));
153 int ape_rcompare (Accidental_placement_entry *const &a,
154 Accidental_placement_entry *const &b)
156 return -sign (ape_priority (a) - ape_priority (b));
168 stagger_apes (Link_array<Accidental_placement_entry> *apes)
170 Link_array<Accidental_placement_entry> asc = *apes;
172 asc.sort (&ape_compare);
178 while (i < asc.size ())
180 Accidental_placement_entry *a = 0;
194 This routine computes placements of accidentals. During
195 add_accidental (), accidentals are already grouped by note, so that
196 octaves are placed above each other; they form columns. Then the
197 columns are sorted: the biggest columns go closest to the note.
198 Then the columns are spaced as closely as possible (using skyline
202 TODO: more advanced placement. Typically, the accs should be placed
203 to form a C shape, like this
212 The naturals should be left of the C as well; they should
215 Note that this placement problem looks NP hard, so we just use a
216 simple strategy, not an optimal choice.
220 TODO: there should be more space in the following situation
231 Accidental_placement::position_accidentals (Grob *me)
234 return SCM_UNSPECIFIED;
236 SCM accs = me->get_object ("accidental-grobs");
237 if (!scm_is_pair (accs))
238 return SCM_UNSPECIFIED;
241 TODO: there is a bug in this code. If two accs are on the same
242 Y-position, they share an Ape, and will be printed in overstrike.
244 Link_array<Accidental_placement_entry> apes;
245 for (SCM s = accs; scm_is_pair (s); s = scm_cdr (s))
247 Accidental_placement_entry *ape = new Accidental_placement_entry;
248 ape->notename_ = scm_to_int (scm_caar (s));
250 for (SCM t = scm_cdar (s); scm_is_pair (t); t = scm_cdr (t))
251 ape->grobs_.push (unsmob_grob (scm_car (t)));
256 Grob *common[] = {me, 0};
259 First we must extract *all* pointers. We can only determine
260 extents if we're sure that we've found the right common refpoint
262 Link_array<Grob> note_cols, heads;
263 for (int i = apes.size (); i--;)
265 Accidental_placement_entry *ape = apes[i];
266 for (int j = ape->grobs_.size (); j--;)
268 Grob *a = ape->grobs_[j];
271 common[Y_AXIS] = common[Y_AXIS]->common_refpoint (a, Y_AXIS);
275 Grob *head = a->get_parent (Y_AXIS);
277 Grob *col = head->get_parent (X_AXIS);
278 if (Note_column::has_interface (col))
279 note_cols.push (col);
286 This is a little kludgy: to get all notes, we look if there are
289 for (int i = note_cols.size (); i--;)
291 Grob *c = note_cols[i]->get_parent (X_AXIS);
292 if (Note_collision_interface::has_interface (c))
294 extract_grob_set (c, "elements", gs);
296 note_cols.concat (gs);
300 for (int i = note_cols.size (); i--;)
301 heads.concat (extract_grob_array (note_cols[i], "note-heads"));
303 heads.default_sort ();
305 common[Y_AXIS] = common_refpoint_of_array (heads, common[Y_AXIS], Y_AXIS);
307 for (int i = apes.size (); i--;)
309 Accidental_placement_entry *ape = apes[i];
310 ape->left_skyline_ = empty_skyline (LEFT);
311 ape->right_skyline_ = empty_skyline (RIGHT);
313 for (int j = apes[i]->grobs_.size (); j--;)
315 Grob *a = apes[i]->grobs_[j];
317 Array<Box> boxes = Accidental_interface::accurate_boxes (a, common);
319 ape->extents_.concat (boxes);
320 for (int j = boxes.size (); j--;)
322 insert_extent_into_skyline (&ape->left_skyline_, boxes[j], Y_AXIS, LEFT);
323 insert_extent_into_skyline (&ape->right_skyline_, boxes[j], Y_AXIS, RIGHT);
329 for (int i = apes.size (); i--;)
333 for (int j = apes[i]->extents_.size (); j--;)
334 y.unite (apes[i]->extents_[j][Y_AXIS]);
335 apes[i]->vertical_extent_ = y;
338 all_accidental_vertical_extent = total;
339 stagger_apes (&apes);
341 Accidental_placement_entry *head_ape = new Accidental_placement_entry;
342 common[X_AXIS] = common_refpoint_of_array (heads, common[X_AXIS], X_AXIS);
343 Array<Skyline_entry> head_skyline (empty_skyline (LEFT));
344 Array<Box> head_extents;
345 for (int i = heads.size (); i--;)
347 Box b (heads[i]->extent (common[X_AXIS], X_AXIS),
348 heads[i]->extent (common[Y_AXIS], Y_AXIS));
350 insert_extent_into_skyline (&head_skyline, b, Y_AXIS, LEFT);
353 head_ape->left_skyline_ = head_skyline;
354 head_ape->offset_ = 0.0;
356 Real padding = robust_scm2double (me->get_property ("padding"), 0.2);
358 Array<Skyline_entry> left_skyline = head_ape->left_skyline_;
359 heighten_skyline (&left_skyline,
360 -robust_scm2double (me->get_property ("right-padding"), 0));
362 Add accs entries right-to-left.
364 for (int i = apes.size (); i-- > 0;)
367 = -skyline_meshing_distance (apes[i]->right_skyline_, left_skyline);
369 offset = (i < apes.size () - 1) ? apes[i + 1]->offset_ : 0.0;
373 apes[i]->offset_ = offset;
375 Array<Skyline_entry> new_left_skyline = apes[i]->left_skyline_;
376 heighten_skyline (&new_left_skyline, apes[i]->offset_);
377 merge_skyline (&new_left_skyline, left_skyline, LEFT);
378 left_skyline = new_left_skyline;
381 for (int i = apes.size (); i--;)
383 Accidental_placement_entry *ape = apes[i];
384 for (int j = ape->grobs_.size (); j--;)
385 ape->grobs_[j]->translate_axis (ape->offset_, X_AXIS);
388 Interval left_extent, right_extent;
389 Accidental_placement_entry *ape = apes[0];
391 for (int i = ape->extents_.size (); i--;)
392 left_extent.unite (ape->offset_ + ape->extents_[i][X_AXIS]);
395 for (int i = ape->extents_.size (); i--;)
396 right_extent.unite (ape->offset_ + ape->extents_[i][X_AXIS]);
398 left_extent[LEFT] -= robust_scm2double (me->get_property ("left-padding"), 0);
399 Interval width (left_extent[LEFT], right_extent[RIGHT]);
401 SCM scm_width = ly_interval2scm (width);
402 me->set_extent (scm_width, X_AXIS);
404 for (int i = apes.size (); i--;)
407 return SCM_UNSPECIFIED;
410 ADD_INTERFACE (Accidental_placement,
411 "accidental-placement-interface",
412 "Resolve accidental collisions.",
413 "left-padding padding right-padding accidental-grobs positioning-done")