lily/accidental-placement.cc

   1 /*
   2 accidental-placement.cc --  implement Accidental_placement
   3
   4 source file of the GNU LilyPond music typesetter
   5
   6 (c) 2002--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include <math.h>
  11 #include <libc-extension.hh>
  12
  13 #include "item.hh"
  14 #include "skyline.hh"
  15 #include "music.hh"
  16 #include "pitch.hh"
  17 #include "warn.hh"
  18 #include "accidental-placement.hh"
  19 #include "note-column.hh"
  20 #include "group-interface.hh"
  21 #include "note-collision.hh"
  22 #include "accidental-interface.hh"
  23
  24 MAKE_SCHEME_CALLBACK (Accidental_placement,alignment_callback, 2);
  25 SCM
  26 Accidental_placement::alignment_callback (SCM s, SCM )
  27 {
  28   Grob * me =unsmob_grob (s);
  29
  30   Grob * par = me->get_parent (X_AXIS);
  31   if (!to_boolean (par->get_property ("positioning-done")))
  32     {
  33       par->set_property ("positioning-done", SCM_BOOL_T);
  34       position_accidentals (par);
  35     }
  36
  37   return scm_int2num (0);
  38 }
  39
  40
  41 void
  42 Accidental_placement::add_accidental (Grob* me, Grob* a)
  43 {
  44   a->set_parent (me, X_AXIS);
  45   a->add_offset_callback (alignment_callback_proc, X_AXIS);
  46   SCM cause = a->get_parent (Y_AXIS)->get_property ("cause");
  47
  48   Music *mcause =unsmob_music (cause);
  49   if (!mcause)
  50     {
  51       programming_error ("Note head has no music cause!");
  52       return;
  53     }
  54
  55   Pitch *p= unsmob_pitch (mcause->get_property ("pitch"));
  56
  57   int n = p->get_notename ();
  58
  59   SCM accs = me->get_property ("accidental-grobs");
  60   SCM key = scm_int2num (n);
  61   SCM entry = scm_assq (key, accs);
  62   if (entry == SCM_BOOL_F)
  63     {
  64       entry = SCM_EOL;
  65     }
  66   else
  67     entry = gh_cdr (entry);
  68
  69   entry = gh_cons (a->self_scm (), entry);
  70
  71   accs = scm_assq_set_x (accs,  key, entry);
  72
  73   me->set_property ("accidental-grobs", accs);
  74 }
  75
  76 /*
  77   Split into break reminders.
  78  */
  79 void
  80 Accidental_placement::split_accidentals (Grob * accs,
  81                                          Link_array<Grob> *break_reminder,
  82                                          Link_array<Grob> *real_acc)
  83 {
  84   for (SCM acs =accs->get_property ("accidental-grobs"); gh_pair_p (acs);
  85        acs =gh_cdr (acs))
  86     for (SCM s = gh_cdar (acs); gh_pair_p (s); s = gh_cdr (s))
  87       {
  88         Grob *a = unsmob_grob (gh_car (s));
  89
  90         if (unsmob_grob (a->get_property ("tie")))
  91           break_reminder->push (a);
  92         else
  93           real_acc->push (a);
  94       }
  95 }
  96
  97 /*
  98   Accidentals are special, because they appear and disappear after
  99   ties at will.
 100 */
 101 Interval
 102 Accidental_placement::get_relevant_accidental_extent (Grob *me,
 103                                                       Item *item_col,
 104                                                       Grob *left_object)
 105 {
 106   Link_array<Grob> br, ra;
 107   Link_array<Grob> *which = 0;
 108
 109   Accidental_placement::split_accidentals (me, &br, &ra);
 110   br.concat (ra);
 111
 112   if (dynamic_cast<Item*>(left_object)->break_status_dir () == RIGHT)
 113     which = & br;
 114   else
 115     which = & ra;
 116
 117   Interval extent;
 118   for (int i = 0; i < which->size (); i++)
 119     {
 120       extent.unite (which->elem (i)->extent (item_col, X_AXIS));
 121     }
 122
 123   if (!extent.is_empty ())
 124     {
 125       Real p = robust_scm2double (me->get_property ("left-padding"), 0.2);
 126       extent[LEFT] -= p;
 127     }
 128
 129   return extent;
 130 }
 131
 132
 133
 134 struct Accidental_placement_entry
 135 {
 136   Array<Skyline_entry> left_skyline_;
 137   Array<Skyline_entry> right_skyline_;
 138   Interval vertical_extent_;
 139   Array<Box> extents_;
 140   Link_array<Grob> grobs_;
 141   Real offset_;
 142   int notename_;
 143   Accidental_placement_entry ()
 144   {
 145     offset_ =0.0;
 146     notename_ = -1;
 147   }
 148 };
 149
 150 static Interval all_accidental_vertical_extent;
 151 Real ape_priority (Accidental_placement_entry const * a)
 152 {
 153   return a->vertical_extent_[UP];
 154 }
 155
 156
 157
 158 int ape_compare (Accidental_placement_entry *const &a,
 159                  Accidental_placement_entry *const &b)
 160 {
 161   return sign (ape_priority (a) - ape_priority (b));
 162 }
 163
 164 int ape_rcompare (Accidental_placement_entry *const &a,
 165                  Accidental_placement_entry *const &b)
 166 {
 167   return -sign (ape_priority (a) - ape_priority (b));
 168 }
 169
 170
 171 /*
 172
 173 TODO: should favor
 174
 175   b
 176  b
 177
 178 placement
 179
 180 */
 181 void
 182 stagger_apes (Link_array<Accidental_placement_entry> *apes)
 183 {
 184   Link_array<Accidental_placement_entry> asc = *apes;
 185
 186
 187   asc.sort (&ape_compare);
 188
 189   apes->clear ();
 190
 191   int i =0;
 192   int parity = 1;
 193   while (i < asc.size ())
 194     {
 195       Accidental_placement_entry * a = 0;
 196       if (parity)
 197         a = asc.pop ();
 198       else
 199         a = asc[i++];
 200
 201       apes->push (a);
 202       parity = !parity;
 203     }
 204
 205   apes->reverse ();
 206 }
 207
 208
 209
 210 /*
 211
 212   This routine computes placements of accidentals. During
 213   add_accidental (), accidentals are already grouped by note, so that
 214   octaves are placed above each other; they form columns. Then the
 215   columns are sorted: the biggest columns go closest to the note.
 216   Then the columns are spaced as closely as possible (using skyline
 217   spacing).
 218
 219
 220   TODO: more advanced placement. Typically, the accs should be placed
 221   to form a C shape, like this
 222
 223
 224            ##
 225         b b
 226        # #
 227         b
 228           b b
 229
 230    The naturals should be left of the C as well; they should
 231    be separate accs.
 232
 233    Note that this placement problem looks NP hard, so we just use a
 234    simple strategy, not an optimal choice.
 235
 236 */
 237
 238 /*
 239   TODO: there should be more space in the following situation
 240
 241
 242     Natural + downstem
 243
 244     |_
 245     | |    X
 246     |_|   |
 247       |   |
 248
 249  */
 250 SCM
 251 Accidental_placement::position_accidentals (Grob * me)
 252 {
 253   if (!me->live ())
 254     return SCM_UNSPECIFIED;
 255
 256   SCM accs = me->get_property ("accidental-grobs");
 257
 258   /*
 259     TODO: there is a bug in this code. If two accs are on the same
 260     Y-position, they share an Ape, and will be printed in overstrike.
 261    */
 262   Link_array<Accidental_placement_entry> apes;
 263   for (SCM s = accs; gh_pair_p (s); s =gh_cdr (s))
 264     {
 265       Accidental_placement_entry *ape = new Accidental_placement_entry;
 266       ape->notename_ = gh_scm2int (gh_caar (s));
 267
 268       for (SCM t = gh_cdar (s); gh_pair_p (t); t =gh_cdr (t))
 269         ape->grobs_.push (unsmob_grob (gh_car (t)));
 270
 271       apes.push (ape);
 272     }
 273
 274
 275   Grob *common[] = {me, 0};
 276
 277   /*
 278     First we must extract *all* pointers. We can only determine
 279     extents if we're sure that we've found the right common refpoint
 280    */
 281   Link_array<Grob> note_cols, heads;
 282   for (int i= apes.size (); i--;)
 283     {
 284       Accidental_placement_entry * ape = apes[i];
 285       for (int j = ape->grobs_.size (); j--;)
 286         {
 287           Grob * a = ape->grobs_[j];
 288
 289           if (common[Y_AXIS])
 290             common[Y_AXIS] = common[Y_AXIS]->common_refpoint (a, Y_AXIS);
 291           else
 292             common[Y_AXIS] = a;
 293
 294           Grob *head = a->get_parent (Y_AXIS);
 295
 296           Grob * col = head->get_parent (X_AXIS);
 297           if (Note_column::has_interface (col))
 298             note_cols.push (col);
 299           else
 300             heads.push (head);
 301         }
 302     }
 303
 304   /*
 305     This is a little kludgy: to get all notes, we look if there are
 306     collisions as well.
 307    */
 308   for (int i = note_cols.size () ; i--;)
 309     {
 310       Grob *c = note_cols[i]->get_parent (X_AXIS);
 311       if (Note_collision_interface::has_interface (c))
 312         {
 313           Link_array<Grob> gs =
 314             Pointer_group_interface__extract_grobs (c, (Grob*)0, "elements");
 315
 316           note_cols.concat (gs);
 317         }
 318     }
 319
 320   for (int i = note_cols.size () ; i--;)
 321     {
 322       heads.concat (Pointer_group_interface__extract_grobs (note_cols[i],
 323                                                             (Grob*)0,
 324                                                             "note-heads"));
 325
 326     }
 327   heads.default_sort ();
 328   heads.uniq ();
 329   common[Y_AXIS] = common_refpoint_of_array (heads, common[Y_AXIS], Y_AXIS);
 330
 331
 332   for (int i= apes.size (); i--;)
 333     {
 334       Accidental_placement_entry * ape = apes[i];
 335       ape->left_skyline_ = empty_skyline (LEFT);
 336       ape->right_skyline_ = empty_skyline (RIGHT);
 337
 338       for (int j = apes[i]->grobs_.size (); j--;)
 339         {
 340           Grob * a = apes[i]->grobs_[j];
 341
 342           Array<Box> boxes = Accidental_interface::accurate_boxes (a, common);
 343
 344           ape->extents_.concat (boxes);
 345           for (int j  = boxes.size (); j--;)
 346             {
 347               insert_extent_into_skyline (&ape->left_skyline_, boxes[j], Y_AXIS, LEFT);
 348               insert_extent_into_skyline (&ape->right_skyline_ , boxes[j], Y_AXIS, RIGHT);
 349             }
 350         }
 351     }
 352
 353
 354   Interval total;
 355   for (int i = apes.size (); i--;)
 356     {
 357       Interval y ;
 358
 359       for (int j = apes[i]->extents_.size (); j--;)
 360         {
 361           y.unite (apes[i]->extents_[j][Y_AXIS]);
 362         }
 363       apes[i]->vertical_extent_ = y;
 364       total.unite (y);
 365     }
 366   all_accidental_vertical_extent = total;
 367   stagger_apes (&apes);
 368
 369   Accidental_placement_entry * head_ape = new Accidental_placement_entry;
 370   common[X_AXIS] = common_refpoint_of_array (heads, common[X_AXIS], X_AXIS);
 371   Array<Skyline_entry> head_skyline (empty_skyline (LEFT));
 372   Array<Box> head_extents;
 373   for (int i = heads.size (); i--;)
 374     {
 375       Box b (heads[i]->extent (common[X_AXIS] , X_AXIS),
 376             heads[i]->extent (common[Y_AXIS], Y_AXIS));
 377
 378       insert_extent_into_skyline (&head_skyline, b , Y_AXIS, LEFT);
 379     }
 380
 381   head_ape-> left_skyline_ = head_skyline;
 382   head_ape->offset_ = 0.0;
 383
 384   Real padding = robust_scm2double (me->get_property ("padding"),0.2);
 385
 386   Array<Skyline_entry> left_skyline = head_ape->left_skyline_;
 387   heighten_skyline (&left_skyline,
 388                     -robust_scm2double (me->get_property ("right-padding"), 0));
 389   /*
 390     Add accs entries right-to-left.
 391    */
 392   for (int i= apes.size (); i-- > 0;)
 393     {
 394       Real offset =
 395         -skyline_meshing_distance (apes[i]->right_skyline_, left_skyline);
 396       if (isinf (offset))
 397         offset = (i < apes.size () - 1) ? apes[i+1]->offset_ : 0.0;
 398       else
 399         offset -= padding;
 400
 401       apes[i]->offset_ = offset;
 402
 403       Array<Skyline_entry> new_left_skyline = apes[i]->left_skyline_;
 404       heighten_skyline (&new_left_skyline, apes[i]->offset_);
 405       merge_skyline (&new_left_skyline, left_skyline, LEFT);
 406       left_skyline = new_left_skyline;
 407     }
 408
 409   for (int i = apes.size (); i--;)
 410     {
 411       Accidental_placement_entry* ape = apes[i];
 412       for (int j  = ape->grobs_.size (); j--;)
 413         {
 414           ape->grobs_[j]->translate_axis (ape->offset_, X_AXIS);
 415         }
 416     }
 417
 418
 419   Interval left_extent, right_extent;
 420   Accidental_placement_entry *ape = apes[0];
 421
 422   for (int i = ape->extents_.size (); i--;)
 423     left_extent.unite (ape->offset_ +  ape->extents_[i][X_AXIS]);
 424
 425   ape = apes.top ();
 426   for (int i = ape->extents_.size (); i--;)
 427     right_extent.unite (ape->offset_  + ape->extents_[i][X_AXIS]);
 428
 429
 430   left_extent[LEFT] -= robust_scm2double (me->get_property ("left-padding"), 0);
 431
 432
 433   Interval width (left_extent[LEFT], right_extent[RIGHT]);
 434
 435   SCM scm_width = ly_interval2scm (width);
 436   me->set_extent (scm_width, X_AXIS);
 437
 438   for (int i = apes.size (); i--;)
 439     delete apes[i];
 440
 441   return SCM_UNSPECIFIED;
 442 }
 443
 444 ADD_INTERFACE (Accidental_placement,
 445               "accidental-placement-interface",
 446               "Resolve accidental collisions.",
 447               "left-padding padding right-padding accidental-grobs positioning-done")