lily/note-collision.cc

   1
   2 /*
   3   collision.cc -- implement Collision
   4
   5   source file of the GNU LilyPond music typesetter
   6
   7   (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   8 */
   9
  10 #include "warn.hh"
  11 #include "note-collision.hh"
  12 #include "note-column.hh"
  13 #include "note-head.hh"
  14 #include "rhythmic-head.hh"
  15 #include "paper-def.hh"
  16 #include "axis-group-interface.hh"
  17 #include "item.hh"
  18 #include "stem.hh"
  19
  20 MAKE_SCHEME_CALLBACK (Note_collision_interface,force_shift_callback,2);
  21
  22 SCM
  23 Note_collision_interface::force_shift_callback (SCM element_smob, SCM axis)
  24 {
  25   Grob *me = unsmob_grob (element_smob);
  26   Axis a = (Axis) gh_scm2int (axis);
  27   assert (a == X_AXIS);
  28
  29    me = me->get_parent (a);
  30
  31    if (! to_boolean (me->get_grob_property ("collision-done")))
  32     {
  33       me->set_grob_property ("collision-done", SCM_BOOL_T);
  34       do_shifts (me);
  35     }
  36
  37   return gh_double2scm (0.0);
  38 }
  39
  40
  41 void
  42 check_meshing_chords (Grob*me,
  43                       Drul_array< Array < Real > > *offsets,
  44                       Drul_array< Array < Slice > > const &extents,
  45                       Drul_array<Link_array<Grob> > const &clash_groups)
  46
  47 {
  48   if (!extents[UP].size () || ! extents[DOWN].size ())
  49     return ;
  50
  51
  52   Grob *cu =clash_groups[UP][0];
  53   Grob *cd =clash_groups[DOWN][0];
  54
  55   Grob * nu= Note_column::first_head (cu);
  56   Grob * nd = Note_column::first_head (cd);
  57
  58
  59
  60   /*
  61     this case (distant half collide),
  62
  63         |
  64       x |
  65      | x
  66      |
  67
  68    the noteheads may be closer than this case (close half collide)
  69
  70        |
  71        |
  72       x
  73      x
  74     |
  75     |
  76
  77    */
  78
  79   bool close_half_collide = false;
  80   bool distant_half_collide = false;
  81   bool full_collide = false;
  82
  83   /*
  84     Let's not crash.
  85    */
  86   if (!Note_column::get_stem (cu)
  87       || !Note_column::get_stem (cd))
  88     return ;
  89
  90
  91   /*
  92     TODO:
  93
  94     filter out the 'o's in this configuration, since they're no part
  95     in the collision.
  96
  97      |
  98     x|o
  99     x|o
 100     x
 101
 102
 103    */
 104   Array<int> ups = Stem::note_head_positions (Note_column::get_stem (cu));
 105   Array<int> dps = Stem::note_head_positions (Note_column::get_stem (cd));
 106
 107   /*
 108     they're too far apart to collide.
 109
 110    */
 111
 112   if (ups[0] > dps.top () + 1)
 113     return ;
 114
 115   bool touch = (ups[0] - dps.top () >= 0);
 116
 117   bool merge_possible = (ups[0] >= dps[0]) && (ups.top () >= dps.top ());
 118
 119   /*
 120     don't merge whole notes (or longer, like breve, longa, maxima)
 121    */
 122
 123   int upball_type = Note_head::get_balltype (nu);
 124   int dnball_type = Note_head::get_balltype (nd);
 125
 126   merge_possible = merge_possible && (upball_type > 0);
 127
 128   if (!to_boolean (me->get_grob_property ("merge-differently-dotted")))
 129     merge_possible = merge_possible && Rhythmic_head::dot_count (nu) == Rhythmic_head::dot_count (nd);
 130
 131
 132   if (!to_boolean (me->get_grob_property ("merge-differently-headed")))
 133     merge_possible = merge_possible &&
 134       upball_type == dnball_type;
 135   else
 136     /*
 137       Can't merge quarter and half notes.
 138      */
 139     merge_possible = merge_possible &&
 140       !((Rhythmic_head::duration_log (nu) == 1
 141          && Rhythmic_head::duration_log (nd) == 2)
 142         ||(Rhythmic_head::duration_log (nu) == 2
 143            && Rhythmic_head::duration_log (nd) == 1));
 144
 145   int i = 0, j=0;
 146   while (i < ups.size () && j < dps.size ())
 147   {
 148     if (abs (ups[i] - dps[j]) == 1)
 149       {
 150         merge_possible = false;
 151         if (ups[i] > dps[j])
 152           close_half_collide = true;
 153         else
 154           distant_half_collide = true;
 155       }
 156     else if (ups[i]==dps[j])
 157       full_collide = true;
 158     else if (ups[i] >dps[0] && ups[i] < dps.top ())
 159       merge_possible = false;
 160     else if (dps[j] >ups[0] && dps[j] < ups.top ())
 161       merge_possible = false;
 162
 163     if (ups[i] < dps[j])
 164       i++;
 165     else if (ups[i] > dps[j])
 166       j++;
 167     else
 168       {
 169         i++;
 170         j++;
 171       }
 172   }
 173
 174   Drul_array<Real> center_note_shifts;
 175   center_note_shifts[LEFT] = 0.0;
 176   center_note_shifts[RIGHT] = 0.0;
 177
 178
 179   Real shift_amount = 1;
 180
 181   if (touch)
 182     shift_amount *= -1;
 183
 184   /*
 185     for full collisions, the right hand head may obscure dots, so
 186     make sure the dotted heads go to the right.
 187    */
 188   if ((Rhythmic_head::dot_count (nu) > Rhythmic_head::dot_count (nd)
 189        && full_collide))
 190     shift_amount = 1;
 191
 192   /*
 193     TODO: these numbers are magic; should devise a set of grob props
 194     to tune this behavior.  */
 195
 196   if (merge_possible)
 197     {
 198       shift_amount *= 0.0;
 199       Grob *wipe_ball = 0;
 200
 201       if (upball_type  <  dnball_type)
 202         wipe_ball = nd;
 203       else if (upball_type > dnball_type)
 204         wipe_ball = nu;
 205
 206       if (wipe_ball && wipe_ball->live ())
 207         {
 208           wipe_ball->set_grob_property ("transparent", SCM_BOOL_T);
 209           wipe_ball->set_grob_property ("molecule", SCM_EOL);
 210         }
 211     }
 212   else if (close_half_collide && !touch)
 213     shift_amount *= 0.52;
 214   else if (distant_half_collide && !touch)
 215     shift_amount *= 0.4;
 216   else if (distant_half_collide || close_half_collide || full_collide)
 217     shift_amount *= 0.5;
 218
 219   /*
 220     we're meshing.
 221   */
 222   else if (Rhythmic_head::dot_count (nu) || Rhythmic_head::dot_count (nd))
 223     shift_amount *= 0.1;
 224   else
 225     shift_amount *= 0.25;
 226
 227   Direction d = UP;
 228   do
 229     {
 230       for (int i=0; i < clash_groups[d].size (); i++)
 231         (*offsets)[d][i] += d * shift_amount;
 232     }
 233   while ((flip (&d))!= UP);
 234 }
 235
 236 void
 237 Note_collision_interface::do_shifts (Grob* me)
 238 {
 239   Drul_array< Link_array <Grob>  > cg = get_clash_groups (me);
 240
 241   SCM autos (automatic_shift (me, cg));
 242   SCM hand (forced_shift (me));
 243
 244
 245
 246   Direction d = UP;
 247   Real wid = 0.0;
 248   do
 249     {
 250       if(cg[d].size())
 251         {
 252           Grob  *h = cg[d][0];
 253           wid = Note_column::first_head(h)->extent(h,X_AXIS).length() ;
 254         }
 255     }
 256
 257   while (flip (&d) != UP);
 258
 259
 260   Link_array<Grob> done;
 261   for (; gh_pair_p (hand); hand =ly_cdr (hand))
 262     {
 263       Grob * s = unsmob_grob (ly_caar (hand));
 264       Real amount = gh_scm2double (ly_cdar (hand));
 265
 266       s->translate_axis (amount *wid, X_AXIS);
 267       done.push (s);
 268     }
 269   for (; gh_pair_p (autos); autos =ly_cdr (autos))
 270     {
 271       Grob * s = unsmob_grob (ly_caar (autos));
 272       Real amount = gh_scm2double (ly_cdar (autos));
 273
 274       if (!done.find (s))
 275         s->translate_axis (amount * wid, X_AXIS);
 276     }
 277 }
 278
 279 Drul_array< Link_array <Grob>  >
 280 Note_collision_interface::get_clash_groups (Grob *me)
 281 {
 282   Drul_array<Link_array<Grob> > clash_groups;
 283
 284   SCM s = me->get_grob_property ("elements");
 285   for (; gh_pair_p (s); s = ly_cdr (s))
 286     {
 287       SCM car = ly_car (s);
 288
 289       Grob * se = unsmob_grob (car);
 290       if (Note_column::has_interface (se))
 291         clash_groups[Note_column::dir (se)].push (se);
 292     }
 293
 294   Direction d = UP;
 295   do
 296     {
 297       Link_array<Grob> & clashes (clash_groups[d]);
 298       clashes.sort (Note_column::shift_compare);
 299     }
 300   while ((flip (&d))!= UP);
 301
 302   return clash_groups;
 303 }
 304
 305 /** This complicated routine moves note columns around horizontally to
 306   ensure that notes don't clash.
 307
 308   This should be put into Scheme.
 309   */
 310 SCM
 311 Note_collision_interface::automatic_shift (Grob *me,
 312                             Drul_array< Link_array <Grob> >
 313                             clash_groups)
 314 {
 315   Drul_array<Array<int> > shifts;
 316   SCM  tups = SCM_EOL;
 317
 318
 319   Direction d = UP;
 320   do
 321     {
 322       Array<int> & shift (shifts[d]);
 323       Link_array<Grob> & clashes (clash_groups[d]);
 324
 325       for (int i=0; i < clashes.size (); i++)
 326         {
 327           SCM sh
 328             = clashes[i]->get_grob_property ("horizontal-shift");
 329
 330           if (gh_number_p (sh))
 331             shift.push (gh_scm2int (sh));
 332           else
 333             shift.push (0);
 334         }
 335
 336       for (int i=1; i < shift.size (); i++)
 337         {
 338           if (shift[i-1] == shift[i])
 339             {
 340               clashes[0]->warning (_ ("Too many clashing notecolumns.  Ignoring them."));
 341               return tups;
 342             }
 343         }
 344     }
 345   while ((flip (&d))!= UP);
 346
 347   Drul_array< Array < Slice > > extents;
 348   Drul_array< Array < Real > > offsets;
 349   d = UP;
 350   do
 351     {
 352       for (int i=0; i < clash_groups[d].size (); i++)
 353         {
 354           Slice s (Note_column::head_positions_interval (clash_groups[d][i]));
 355           s[LEFT] --;
 356           s[RIGHT]++;
 357           extents[d].push (s);
 358           offsets[d].push (d * 0.5 * i);
 359         }
 360     }
 361   while ((flip (&d))!= UP);
 362
 363   /*
 364     do horizontal shifts of each direction
 365
 366        |
 367       x||
 368        x||
 369         x|
 370    */
 371
 372   do
 373     {
 374       for (int i=1; i < clash_groups[d].size (); i++)
 375         {
 376           Slice prev =extents[d][i-1];
 377           prev.intersect (extents[d][i]);
 378           if (prev.length ()> 0 ||
 379  (extents[-d].size () && d * (extents[d][i][-d] - extents[-d][0][d]) < 0))
 380             for (int j = i; j <  clash_groups[d].size (); j++)
 381               offsets[d][j] += d * 0.5;
 382         }
 383     }
 384   while ((flip (&d))!= UP);
 385
 386
 387   /*
 388     Check if chords are meshing
 389    */
 390
 391   check_meshing_chords (me, &offsets, extents, clash_groups);
 392
 393   do
 394     {
 395       for (int i=0; i < clash_groups[d].size (); i++)
 396         tups = gh_cons (gh_cons (clash_groups[d][i]->self_scm (), gh_double2scm (offsets[d][i])),
 397                                  tups);
 398     }
 399   while (flip (&d) != UP);
 400   return tups;
 401 }
 402
 403
 404 SCM
 405 Note_collision_interface::forced_shift (Grob *me)
 406 {
 407   SCM tups = SCM_EOL;
 408
 409   SCM s = me->get_grob_property ("elements");
 410   for (; gh_pair_p (s); s = ly_cdr (s))
 411     {
 412       Grob * se = unsmob_grob (ly_car (s));
 413
 414       SCM force =  se->get_grob_property ("force-hshift");
 415       if (gh_number_p (force))
 416         {
 417           tups = gh_cons (gh_cons (se->self_scm (), force),
 418                           tups);
 419         }
 420     }
 421   return tups;
 422 }
 423
 424 void
 425 Note_collision_interface::add_column (Grob*me,Grob* ncol)
 426 {
 427   ncol->add_offset_callback (Note_collision_interface::force_shift_callback_proc, X_AXIS);
 428   Axis_group_interface::add_element (me, ncol);
 429   me->add_dependency (ncol);
 430 }
 431
 432
 433 ADD_INTERFACE (Note_collision_interface, "note-collision-interface",
 434   "An object that handles collisions between notes with different stem "
 435 "directions and horizontal shifts. Most of the interesting properties "
 436 "are to be set in @ref{note-column-interface}: these are "
 437 "@code{force-hshift} and @code{horizontal-shift}. ",
 438   "merge-differently-dotted merge-differently-headed collision-done");