lily/note-collision.cc

   1 /*
   2   collision.cc -- implement Collision
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "note-collision.hh"
  10
  11 #include "axis-group-interface.hh"
  12 #include "dot-column.hh"
  13 #include "international.hh"
  14 #include "note-column.hh"
  15 #include "note-head.hh"
  16 #include "output-def.hh"
  17 #include "pointer-group-interface.hh"
  18 #include "item.hh"
  19 #include "rhythmic-head.hh"
  20 #include "staff-symbol-referencer.hh"
  21 #include "side-position-interface.hh"
  22 #include "stem.hh"
  23 #include "warn.hh"
  24
  25
  26 void
  27 check_meshing_chords (Grob *me,
  28                       Drul_array<vector<Real> > *offsets,
  29                       Drul_array<vector<Slice> > const &extents,
  30                       Drul_array<vector<Grob*> > const &clash_groups)
  31
  32 {
  33   if (!extents[UP].size () || ! extents[DOWN].size ())
  34     return;
  35
  36   Grob *cu = clash_groups[UP][0];
  37   Grob *cd = clash_groups[DOWN][0];
  38
  39   /* Every note column should have a stem, but avoid a crash. */
  40   if (!Note_column::get_stem (cu) || !Note_column::get_stem (cd))
  41     return;
  42
  43   Drul_array<Grob*> stems (Note_column::get_stem (cd),
  44                            Note_column::get_stem (cu));
  45
  46   Grob *nu = Note_column::first_head (cu);
  47   Grob *nd = Note_column::first_head (cd);
  48
  49   vector<int> ups = Stem::note_head_positions (Note_column::get_stem (cu));
  50   vector<int> dps = Stem::note_head_positions (Note_column::get_stem (cd));
  51
  52   /* Too far apart to collide.  */
  53   if (ups[0] > dps.back () + 1)
  54     return;
  55
  56   /* Merge heads if the notes lie the same line, or if the "stem-up-note" is
  57      above the "stem-down-note". */
  58   bool merge_possible = (ups[0] >= dps[0]) && (ups.back () >= dps.back ());
  59
  60   /* Do not merge notes typeset in different style. */
  61   if (!ly_is_equal (nu->get_property ("style"),
  62                     nd->get_property ("style")))
  63     merge_possible = false;
  64
  65   int upball_type = Rhythmic_head::duration_log (nu);
  66   int dnball_type = Rhythmic_head::duration_log (nd);
  67
  68   /* Do not merge whole notes (or longer, like breve, longa, maxima).  */
  69   if (merge_possible && (upball_type <= 0 || dnball_type <= 0))
  70     merge_possible = false;
  71
  72   if (merge_possible
  73       && Rhythmic_head::dot_count (nu) != Rhythmic_head::dot_count (nd)
  74       && !to_boolean (me->get_property ("merge-differently-dotted")))
  75     merge_possible = false;
  76
  77   /* Can only merge different heads if merge-differently-headed is
  78      set. */
  79   if (merge_possible
  80       && upball_type != dnball_type
  81       && !to_boolean (me->get_property ("merge-differently-headed")))
  82     merge_possible = false;
  83
  84   if (merge_possible
  85       && nu->get_property ("style") == ly_symbol2scm ("fa")
  86       && nd->get_property ("style") == ly_symbol2scm ("fa"))
  87     {
  88       Interval uphead_size = nu->extent (nu, Y_AXIS);
  89       Offset att =  Offset (0.0, -1.0);
  90       nu->set_property ("stem-attachment", ly_offset2scm (att));
  91       nu->set_property ("transparent", SCM_BOOL_T);
  92     }
  93
  94   /* Should never merge quarter and half notes, as this would make
  95      them indistinguishable.  */
  96   if (merge_possible
  97       && ((Stem::duration_log (stems[UP]) == 1
  98            && Stem::duration_log (stems[DOWN]) == 2)
  99           || (Stem::duration_log (stems[UP]) == 2
 100               && Stem::duration_log (stems[DOWN]) == 1)))
 101     merge_possible = false;
 102
 103   /*
 104     this case (distant half collide),
 105
 106     |
 107     x |
 108     | x
 109     |
 110
 111     the noteheads may be closer than this case (close half collide)
 112
 113     |
 114     |
 115     x
 116     x
 117     |
 118     |
 119
 120   */
 121
 122   /* TODO: filter out the 'o's in this configuration, since they're no
 123      part in the collision.
 124
 125      |
 126      x|o
 127      x|o
 128      x
 129
 130   */
 131
 132   bool close_half_collide = false;
 133   bool distant_half_collide = false;
 134   bool full_collide = false;
 135
 136   for (vsize i = 0, j = 0; i < ups.size () && j < dps.size (); )
 137     {
 138       if (abs (ups[i] - dps[j]) == 1)
 139         {
 140           merge_possible = false;
 141           if (ups[i] > dps[j])
 142             close_half_collide = true;
 143           else
 144             distant_half_collide = true;
 145         }
 146       else if (ups[i] == dps[j])
 147         full_collide = true;
 148       else if (ups[i] > dps[0] && ups[i] < dps.back ())
 149         merge_possible = false;
 150       else if (dps[j] > ups[0] && dps[j] < ups.back ())
 151         merge_possible = false;
 152
 153       if (ups[i] < dps[j])
 154         i++;
 155       else if (ups[i] > dps[j])
 156         j++;
 157       else
 158         {
 159           i++;
 160           j++;
 161         }
 162     }
 163
 164   full_collide = full_collide || (close_half_collide
 165                                   && distant_half_collide);
 166
 167   Drul_array<Real> center_note_shifts;
 168   center_note_shifts[LEFT] = 0.0;
 169   center_note_shifts[RIGHT] = 0.0;
 170
 171   Real shift_amount = 1;
 172
 173   bool touch = (ups[0] >= dps.back ());
 174   if (touch)
 175     shift_amount *= -1;
 176
 177   /* For full collisions, the right hand head may obscure dots, so
 178      make sure the dotted heads go to the right.  */
 179   bool stem_to_stem = false;
 180   if (full_collide)
 181     if (Rhythmic_head::dot_count (nu) > Rhythmic_head::dot_count (nd))
 182       shift_amount = 1;
 183     else if (Rhythmic_head::dot_count (nu) < Rhythmic_head::dot_count (nd))
 184       stem_to_stem = true;
 185
 186   if (merge_possible)
 187     {
 188       shift_amount = 0;
 189
 190       /* If possible, don't wipe any heads. Else, wipe shortest head,
 191          or head with smallest amount of dots.  Note: when merging
 192          different heads, dots on the smaller one disappear. */
 193       Grob *wipe_ball = 0;
 194       Grob *dot_wipe_head = nu;
 195
 196       if (upball_type == dnball_type)
 197         {
 198           if (Rhythmic_head::dot_count (nd) < Rhythmic_head::dot_count (nu))
 199             {
 200               wipe_ball = nd;
 201               dot_wipe_head = nd;
 202             }
 203           else if (Rhythmic_head::dot_count (nd) > Rhythmic_head::dot_count (nu))
 204             {
 205               dot_wipe_head = nu;
 206               wipe_ball = nu;
 207             }
 208           else
 209             dot_wipe_head = nu;
 210         }
 211       else if (dnball_type > upball_type)
 212         {
 213           wipe_ball = nd;
 214           dot_wipe_head = nd;
 215         }
 216       else if (dnball_type < upball_type)
 217         {
 218           wipe_ball = nu;
 219           dot_wipe_head = nu;
 220         }
 221
 222       if (dot_wipe_head)
 223         {
 224           if (Grob *d = unsmob_grob (dot_wipe_head->get_object ("dot")))
 225             d->suicide ();
 226         }
 227
 228       if (wipe_ball && wipe_ball->is_live ())
 229         {
 230           wipe_ball->set_property ("transparent", SCM_BOOL_T);
 231         }
 232     }
 233   /* TODO: these numbers are magic; should devise a set of grob props
 234      to tune this behavior.  */
 235   else if (stem_to_stem)
 236     shift_amount = -abs (shift_amount) * 0.65;
 237   else if (close_half_collide && !touch)
 238     shift_amount *= 0.52;
 239   else if (distant_half_collide && !touch)
 240     shift_amount *= 0.4;
 241   else if (distant_half_collide || close_half_collide || full_collide)
 242     shift_amount *= 0.5;
 243
 244   /* we're meshing.  */
 245   else if (Rhythmic_head::dot_count (nu) || Rhythmic_head::dot_count (nd))
 246     shift_amount *= 0.1;
 247   else
 248     shift_amount *= 0.17;
 249
 250   /*
 251
 252   */
 253   if (full_collide
 254       && dnball_type * upball_type == 0)
 255     {
 256       if (upball_type == 0 && dnball_type == 1)
 257         shift_amount *= 1.25;
 258       else if (upball_type == 0 && dnball_type == 2)
 259         shift_amount *= 1.35;
 260       else if (dnball_type == 0 && upball_type == 1)
 261         shift_amount *= 0.7;
 262       else if (dnball_type == 0 && upball_type == 2)
 263         shift_amount *= 0.75;
 264     }
 265
 266   /*
 267    * Fix issue #44:
 268    *
 269    * Dots from left note head collide with right note head. Only occurs
 270    * with a close half collide, if the left note head is between
 271    * lines and the right note head is on a line, and if right note head
 272    * hasn't got any dots.
 273    */
 274   if (close_half_collide
 275       && Rhythmic_head::dot_count (nu)
 276       && !Rhythmic_head::dot_count (nd))
 277     {
 278       Grob *staff = Staff_symbol_referencer::get_staff_symbol (me);
 279       if (!Staff_symbol_referencer::on_line (staff, ups[0]))
 280         {
 281           Grob *d = unsmob_grob (nu->get_object ("dot"));
 282           Grob *parent = d->get_parent (X_AXIS);
 283           if (Dot_column::has_interface (parent))
 284             Side_position_interface::add_support (parent, nd);
 285         }
 286     }
 287
 288   /* For full or close half collisions, the right hand head may
 289      obscure dots.  Move dots to the right.  */
 290   if (abs (shift_amount) > 1e-6
 291       && Rhythmic_head::dot_count (nd) > Rhythmic_head::dot_count (nu)
 292       && (full_collide || close_half_collide))
 293     {
 294       Grob *d = unsmob_grob (nd->get_object ("dot"));
 295       Grob *parent = d->get_parent (X_AXIS);
 296
 297       /*
 298         FIXME:
 299
 300         |
 301         x . o
 302         |
 303
 304
 305         the . is put right of o which is erroneous o force-shifted
 306         far to the right.
 307       */
 308       if (Dot_column::has_interface (parent))
 309         {
 310           Grob *stem = unsmob_grob (nu->get_object ("stem"));
 311           extract_grob_set (stem, "note-heads", heads);
 312           for (vsize i = 0; i < heads.size (); i++)
 313             Side_position_interface::add_support (parent, heads[i]);
 314         }
 315     }
 316
 317   Direction d = UP;
 318   do
 319     {
 320       for (vsize i = 0; i < clash_groups[d].size (); i++)
 321         (*offsets)[d][i] += d * shift_amount;
 322     }
 323   while ((flip (&d)) != UP);
 324 }
 325
 326
 327 MAKE_SCHEME_CALLBACK (Note_collision_interface, calc_positioning_done, 1)
 328 SCM
 329 Note_collision_interface::calc_positioning_done (SCM smob)
 330 {
 331   Grob *me = unsmob_grob (smob);
 332   me->set_property ("positioning-done", SCM_BOOL_T);
 333
 334   Drul_array<vector<Grob*> > cg = get_clash_groups (me);
 335
 336   Direction d = UP;
 337   do
 338     {
 339       for (vsize i = cg[d].size (); i--; )
 340         {
 341           /*
 342             Trigger positioning
 343            */
 344           cg[d][i]->extent (me, X_AXIS);
 345         }
 346     }
 347   while (flip (&d) != UP);
 348
 349   SCM autos (automatic_shift (me, cg));
 350   SCM hand (forced_shift (me));
 351
 352   Real wid = 0.0;
 353   do
 354     {
 355       if (cg[d].size ())
 356         {
 357           Grob *h = cg[d][0];
 358           Grob *fh = Note_column::first_head (h);
 359           if (fh)
 360             wid = fh->extent (h, X_AXIS).length ();
 361         }
 362     }
 363   while (flip (&d) != UP);
 364
 365   vector<Grob*> done;
 366   Real left_most = 1e6;
 367
 368   vector<Real> amounts;
 369   for (; scm_is_pair (hand); hand = scm_cdr (hand))
 370     {
 371       Grob *s = unsmob_grob (scm_caar (hand));
 372       Real amount = scm_to_double (scm_cdar (hand)) * wid;
 373
 374       done.push_back (s);
 375       amounts.push_back (amount);
 376       if (amount < left_most)
 377         left_most = amount;
 378     }
 379   for (; scm_is_pair (autos); autos = scm_cdr (autos))
 380     {
 381       Grob *s = unsmob_grob (scm_caar (autos));
 382       Real amount = scm_to_double (scm_cdar (autos)) * wid;
 383
 384       vsize x = find (done, s) - done.begin ();
 385       if (x == VPOS || x >= done.size ())
 386         {
 387           done.push_back (s);
 388           amounts.push_back (amount);
 389           if (amount < left_most)
 390             left_most = amount;
 391         }
 392     }
 393
 394   for (vsize i = 0; i < amounts.size (); i++)
 395     done[i]->translate_axis (amounts[i] - left_most, X_AXIS);
 396
 397   return SCM_BOOL_T;
 398 }
 399
 400 Drul_array < vector<Grob*> >
 401 Note_collision_interface::get_clash_groups (Grob *me)
 402 {
 403   Drul_array<vector<Grob*> > clash_groups;
 404
 405   extract_grob_set (me, "elements", elements);
 406   for (vsize i = 0; i < elements.size (); i++)
 407     {
 408       Grob *se = elements[i];
 409       if (Note_column::has_interface (se))
 410         {
 411           if (!Note_column::dir (se))
 412             {
 413               se->programming_error ("note-column has no direction");
 414             }
 415           else
 416             clash_groups[Note_column::dir (se)].push_back (se);
 417         }
 418     }
 419
 420   Direction d = UP;
 421   do
 422     {
 423       vector<Grob*> &clashes (clash_groups[d]);
 424       vector_sort (clashes, Note_column::shift_less);
 425     }
 426   while ((flip (&d)) != UP);
 427
 428   return clash_groups;
 429 }
 430
 431 /** This complicated routine moves note columns around horizontally to
 432     ensure that notes don't clash.
 433
 434 */
 435 SCM
 436 Note_collision_interface::automatic_shift (Grob *me,
 437                                            Drul_array<vector<Grob*> > clash_groups)
 438 {
 439   Drul_array < vector<int> > shifts;
 440   SCM tups = SCM_EOL;
 441
 442   Direction d = UP;
 443   do
 444     {
 445       vector<int> &shift (shifts[d]);
 446       vector<Grob*> &clashes (clash_groups[d]);
 447
 448       for (vsize i = 0; i < clashes.size (); i++)
 449         {
 450           SCM sh
 451             = clashes[i]->get_property ("horizontal-shift");
 452
 453           if (scm_is_number (sh))
 454             shift.push_back (scm_to_int (sh));
 455           else
 456             shift.push_back (0);
 457         }
 458
 459       for (vsize i = 1; i < shift.size (); i++)
 460         {
 461           if (shift[i - 1] == shift[i])
 462             {
 463               clashes[0]->warning (_ ("ignoring too many clashing note columns"));
 464               return tups;
 465             }
 466         }
 467     }
 468   while ((flip (&d)) != UP);
 469
 470   Drul_array<vector<Slice> > extents;
 471   Drul_array<vector<Real> > offsets;
 472   d = UP;
 473   do
 474     {
 475       for (vsize i = 0; i < clash_groups[d].size (); i++)
 476         {
 477           Slice s (Note_column::head_positions_interval (clash_groups[d][i]));
 478           s[LEFT]--;
 479           s[RIGHT]++;
 480           extents[d].push_back (s);
 481           offsets[d].push_back (d * 0.5 * i);
 482         }
 483     }
 484   while ((flip (&d)) != UP);
 485
 486   /*
 487     do horizontal shifts of each direction
 488
 489     |
 490     x||
 491     x||
 492     x|
 493   */
 494
 495   do
 496     {
 497       for (vsize i = 1; i < clash_groups[d].size (); i++)
 498         {
 499           Slice prev = extents[d][i - 1];
 500           prev.intersect (extents[d][i]);
 501           if (prev.length () > 0
 502               || (extents[-d].size () && d * (extents[d][i][-d] - extents[-d][0][d]) < 0))
 503             for (vsize j = i; j < clash_groups[d].size (); j++)
 504               offsets[d][j] += d * 0.5;
 505         }
 506     }
 507   while ((flip (&d)) != UP);
 508
 509
 510   /*
 511     see input/regression/dot-up-voice-collision.ly
 512    */
 513   for (vsize i = 0; i < clash_groups[UP].size (); i++)
 514     {
 515       Grob *g = clash_groups[UP][i];
 516       Grob *dc = Note_column::dot_column (g);
 517
 518       if (dc)
 519         for (vsize j = i + 1;  j < clash_groups[UP].size (); j++)
 520           {
 521             Grob *stem = Note_column::get_stem (clash_groups[UP][j]);
 522             Side_position_interface::add_support (dc, stem);
 523           }
 524     }
 525
 526   /*
 527     Check if chords are meshing
 528   */
 529
 530   check_meshing_chords (me, &offsets, extents, clash_groups);
 531
 532   do
 533     {
 534       for (vsize i = 0; i < clash_groups[d].size (); i++)
 535         tups = scm_cons (scm_cons (clash_groups[d][i]->self_scm (),
 536                                    scm_from_double (offsets[d][i])),
 537                          tups);
 538     }
 539   while (flip (&d) != UP);
 540
 541   return tups;
 542 }
 543
 544 SCM
 545 Note_collision_interface::forced_shift (Grob *me)
 546 {
 547   SCM tups = SCM_EOL;
 548
 549   extract_grob_set (me, "elements", elements);
 550   for (vsize i = 0; i < elements.size (); i++)
 551     {
 552       Grob *se = elements[i];
 553
 554       SCM force = se->get_property ("force-hshift");
 555       if (scm_is_number (force))
 556         {
 557           tups = scm_cons (scm_cons (se->self_scm (), force),
 558                            tups);
 559         }
 560     }
 561   return tups;
 562 }
 563
 564 void
 565 Note_collision_interface::add_column (Grob *me, Grob *ncol)
 566 {
 567   ncol->set_property ("X-offset", Grob::x_parent_positioning_proc);
 568   Axis_group_interface::add_element (me, ncol);
 569 }
 570
 571 ADD_INTERFACE (Note_collision_interface,
 572                "An object that handles collisions between notes with different stem "
 573                "directions and horizontal shifts. Most of the interesting properties "
 574                "are to be set in @ref{note-column-interface}: these are "
 575                "@code{force-hshift} and @code{horizontal-shift}.",
 576
 577                /* properties */
 578                "ignore-collision "
 579                "merge-differently-dotted "
 580                "merge-differently-headed "
 581                "positioning-done ");