lily/slur-scoring.cc

   1 /*
   2   slur-scoring.cc -- Score based slur formatting
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include <math.h>
  11
  12 #include "libc-extension.hh"
  13 #include "slur-configuration.hh"
  14 #include "slur-scoring.hh"
  15 #include "beam.hh"
  16 #include "directional-element-interface.hh"
  17 #include "group-interface.hh"
  18 #include "lily-guile.hh"
  19 #include "slur.hh"
  20 #include "note-column.hh"
  21 #include "output-def.hh"
  22 #include "pitch.hh"
  23 #include "bezier.hh"
  24 #include "spanner.hh"
  25 #include "staff-symbol-referencer.hh"
  26 #include "staff-symbol.hh"
  27 #include "stem.hh"
  28 #include "warn.hh"
  29 #include "paper-column.hh"
  30 #include "accidental-interface.hh"
  31
  32 /*
  33   TODO:
  34
  35   - curve around flag for y coordinate
  36
  37   - this file is a mess, clean it up
  38
  39   - short-cut: try a smaller region first.
  40
  41   - handle non-visible stems better.
  42
  43   - try to prune number of scoring criteria
  44
  45   - take encompass-objects more into account when determining
  46   slur shape
  47
  48   - calculate encompass scoring directly after determining slur shape.
  49
  50   - optimize.
  51
  52 */
  53 struct Slur_score_state;
  54
  55 Slur_score_state::Slur_score_state()
  56 {
  57   musical_dy_ = 0.0;
  58   valid_ = false;
  59   edge_has_beams_ = false;
  60   has_same_beam_ = false;
  61   is_broken_ = false;
  62   dir_ = CENTER;
  63   slur_ = 0;
  64   common_[X_AXIS] = 0;
  65   common_[Y_AXIS] = 0;
  66 }
  67
  68 Slur_score_state::~Slur_score_state ()
  69 {
  70   junk_pointers (configurations_);
  71 }
  72
  73 Real
  74 get_detail (SCM alist, SCM sym)
  75 {
  76   SCM entry = scm_assq (sym, alist);
  77   return robust_scm2double (scm_is_pair (entry)
  78                             ? scm_cdr (entry)
  79                             : SCM_EOL,
  80                             0.0);
  81 }
  82
  83 void
  84 Slur_score_parameters::fill (Grob *me)
  85 {
  86   SCM details = me->get_property ("slur-details");
  87
  88   region_size_
  89     = (int) get_detail (details, ly_symbol2scm ("region-size"));
  90   head_encompass_penalty_
  91     = get_detail (details, ly_symbol2scm ("head-encompass-penalty"));
  92   stem_encompass_penalty_
  93     = get_detail (details, ly_symbol2scm ("stem-encompass-penalty"));
  94   closeness_factor_
  95     = get_detail (details, ly_symbol2scm ("closeness-factor"));
  96   edge_attraction_factor_
  97     = get_detail (details, ly_symbol2scm ("edge-attraction-factor"));
  98   same_slope_penalty_
  99     = get_detail (details, ly_symbol2scm ("same-slope-penalty"));
 100   steeper_slope_factor_
 101     = get_detail (details, ly_symbol2scm ("steeper-slope-factor"));
 102   non_horizontal_penalty_
 103     = get_detail (details, ly_symbol2scm ("non-horizontal-penalty"));
 104   max_slope_
 105     = get_detail (details, ly_symbol2scm ("max-slope"));
 106   max_slope_factor_
 107     = get_detail (details, ly_symbol2scm ("max-slope-factor"));
 108   free_head_distance_
 109     = get_detail (details, ly_symbol2scm ("free-head-distance"));
 110   absolute_closeness_measure_
 111     = get_detail (details, ly_symbol2scm ("absolute-closeness-measure"));
 112   extra_object_collision_
 113     = get_detail (details, ly_symbol2scm ("extra-object-collision"));
 114   accidental_collision_
 115     = get_detail (details, ly_symbol2scm ("accidental-collision"));
 116   extra_encompass_free_distance_
 117     = get_detail (details, ly_symbol2scm ("extra-encompass-free-distance"));
 118   head_slur_distance_factor_
 119     = get_detail (details, ly_symbol2scm ("head-slur-distance-factor"));
 120   head_slur_distance_max_ratio_
 121     = get_detail (details, ly_symbol2scm ("head-slur-distance-max-ratio"));
 122   free_slur_distance_
 123     = get_detail (details, ly_symbol2scm ("free-slur-distance"));
 124   edge_slope_exponent_
 125     = get_detail (details, ly_symbol2scm ("edge-slope-exponent"));
 126 }
 127
 128 Real
 129 broken_trend_y (Slur_score_state const &state, Direction hdir)
 130 {
 131   /* A broken slur should maintain the same vertical trend
 132      the unbroken slur would have had.  */
 133   Real by = 0.0;
 134   if (Spanner *mother = dynamic_cast<Spanner*> (state.slur_->original_))
 135     {
 136       int k = broken_spanner_index (state.slur_);
 137       int j = k + hdir;
 138       if (j < 0 || j >= mother->broken_intos_.size ())
 139         return by;
 140
 141       Grob *neighbor = mother->broken_intos_[j];
 142       Spanner *common_mother
 143         = dynamic_cast<Spanner*> (state.common_[Y_AXIS]->original_);
 144       int common_k
 145         = broken_spanner_index (dynamic_cast<Spanner*> (state.common_[Y_AXIS]));
 146       int common_j = common_k + hdir;
 147
 148       if (common_j < 0 || common_j >= common_mother->broken_intos_.size ())
 149         return by;
 150
 151       Grob *common_next_system = common_mother->broken_intos_[common_j];
 152
 153       SCM last_point =  scm_car (scm_last_pair (neighbor->get_property ("control-points")));
 154
 155       return scm_to_double (scm_cdr (last_point))
 156         + neighbor->relative_coordinate (common_next_system, Y_AXIS);
 157     }
 158   return by;
 159 }
 160
 161
 162 /*
 163   copy slur dir forwards across line break.
 164 */
 165 void
 166 Slur_score_state::set_next_direction ()
 167 {
 168   if (extremes_[RIGHT].note_column_)
 169     return;
 170
 171   if (Spanner *mother = dynamic_cast<Spanner*> (slur_->original_))
 172     {
 173       int k = broken_spanner_index (slur_);
 174       int j = k + 1;
 175       if (j < 0 || j >= mother->broken_intos_.size ())
 176         return;
 177
 178       Grob *neighbor = mother->broken_intos_[j];
 179       set_grob_direction (neighbor, dir_);
 180     }
 181 }
 182
 183 Encompass_info
 184 Slur_score_state::get_encompass_info (Grob *col) const
 185 {
 186   Grob *stem = unsmob_grob (col->get_property ("stem"));
 187   Encompass_info ei;
 188
 189   if (!stem)
 190     {
 191       programming_error ("No stem for note column?");
 192       ei.x_ = col->relative_coordinate (common_[X_AXIS], X_AXIS);
 193       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS],
 194                                          Y_AXIS)[dir_];
 195       return ei;
 196     }
 197   Direction stem_dir = get_grob_direction (stem);
 198
 199   if (Grob *head = Note_column::first_head (col))
 200     ei.x_ = head->extent (common_[X_AXIS], X_AXIS).center ();
 201   else
 202     ei.x_ = col->extent (common_[X_AXIS], X_AXIS).center ();
 203
 204   Grob *h = Stem::extremal_heads (stem)[Direction (dir_)];
 205   if (!h)
 206     {
 207       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 208       return ei;
 209     }
 210
 211   ei.head_ = h->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 212
 213   if ((stem_dir == dir_)
 214       && !stem->extent (stem, Y_AXIS).is_empty ())
 215     {
 216       ei.stem_ = stem->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 217       if (Grob *b = Stem::get_beam (stem))
 218         ei.stem_ += stem_dir * 0.5 * Beam::get_thickness (b);
 219
 220       Interval x = stem->extent (common_[X_AXIS], X_AXIS);
 221       ei.x_ = x.is_empty ()
 222         ? stem->relative_coordinate (common_[X_AXIS], X_AXIS)
 223         : x.center ();
 224     }
 225   else
 226     ei.stem_ = ei.head_;
 227
 228   return ei;
 229 }
 230
 231
 232
 233
 234 Drul_array<Bound_info>
 235 Slur_score_state::get_bound_info () const
 236 {
 237   Drul_array<Bound_info> extremes;
 238
 239   Direction d = LEFT;
 240   Direction dir = dir_;
 241
 242   do
 243     {
 244       extremes[d].bound_ = slur_->get_bound (d);
 245       if (Note_column::has_interface (extremes[d].bound_))
 246         {
 247           extremes[d].note_column_ = extremes[d].bound_;
 248           extremes[d].stem_ = Note_column::get_stem (extremes[d].note_column_);
 249           extremes[d].stem_dir_ = get_grob_direction (extremes[d].stem_);
 250           extremes[d].stem_extent_[X_AXIS]
 251             = extremes[d].stem_->extent (common_[X_AXIS], X_AXIS);
 252           extremes[d].stem_extent_[Y_AXIS]
 253             = extremes[d].stem_->extent (common_[Y_AXIS], Y_AXIS);
 254           extremes[d].slur_head_
 255             = Stem::extremal_heads (extremes[d].stem_)[dir];
 256           if (!extremes[d].slur_head_
 257               && Note_column::has_rests (extremes[d].bound_))
 258             {
 259               extremes[d].slur_head_ = Note_column::get_rest (extremes[d].bound_);
 260             }
 261
 262           if (extremes[d].slur_head_)
 263             extremes[d].slur_head_extent_
 264               = extremes[d].slur_head_->extent (common_[X_AXIS], X_AXIS);
 265
 266           extremes[d].staff_ = Staff_symbol_referencer
 267             ::get_staff_symbol (extremes[d].stem_);
 268           extremes[d].staff_space_ = Staff_symbol_referencer
 269             ::staff_space (extremes[d].stem_);
 270         }
 271     }
 272   while (flip (&d) != LEFT);
 273   return extremes;
 274 }
 275
 276 void
 277 Slur_score_state::fill (Grob *me)
 278 {
 279   slur_ = dynamic_cast<Spanner*> (me);
 280   columns_
 281     = Pointer_group_interface__extract_grobs (me, (Grob *) 0, "note-columns");
 282
 283   if (columns_.is_empty ())
 284     {
 285       me->suicide ();
 286       return ;
 287     }
 288
 289   staff_space_ = Staff_symbol_referencer::staff_space (me);
 290   Real lt = me->get_layout ()->get_dimension (ly_symbol2scm ("linethickness"));
 291   thickness_ = robust_scm2double (me->get_property ("thickness"), 1.0) *  lt;
 292
 293   dir_ = get_grob_direction (me);
 294   parameters_.fill (me);
 295
 296   SCM eltlist = me->get_property ("note-columns");
 297   SCM extra_list = me->get_property ("encompass-objects");
 298   Spanner *sp = dynamic_cast<Spanner*> (me);
 299
 300   for (int i = X_AXIS; i < NO_AXES; i++)
 301     {
 302       Axis a = (Axis)i;
 303       common_[a] = common_refpoint_of_list (eltlist, me, a);
 304       common_[a] = common_refpoint_of_list (extra_list, common_[a], a);
 305
 306       Direction d = LEFT;
 307       do {
 308         /*
 309           If bound is not in note-columns, we don't want to know about
 310           its Y-position
 311          */
 312         if (a != Y_AXIS)
 313           common_[a] = common_[a]->common_refpoint (sp->get_bound (d), a);
 314       }
 315       while (flip (&d) != LEFT);
 316     }
 317
 318   extremes_ = get_bound_info ();
 319   is_broken_ = (!extremes_[LEFT].note_column_
 320                 || !extremes_[RIGHT].note_column_);
 321
 322
 323   base_attachments_ = get_base_attachments ();
 324
 325   Drul_array<Real> end_ys
 326     = get_y_attachment_range ();
 327
 328   configurations_ = enumerate_attachments ( end_ys);
 329   for (int i = 0; i < columns_.size (); i++)
 330     encompass_infos_.push (get_encompass_info ( columns_[i]));
 331
 332   extra_encompass_infos_ = get_extra_encompass_infos ();
 333   valid_ = true;
 334
 335
 336   musical_dy_ = 0.0;
 337   Direction d = LEFT;
 338   do
 339     {
 340       if (!is_broken_)
 341         musical_dy_ += d
 342           * extremes_[d].slur_head_->relative_coordinate (common_[Y_AXIS], Y_AXIS);
 343     }
 344   while (flip (&d) != LEFT);
 345
 346   edge_has_beams_
 347     = (extremes_[LEFT].stem_ && Stem::get_beam (extremes_[LEFT].stem_))
 348     || (extremes_[RIGHT].stem_ && Stem::get_beam (extremes_[RIGHT].stem_));
 349
 350   has_same_beam_ =
 351     (extremes_[LEFT].stem_ && extremes_[RIGHT].stem_
 352      && Stem::get_beam (extremes_[LEFT].stem_) == Stem::get_beam (extremes_[RIGHT].stem_));
 353
 354
 355   set_next_direction ();
 356
 357   if (is_broken_)
 358     musical_dy_ = 0.0;
 359 }
 360
 361 void
 362 set_slur_control_points (Grob *me)
 363 {
 364   Slur_score_state state;
 365   state.fill (me);
 366
 367   if (!state.valid_)
 368     return;
 369
 370   state.generate_curves ();
 371   Bezier best (state.get_best_curve());
 372
 373
 374   SCM controls = SCM_EOL;
 375   for (int i = 4; i--;)
 376     {
 377       Offset o = best.control_[i]
 378         - Offset (me->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 379                   me->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 380       controls = scm_cons (ly_offset2scm (o), controls);
 381     }
 382   me->set_property ("control-points", controls);
 383 }
 384
 385
 386 Bezier
 387 Slur_score_state::get_best_curve ()
 388 {
 389   for (int i = 0; i < configurations_.size (); i++)
 390     {
 391       configurations_[i]->score (*this);
 392     }
 393
 394   Real opt = 1e6;
 395   int opt_idx = -1;
 396   for (int i = 0; i < configurations_.size (); i++)
 397     {
 398       if (configurations_[i]->score_ < opt)
 399         {
 400           opt = configurations_[i]->score_;
 401           opt_idx = i;
 402         }
 403     }
 404
 405 #if DEBUG_SLUR_SCORING
 406   SCM inspect_quants = slur_->get_property ("inspect-quants");
 407   if (to_boolean (slur_->get_layout ()
 408                   ->lookup_variable (ly_symbol2scm ("debug-slur-scoring")))
 409       && scm_is_pair (inspect_quants))
 410     {
 411       Drul_array<Real> ins = ly_scm2interval (inspect_quants);
 412       Real mindist = 1e6;
 413       for (int i = 0; i < configurations_.size (); i ++)
 414         {
 415           Real d =fabs (configurations_[i]->attachment_[LEFT][Y_AXIS] - ins[LEFT])
 416             + fabs (configurations_[i]->attachment_[RIGHT][Y_AXIS] - ins[RIGHT]);
 417           if (d < mindist)
 418             {
 419               opt_idx = i;
 420               mindist= d;
 421             }
 422         }
 423       if (mindist > 1e5)
 424         programming_error ("Could not find quant.");
 425     }
 426
 427   configurations_[opt_idx]->score_card_ += to_string ("=%.2f", opt);
 428   configurations_[opt_idx]->score_card_ += to_string ("i%d", opt_idx);
 429
 430   // debug quanting
 431   slur_->set_property ("quant-score",
 432                     scm_makfrom0str (configurations_[opt_idx]->score_card_.to_str0 ()));
 433
 434 #endif
 435
 436   return configurations_[opt_idx]->curve_;
 437 }
 438
 439 /*
 440   TODO: should analyse encompasses to determine sensible region, and
 441   should limit slopes available.
 442  */
 443
 444 Drul_array<Real>
 445 Slur_score_state::get_y_attachment_range () const
 446 {
 447   Drul_array<Real> end_ys;
 448   Direction d = LEFT;
 449   do
 450     {
 451       if (extremes_[d].note_column_)
 452         {
 453           end_ys[d] = dir_
 454             * ((dir_ * (base_attachments_[d][Y_AXIS] +  parameters_.region_size_* dir_))
 455                >? (dir_ * (dir_ + extremes_[d].note_column_->extent (common_[Y_AXIS],
 456                                                                  Y_AXIS)[dir_]))
 457                >? (dir_ * base_attachments_[-d][Y_AXIS]));
 458         }
 459       else
 460         end_ys[d] = base_attachments_[d][Y_AXIS] + parameters_.region_size_ * dir_;
 461     }
 462   while (flip (&d) != LEFT);
 463
 464   return end_ys;
 465 }
 466
 467 bool
 468 spanner_less (Spanner *s1, Spanner* s2)
 469 {
 470   Slice b1, b2;
 471   Direction d  = LEFT;
 472   do
 473     {
 474       b1[d] = s1->get_bound (d)->get_column ()->rank_;
 475       b2[d] = s2->get_bound (d)->get_column ()->rank_;
 476     } while (flip (&d) != LEFT);
 477
 478   return b2[LEFT] <= b1[LEFT] && b2[RIGHT] >= b1[RIGHT]
 479     && (b2[LEFT] != b1[LEFT] || b2[RIGHT] != b1[RIGHT]);
 480 }
 481
 482
 483 Drul_array<Offset>
 484 Slur_score_state::get_base_attachments () const
 485 {
 486   Drul_array<Offset> base_attachment;
 487   Direction d = LEFT;
 488   do
 489     {
 490       Grob *stem = extremes_[d].stem_;
 491       Grob *head = extremes_[d].slur_head_;
 492
 493       Real x = 0.0;
 494       Real y = 0.0;
 495       if (extremes_[d].note_column_)
 496         {
 497
 498           /*
 499             fixme: X coord should also be set in this case.
 500            */
 501           if (stem
 502               && extremes_[d].stem_dir_ == dir_
 503               && Stem::get_beaming (stem, -d)
 504               && (!spanner_less (slur_, Stem::get_beam (stem))
 505                   || has_same_beam_))
 506             y = extremes_[d].stem_extent_[Y_AXIS][dir_];
 507           else if (head)
 508             y = head->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 509           y += dir_ * 0.5 * staff_space_;
 510
 511
 512           y = move_away_from_staffline (y, head);
 513
 514           Grob * fh = Note_column::first_head (extremes_[d].note_column_);
 515           x =
 516          (fh ? fh->extent (common_[X_AXIS], X_AXIS)
 517              : extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS))
 518             .linear_combination (CENTER);
 519         }
 520       base_attachment[d] = Offset (x, y);
 521
 522     } while (flip (&d) != LEFT);
 523
 524   do
 525     {
 526       if (!extremes_[d].note_column_)
 527         {
 528           Real x, y;
 529           if (d == RIGHT)
 530             {
 531               x = extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS)[d];
 532             }
 533           else
 534             {
 535               x = slur_->get_broken_left_end_align ();
 536             }
 537           Grob * col = (d == LEFT) ? columns_[0] : columns_.top();
 538
 539           if (extremes_[-d].bound_ != col)
 540             {
 541               y = robust_relative_extent (col, common_[Y_AXIS], Y_AXIS)[dir_];
 542               y += dir_ * 0.5 * staff_space_;
 543
 544               if (get_grob_direction (col) == dir_
 545                   && Note_column::get_stem (col)
 546                   && !Stem::is_invisible (Note_column::get_stem (col)))
 547                 y -= dir_ * 1.5 * staff_space_;
 548             }
 549           else
 550             y = base_attachment[-d][Y_AXIS];
 551
 552
 553           y = move_away_from_staffline (y, col);
 554
 555           base_attachment[d] = Offset (x, y);
 556         }
 557     }
 558   while (flip (&d) != LEFT);
 559
 560   return base_attachment;
 561 }
 562
 563 Real
 564 Slur_score_state::move_away_from_staffline (Real y,
 565                                             Grob *on_staff) const
 566 {
 567   Real pos
 568     = (y - Staff_symbol_referencer::get_staff_symbol (on_staff)->relative_coordinate (common_[Y_AXIS],
 569                                                                                Y_AXIS))
 570     * 2.0 / staff_space_;
 571
 572   if (fabs (pos - my_round (pos)) < 0.2
 573       && Staff_symbol_referencer::on_staffline (on_staff, (int) rint (pos))
 574       && Staff_symbol_referencer::line_count (on_staff) - 1 >= rint (pos)
 575       )
 576     y += 1.5 * staff_space_ * dir_ / 10;
 577
 578   return y;
 579 }
 580
 581 void
 582 Slur_score_state::generate_curves () const
 583 {
 584   Real r_0 = robust_scm2double (slur_->get_property ("ratio"), 0.33);
 585   Real h_inf = staff_space_ *scm_to_double (slur_->get_property ("height-limit"));
 586   for (int i = 0; i < configurations_.size (); i++)
 587     configurations_[i]->generate_curve (*this, r_0, h_inf);
 588 }
 589
 590
 591
 592
 593 Link_array<Slur_configuration>
 594 Slur_score_state::enumerate_attachments (Drul_array<Real> end_ys) const
 595 {
 596   /*ugh.   */
 597   Link_array<Slur_configuration> scores;
 598
 599
 600   Drul_array<Offset> os;
 601   os[LEFT] = base_attachments_[LEFT];
 602   Real minimum_length = staff_space_
 603     * robust_scm2double (slur_->get_property ("minimum-length"), 2.0);
 604
 605   for (int i = 0; dir_ * os[LEFT][Y_AXIS] <= dir_ * end_ys[LEFT]; i++)
 606     {
 607       os[RIGHT] = base_attachments_[RIGHT];
 608       for (int j = 0; dir_ * os[RIGHT][Y_AXIS] <= dir_ * end_ys[RIGHT]; j++)
 609         {
 610           Slur_configuration s;
 611           Direction d = LEFT;
 612           Drul_array<bool> attach_to_stem (false, false);
 613           do
 614             {
 615               os[d][X_AXIS] = base_attachments_[d][X_AXIS];
 616               if (extremes_[d].stem_
 617                   && !Stem::is_invisible (extremes_[d].stem_)
 618                   && extremes_[d].stem_dir_ == dir_)
 619                 {
 620                   Interval stem_y = extremes_[d].stem_extent_[Y_AXIS];
 621                   stem_y.widen (0.25 * staff_space_);
 622                   if (dir_ == -d
 623                       && stem_y.contains (os[d][Y_AXIS]))
 624                     {
 625                       os[d][X_AXIS] =  extremes_[d].slur_head_extent_[-d]
 626                         - d * 0.3;
 627                       attach_to_stem[d] = true;
 628                     }
 629                   else if (dir_ *extremes_[d].stem_extent_[Y_AXIS][dir_]
 630                              < dir_ * os[d][Y_AXIS]
 631                            && !extremes_[d].stem_extent_[X_AXIS].is_empty ()
 632                            )
 633
 634                     os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS].center ();
 635                 }
 636             }
 637           while (flip (&d) != LEFT);
 638
 639           Offset dz;
 640           dz = os[RIGHT] - os[LEFT];
 641           if (dz[X_AXIS] < minimum_length
 642               || fabs (dz[Y_AXIS] / dz[X_AXIS]) > parameters_.max_slope_
 643               )
 644             {
 645               do
 646                 {
 647                   if (extremes_[d].slur_head_)
 648                     {
 649                       os[d][X_AXIS] = extremes_[d].slur_head_extent_.center ();
 650                       attach_to_stem[d] = false;
 651                     }
 652                 }
 653               while (flip (&d) != LEFT);
 654             }
 655
 656           dz = os[RIGHT] - os[LEFT];
 657           do
 658             {
 659               if (extremes_[d].slur_head_
 660                   && !attach_to_stem[d])
 661                 {
 662                   /* Horizontally move tilted slurs a little.  Move
 663                      more for bigger tilts.
 664
 665                      TODO: parameter */
 666                   os[d][X_AXIS]
 667                     -= dir_ * extremes_[d].slur_head_extent_.length ()
 668                     * sin (dz.arg ()) / 3;
 669                 }
 670             }
 671           while (flip (&d) != LEFT);
 672
 673           s.attachment_ = os;
 674           s.index_ = scores.size ();
 675
 676           scores.push (new Slur_configuration (s));
 677
 678           os[RIGHT][Y_AXIS] += dir_ * staff_space_ / 2;
 679         }
 680
 681       os[LEFT][Y_AXIS] += dir_ * staff_space_ / 2;
 682     }
 683
 684   assert (scores.size () > 0);
 685   return scores;
 686 }
 687
 688
 689 Array<Extra_collision_info>
 690 Slur_score_state::get_extra_encompass_infos () const
 691 {
 692   Link_array<Grob> encompasses
 693     = Pointer_group_interface__extract_grobs (slur_, (Grob *)0,
 694                                               "encompass-objects");
 695   Array<Extra_collision_info> collision_infos;
 696   for (int i = encompasses.size (); i--; )
 697     {
 698       if (Slur::has_interface (encompasses[i]))
 699         {
 700           Spanner * small_slur = dynamic_cast<Spanner*> (encompasses[i]);
 701           Bezier b = Slur::get_curve (small_slur);
 702
 703           Offset relative (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 704                            small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 705
 706           for (int k = 0; k < 3; k++)
 707             {
 708               Direction hdir =  Direction (k /2 - 1);
 709
 710               /*
 711                 Only take bound into account if small slur starts
 712                 together with big slur.
 713               */
 714               if (hdir && small_slur->get_bound (hdir) != slur_->get_bound (hdir))
 715                 continue;
 716
 717               Offset z = b.curve_point (k / 2.0);
 718               z += relative;
 719
 720               Interval yext;
 721               yext.set_full ();
 722               yext[dir_] = z[Y_AXIS] + dir_ * thickness_ * 1.0;
 723
 724               Interval xext (-1, 1);
 725               xext = xext * (thickness_*2) + z[X_AXIS];
 726               Extra_collision_info info (small_slur,
 727                                          k - 1.0,
 728                                          xext,
 729                                          yext,
 730                                          parameters_.extra_object_collision_);
 731               collision_infos.push (info);
 732             }
 733         }
 734       else
 735         {
 736           Grob *g = encompasses [i];
 737           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 738           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 739
 740           Real xp = 0.0;
 741           Real penalty = parameters_.extra_object_collision_;
 742           if (Accidental_interface::has_interface (g))
 743             {
 744               penalty = parameters_.accidental_collision_;
 745               /* Begin copy accidental.cc */
 746               bool parens = false;
 747               if (to_boolean (g->get_property ("cautionary")))
 748                 {
 749                   SCM cstyle = g->get_property ("cautionary-style");
 750                   parens = ly_c_equal_p (cstyle, ly_symbol2scm ("parentheses"));
 751                 }
 752
 753               SCM accs = g->get_property ("accidentals");
 754               SCM scm_style = g->get_property ("style");
 755               if (!scm_is_symbol (scm_style)
 756                   && !parens
 757                   && scm_ilength (accs) == 1)
 758                 {
 759                   /* End copy accidental.cc */
 760                   switch (scm_to_int (scm_car (accs)))
 761                     {
 762                     case FLAT:
 763                     case DOUBLE_FLAT:
 764                       xp = LEFT;
 765                       break ;
 766                     case SHARP:
 767                       xp = 0.5 * dir_;
 768                       break ;
 769                     case NATURAL:
 770                       xp = -dir_;
 771                       break;
 772                     }
 773                 }
 774             }
 775
 776           ye.widen (thickness_ * 0.5);
 777           xe.widen (thickness_ * 1.0);
 778           Extra_collision_info info (g, xp, xe, ye,  penalty);
 779           collision_infos.push (info);
 780         }
 781     }
 782
 783   return collision_infos;
 784 }
 785