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--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include <math.h>
  11
  12 #include "slur-scoring.hh"
  13 #include "libc-extension.hh"
  14 #include "slur-configuration.hh"
  15 #include "beam.hh"
  16 #include "directional-element-interface.hh"
  17 #include "group-interface.hh"
  18 #include "slur.hh"
  19 #include "note-column.hh"
  20 #include "output-def.hh"
  21 #include "pitch.hh"
  22 #include "spanner.hh"
  23 #include "staff-symbol-referencer.hh"
  24 #include "staff-symbol.hh"
  25 #include "stem.hh"
  26 #include "warn.hh"
  27 #include "paper-column.hh"
  28 #include "accidental-interface.hh"
  29
  30 /*
  31   TODO:
  32
  33   - curve around flag for y coordinate
  34
  35   - this file is a mess, clean it up
  36
  37   - short-cut: try a smaller region first.
  38
  39   - handle non-visible stems better.
  40
  41   - try to prune number of scoring criteria
  42
  43   - take encompass-objects more into account when determining
  44   slur shape
  45
  46   - calculate encompass scoring directly after determining slur shape.
  47
  48   - optimize.
  49 */
  50 struct Slur_score_state;
  51
  52 Slur_score_state::Slur_score_state ()
  53 {
  54   musical_dy_ = 0.0;
  55   valid_ = false;
  56   edge_has_beams_ = false;
  57   has_same_beam_ = false;
  58   is_broken_ = false;
  59   dir_ = CENTER;
  60   slur_ = 0;
  61   common_[X_AXIS] = 0;
  62   common_[Y_AXIS] = 0;
  63 }
  64
  65 Slur_score_state::~Slur_score_state ()
  66 {
  67   junk_pointers (configurations_);
  68 }
  69
  70 Real
  71 get_detail (SCM alist, SCM sym)
  72 {
  73   SCM entry = scm_assq (sym, alist);
  74   return robust_scm2double (scm_is_pair (entry)
  75                             ? scm_cdr (entry)
  76                             : SCM_EOL,
  77                             0.0);
  78 }
  79
  80 void
  81 Slur_score_parameters::fill (Grob *me)
  82 {
  83   SCM details = me->get_property ("slur-details");
  84
  85   region_size_
  86     = (int) get_detail (details, ly_symbol2scm ("region-size"));
  87   head_encompass_penalty_
  88     = get_detail (details, ly_symbol2scm ("head-encompass-penalty"));
  89   stem_encompass_penalty_
  90     = get_detail (details, ly_symbol2scm ("stem-encompass-penalty"));
  91   closeness_factor_
  92     = get_detail (details, ly_symbol2scm ("closeness-factor"));
  93   edge_attraction_factor_
  94     = get_detail (details, ly_symbol2scm ("edge-attraction-factor"));
  95   same_slope_penalty_
  96     = get_detail (details, ly_symbol2scm ("same-slope-penalty"));
  97   steeper_slope_factor_
  98     = get_detail (details, ly_symbol2scm ("steeper-slope-factor"));
  99   non_horizontal_penalty_
 100     = get_detail (details, ly_symbol2scm ("non-horizontal-penalty"));
 101   max_slope_
 102     = get_detail (details, ly_symbol2scm ("max-slope"));
 103   max_slope_factor_
 104     = get_detail (details, ly_symbol2scm ("max-slope-factor"));
 105   free_head_distance_
 106     = get_detail (details, ly_symbol2scm ("free-head-distance"));
 107   absolute_closeness_measure_
 108     = get_detail (details, ly_symbol2scm ("absolute-closeness-measure"));
 109   extra_object_collision_
 110     = get_detail (details, ly_symbol2scm ("extra-object-collision"));
 111   accidental_collision_
 112     = get_detail (details, ly_symbol2scm ("accidental-collision"));
 113   extra_encompass_free_distance_
 114     = get_detail (details, ly_symbol2scm ("extra-encompass-free-distance"));
 115   head_slur_distance_factor_
 116     = get_detail (details, ly_symbol2scm ("head-slur-distance-factor"));
 117   head_slur_distance_max_ratio_
 118     = get_detail (details, ly_symbol2scm ("head-slur-distance-max-ratio"));
 119   free_slur_distance_
 120     = get_detail (details, ly_symbol2scm ("free-slur-distance"));
 121   edge_slope_exponent_
 122     = get_detail (details, ly_symbol2scm ("edge-slope-exponent"));
 123 }
 124
 125 Real
 126 broken_trend_y (Slur_score_state const &state, Direction hdir)
 127 {
 128   /* A broken slur should maintain the same vertical trend
 129      the unbroken slur would have had.  */
 130   Real by = 0.0;
 131   if (Spanner *mother = dynamic_cast<Spanner *> (state.slur_->original_))
 132     {
 133       int k = broken_spanner_index (state.slur_);
 134       int j = k + hdir;
 135       if (j < 0 || j >= mother->broken_intos_.size ())
 136         return by;
 137
 138       Grob *neighbor = mother->broken_intos_[j];
 139       Spanner *common_mother
 140         = dynamic_cast<Spanner *> (state.common_[Y_AXIS]->original_);
 141       int common_k
 142         = broken_spanner_index (dynamic_cast<Spanner *> (state.common_[Y_AXIS]));
 143       int common_j = common_k + hdir;
 144
 145       if (common_j < 0 || common_j >= common_mother->broken_intos_.size ())
 146         return by;
 147
 148       Grob *common_next_system = common_mother->broken_intos_[common_j];
 149
 150       SCM last_point = scm_car (scm_last_pair (neighbor->get_property ("control-points")));
 151
 152       return scm_to_double (scm_cdr (last_point))
 153         + neighbor->relative_coordinate (common_next_system, Y_AXIS);
 154     }
 155   return by;
 156 }
 157
 158 /*
 159   copy slur dir forwards across line break.
 160 */
 161 void
 162 Slur_score_state::set_next_direction ()
 163 {
 164   if (extremes_[RIGHT].note_column_)
 165     return;
 166
 167   if (Spanner *mother = dynamic_cast<Spanner *> (slur_->original_))
 168     {
 169       int k = broken_spanner_index (slur_);
 170       int j = k + 1;
 171       if (j < 0 || j >= mother->broken_intos_.size ())
 172         return;
 173
 174       Grob *neighbor = mother->broken_intos_[j];
 175       set_grob_direction (neighbor, dir_);
 176     }
 177 }
 178
 179 Encompass_info
 180 Slur_score_state::get_encompass_info (Grob *col) const
 181 {
 182   Grob *stem = unsmob_grob (col->get_property ("stem"));
 183   Encompass_info ei;
 184
 185   if (!stem)
 186     {
 187       programming_error ("No stem for note column?");
 188       ei.x_ = col->relative_coordinate (common_[X_AXIS], X_AXIS);
 189       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS],
 190                                          Y_AXIS)[dir_];
 191       return ei;
 192     }
 193   Direction stem_dir = get_grob_direction (stem);
 194
 195   if (Grob *head = Note_column::first_head (col))
 196     ei.x_ = head->extent (common_[X_AXIS], X_AXIS).center ();
 197   else
 198     ei.x_ = col->extent (common_[X_AXIS], X_AXIS).center ();
 199
 200   Grob *h = Stem::extremal_heads (stem)[Direction (dir_)];
 201   if (!h)
 202     {
 203       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 204       return ei;
 205     }
 206
 207   ei.head_ = h->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 208
 209   if ((stem_dir == dir_)
 210       && !stem->extent (stem, Y_AXIS).is_empty ())
 211     {
 212       ei.stem_ = stem->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 213       if (Grob *b = Stem::get_beam (stem))
 214         ei.stem_ += stem_dir * 0.5 * Beam::get_thickness (b);
 215
 216       Interval x = stem->extent (common_[X_AXIS], X_AXIS);
 217       ei.x_ = x.is_empty ()
 218         ? stem->relative_coordinate (common_[X_AXIS], X_AXIS)
 219         : x.center ();
 220     }
 221   else
 222     ei.stem_ = ei.head_;
 223
 224   return ei;
 225 }
 226
 227 Drul_array<Bound_info>
 228 Slur_score_state::get_bound_info () const
 229 {
 230   Drul_array<Bound_info> extremes;
 231
 232   Direction d = LEFT;
 233   Direction dir = dir_;
 234
 235   do
 236     {
 237       extremes[d].bound_ = slur_->get_bound (d);
 238       if (Note_column::has_interface (extremes[d].bound_))
 239         {
 240           extremes[d].note_column_ = extremes[d].bound_;
 241           extremes[d].stem_ = Note_column::get_stem (extremes[d].note_column_);
 242           extremes[d].stem_dir_ = get_grob_direction (extremes[d].stem_);
 243           extremes[d].stem_extent_[X_AXIS]
 244             = extremes[d].stem_->extent (common_[X_AXIS], X_AXIS);
 245           extremes[d].stem_extent_[Y_AXIS]
 246             = extremes[d].stem_->extent (common_[Y_AXIS], Y_AXIS);
 247           extremes[d].slur_head_
 248             = Stem::extremal_heads (extremes[d].stem_)[dir];
 249           if (!extremes[d].slur_head_
 250               && Note_column::has_rests (extremes[d].bound_))
 251             {
 252               extremes[d].slur_head_ = Note_column::get_rest (extremes[d].bound_);
 253             }
 254
 255           if (extremes[d].slur_head_)
 256             extremes[d].slur_head_extent_
 257               = extremes[d].slur_head_->extent (common_[X_AXIS], X_AXIS);
 258
 259           extremes[d].staff_ = Staff_symbol_referencer
 260             ::get_staff_symbol (extremes[d].stem_);
 261           extremes[d].staff_space_ = Staff_symbol_referencer
 262             ::staff_space (extremes[d].stem_);
 263         }
 264     }
 265   while (flip (&d) != LEFT);
 266
 267   return extremes;
 268 }
 269
 270 void
 271 Slur_score_state::fill (Grob *me)
 272 {
 273   slur_ = dynamic_cast<Spanner *> (me);
 274   columns_
 275     = extract_grob_array (me, ly_symbol2scm ("note-columns"));
 276
 277   if (columns_.is_empty ())
 278     {
 279       me->suicide ();
 280       return;
 281     }
 282
 283   staff_space_ = Staff_symbol_referencer::staff_space (me);
 284   Real lt = me->get_layout ()->get_dimension (ly_symbol2scm ("linethickness"));
 285   thickness_ = robust_scm2double (me->get_property ("thickness"), 1.0) * lt;
 286
 287   dir_ = get_grob_direction (me);
 288   parameters_.fill (me);
 289
 290   SCM eltlist = me->get_property ("note-columns");
 291   SCM extra_list = me->get_property ("encompass-objects");
 292   Spanner *sp = dynamic_cast<Spanner *> (me);
 293
 294   for (int i = X_AXIS; i < NO_AXES; i++)
 295     {
 296       Axis a = (Axis)i;
 297       common_[a] = common_refpoint_of_list (eltlist, me, a);
 298       common_[a] = common_refpoint_of_list (extra_list, common_[a], a);
 299
 300       Direction d = LEFT;
 301       do
 302         {
 303           /*
 304             If bound is not in note-columns, we don't want to know about
 305             its Y-position
 306           */
 307           if (a != Y_AXIS)
 308             common_[a] = common_[a]->common_refpoint (sp->get_bound (d), a);
 309         }
 310       while (flip (&d) != LEFT);
 311     }
 312
 313   extremes_ = get_bound_info ();
 314   is_broken_ = (!extremes_[LEFT].note_column_
 315                 || !extremes_[RIGHT].note_column_);
 316
 317   has_same_beam_
 318     = (extremes_[LEFT].stem_ && extremes_[RIGHT].stem_
 319        && Stem::get_beam (extremes_[LEFT].stem_) == Stem::get_beam (extremes_[RIGHT].stem_));
 320
 321   base_attachments_ = get_base_attachments ();
 322
 323   Drul_array<Real> end_ys
 324     = get_y_attachment_range ();
 325
 326   configurations_ = enumerate_attachments (end_ys);
 327   for (int i = 0; i < columns_.size (); i++)
 328     encompass_infos_.push (get_encompass_info (columns_[i]));
 329
 330   extra_encompass_infos_ = get_extra_encompass_infos ();
 331   valid_ = true;
 332
 333   musical_dy_ = 0.0;
 334   Direction d = LEFT;
 335   do
 336     {
 337       if (!is_broken_)
 338         musical_dy_ += d
 339           * extremes_[d].slur_head_->relative_coordinate (common_[Y_AXIS], Y_AXIS);
 340     }
 341   while (flip (&d) != LEFT);
 342
 343   edge_has_beams_
 344     = (extremes_[LEFT].stem_ && Stem::get_beam (extremes_[LEFT].stem_))
 345     || (extremes_[RIGHT].stem_ && Stem::get_beam (extremes_[RIGHT].stem_));
 346
 347   set_next_direction ();
 348
 349   if (is_broken_)
 350     musical_dy_ = 0.0;
 351 }
 352
 353 void
 354 set_slur_control_points (Grob *me)
 355 {
 356   Slur_score_state state;
 357   state.fill (me);
 358
 359   if (!state.valid_)
 360     return;
 361
 362   state.generate_curves ();
 363
 364   SCM end_ys = me->get_property ("positions");
 365   Bezier best;
 366
 367   if (is_number_pair (end_ys))
 368     {
 369       best = state.configurations_[state.get_closest_index (end_ys)]->curve_;
 370     }
 371   else
 372     {
 373       best = state.get_best_curve ();
 374     }
 375
 376   SCM controls = SCM_EOL;
 377   for (int i = 4; i--;)
 378     {
 379       Offset o = best.control_[i]
 380         - Offset (me->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 381                   me->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 382       controls = scm_cons (ly_offset2scm (o), controls);
 383     }
 384   me->set_property ("control-points", controls);
 385 }
 386
 387 Bezier
 388 Slur_score_state::get_best_curve ()
 389 {
 390   for (int i = 0; i < configurations_.size (); i++)
 391     {
 392       configurations_[i]->score (*this);
 393     }
 394
 395   Real opt = 1e6;
 396   int opt_idx = -1;
 397   for (int i = 0; i < configurations_.size (); i++)
 398     {
 399       if (configurations_[i]->score_ < opt)
 400         {
 401           opt = configurations_[i]->score_;
 402           opt_idx = i;
 403         }
 404     }
 405
 406 #if DEBUG_SLUR_SCORING
 407   SCM inspect_quants = slur_->get_property ("inspect-quants");
 408   if (to_boolean (slur_->get_layout ()
 409                   ->lookup_variable (ly_symbol2scm ("debug-slur-scoring")))
 410       && scm_is_pair (inspect_quants))
 411     opt_idx = get_closest_index (inspect_quants);
 412
 413   configurations_[opt_idx]->score_card_ += to_string ("=%.2f", opt);
 414   configurations_[opt_idx]->score_card_ += to_string ("i%d", opt_idx);
 415
 416   // debug quanting
 417   slur_->set_property ("quant-score",
 418                        scm_makfrom0str (configurations_[opt_idx]->score_card_.to_str0 ()));
 419
 420 #endif
 421
 422   return configurations_[opt_idx]->curve_;
 423 }
 424
 425 int
 426 Slur_score_state::get_closest_index (SCM inspect_quants) const
 427 {
 428   Drul_array<Real> ins = ly_scm2interval (inspect_quants);
 429
 430   int opt_idx = -1;
 431   Real mindist = 1e6;
 432   for (int i = 0; i < configurations_.size (); i++)
 433     {
 434       Real d = fabs (configurations_[i]->attachment_[LEFT][Y_AXIS] - ins[LEFT])
 435         + fabs (configurations_[i]->attachment_[RIGHT][Y_AXIS] - ins[RIGHT]);
 436       if (d < mindist)
 437         {
 438           opt_idx = i;
 439           mindist = d;
 440         }
 441     }
 442   if (mindist > 1e5)
 443     programming_error ("Could not find quant.");
 444   return opt_idx;
 445 }
 446
 447 /*
 448   TODO: should analyse encompasses to determine sensible region, and
 449   should limit slopes available.
 450 */
 451
 452 Drul_array<Real>
 453 Slur_score_state::get_y_attachment_range () const
 454 {
 455   Drul_array<Real> end_ys;
 456   Direction d = LEFT;
 457   do
 458     {
 459       if (extremes_[d].note_column_)
 460         {
 461           end_ys[d] = dir_
 462             * ((dir_ * (base_attachments_[d][Y_AXIS] + parameters_.region_size_ * dir_))
 463                >? (dir_ * (dir_ + extremes_[d].note_column_->extent (common_[Y_AXIS],
 464                                                                      Y_AXIS)[dir_]))
 465                >? (dir_ * base_attachments_[-d][Y_AXIS]));
 466         }
 467       else
 468         end_ys[d] = base_attachments_[d][Y_AXIS] + parameters_.region_size_ * dir_;
 469     }
 470   while (flip (&d) != LEFT);
 471
 472   return end_ys;
 473 }
 474
 475 bool
 476 spanner_less (Spanner *s1, Spanner *s2)
 477 {
 478   Slice b1, b2;
 479   Direction d = LEFT;
 480   do
 481     {
 482       b1[d] = s1->get_bound (d)->get_column ()->rank_;
 483       b2[d] = s2->get_bound (d)->get_column ()->rank_;
 484     }
 485   while (flip (&d) != LEFT);
 486
 487   return b2[LEFT] <= b1[LEFT] && b2[RIGHT] >= b1[RIGHT]
 488     && (b2[LEFT] != b1[LEFT] || b2[RIGHT] != b1[RIGHT]);
 489 }
 490
 491 Drul_array<Offset>
 492 Slur_score_state::get_base_attachments () const
 493 {
 494   Drul_array<Offset> base_attachment;
 495   Direction d = LEFT;
 496   do
 497     {
 498       Grob *stem = extremes_[d].stem_;
 499       Grob *head = extremes_[d].slur_head_;
 500
 501       Real x = 0.0;
 502       Real y = 0.0;
 503       if (extremes_[d].note_column_)
 504         {
 505
 506           /*
 507             fixme: X coord should also be set in this case.
 508           */
 509           if (stem
 510               && extremes_[d].stem_dir_ == dir_
 511               && Stem::get_beaming (stem, -d)
 512               && (!spanner_less (slur_, Stem::get_beam (stem))
 513                   || has_same_beam_))
 514             y = extremes_[d].stem_extent_[Y_AXIS][dir_];
 515           else if (head)
 516             y = head->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 517           y += dir_ * 0.5 * staff_space_;
 518
 519           y = move_away_from_staffline (y, head);
 520
 521           Grob *fh = Note_column::first_head (extremes_[d].note_column_);
 522           x
 523             = (fh ? fh->extent (common_[X_AXIS], X_AXIS)
 524                : extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS))
 525             .linear_combination (CENTER);
 526         }
 527       base_attachment[d] = Offset (x, y);
 528     }
 529   while (flip (&d) != LEFT);
 530
 531   do
 532     {
 533       if (!extremes_[d].note_column_)
 534         {
 535           Real x, y;
 536           if (d == RIGHT)
 537             {
 538               x = extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS)[d];
 539             }
 540           else
 541             {
 542               x = slur_->get_broken_left_end_align ();
 543             }
 544           Grob *col = (d == LEFT) ? columns_[0] : columns_.top ();
 545
 546           if (extremes_[-d].bound_ != col)
 547             {
 548               y = robust_relative_extent (col, common_[Y_AXIS], Y_AXIS)[dir_];
 549               y += dir_ * 0.5 * staff_space_;
 550
 551               if (get_grob_direction (col) == dir_
 552                   && Note_column::get_stem (col)
 553                   && !Stem::is_invisible (Note_column::get_stem (col)))
 554                 y -= dir_ * 1.5 * staff_space_;
 555             }
 556           else
 557             y = base_attachment[-d][Y_AXIS];
 558
 559           y = move_away_from_staffline (y, col);
 560
 561           base_attachment[d] = Offset (x, y);
 562         }
 563     }
 564   while (flip (&d) != LEFT);
 565
 566   return base_attachment;
 567 }
 568
 569 Real
 570 Slur_score_state::move_away_from_staffline (Real y,
 571                                             Grob *on_staff) const
 572 {
 573   Real pos
 574     = (y - Staff_symbol_referencer::get_staff_symbol (on_staff)->relative_coordinate (common_[Y_AXIS],
 575                                                                                       Y_AXIS))
 576     * 2.0 / staff_space_;
 577
 578   if (fabs (pos - my_round (pos)) < 0.2
 579       && Staff_symbol_referencer::on_staffline (on_staff, (int) rint (pos))
 580       && Staff_symbol_referencer::line_count (on_staff) - 1 >= rint (pos))
 581     y += 1.5 * staff_space_ * dir_ / 10;
 582
 583   return y;
 584 }
 585
 586 void
 587 Slur_score_state::generate_curves () const
 588 {
 589   Real r_0 = robust_scm2double (slur_->get_property ("ratio"), 0.33);
 590   Real h_inf = staff_space_ * scm_to_double (slur_->get_property ("height-limit"));
 591   for (int i = 0; i < configurations_.size (); i++)
 592     configurations_[i]->generate_curve (*this, r_0, h_inf);
 593 }
 594
 595 Link_array<Slur_configuration>
 596 Slur_score_state::enumerate_attachments (Drul_array<Real> end_ys) const
 597 {
 598   /*ugh.   */
 599   Link_array<Slur_configuration> scores;
 600
 601   Drul_array<Offset> os;
 602   os[LEFT] = base_attachments_[LEFT];
 603   Real minimum_length = staff_space_
 604     * robust_scm2double (slur_->get_property ("minimum-length"), 2.0);
 605
 606   for (int i = 0; dir_ * os[LEFT][Y_AXIS] <= dir_ * end_ys[LEFT]; i++)
 607     {
 608       os[RIGHT] = base_attachments_[RIGHT];
 609       for (int j = 0; dir_ * os[RIGHT][Y_AXIS] <= dir_ * end_ys[RIGHT]; j++)
 610         {
 611           Slur_configuration s;
 612           Direction d = LEFT;
 613           Drul_array<bool> attach_to_stem (false, false);
 614           do
 615             {
 616               os[d][X_AXIS] = base_attachments_[d][X_AXIS];
 617               if (extremes_[d].stem_
 618                   && !Stem::is_invisible (extremes_[d].stem_)
 619                   && extremes_[d].stem_dir_ == dir_)
 620                 {
 621                   Interval stem_y = extremes_[d].stem_extent_[Y_AXIS];
 622                   stem_y.widen (0.25 * staff_space_);
 623                   if (stem_y.contains (os[d][Y_AXIS]))
 624                     {
 625                       os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS][-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                     os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS].center ();
 634                 }
 635             }
 636           while (flip (&d) != LEFT);
 637
 638           Offset dz;
 639           dz = os[RIGHT] - os[LEFT];
 640           if (dz[X_AXIS] < minimum_length
 641               || fabs (dz[Y_AXIS] / dz[X_AXIS]) > parameters_.max_slope_)
 642             {
 643               do
 644                 {
 645                   if (extremes_[d].slur_head_)
 646                     {
 647                       os[d][X_AXIS] = extremes_[d].slur_head_extent_.center ();
 648                       attach_to_stem[d] = false;
 649                     }
 650                 }
 651               while (flip (&d) != LEFT);
 652             }
 653
 654           dz = os[RIGHT] - os[LEFT];
 655           do
 656             {
 657               if (extremes_[d].slur_head_
 658                   && !attach_to_stem[d])
 659                 {
 660                   /* Horizontally move tilted slurs a little.  Move
 661                      more for bigger tilts.
 662
 663                      TODO: parameter */
 664                   os[d][X_AXIS]
 665                     -= dir_ * extremes_[d].slur_head_extent_.length ()
 666                     * sin (dz.arg ()) / 3;
 667                 }
 668             }
 669           while (flip (&d) != LEFT);
 670
 671           s.attachment_ = os;
 672           s.index_ = scores.size ();
 673
 674           scores.push (new Slur_configuration (s));
 675
 676           os[RIGHT][Y_AXIS] += dir_ * staff_space_ / 2;
 677         }
 678
 679       os[LEFT][Y_AXIS] += dir_ * staff_space_ / 2;
 680     }
 681
 682   assert (scores.size () > 0);
 683   return scores;
 684 }
 685
 686 Array<Extra_collision_info>
 687 Slur_score_state::get_extra_encompass_infos () const
 688 {
 689   Link_array<Grob> encompasses
 690     = extract_grob_array (slur_, ly_symbol2scm ("encompass-objects"));
 691   Array<Extra_collision_info> collision_infos;
 692   for (int i = encompasses.size (); i--;)
 693     {
 694       if (Slur::has_interface (encompasses[i]))
 695         {
 696           Spanner *small_slur = dynamic_cast<Spanner *> (encompasses[i]);
 697           Bezier b = Slur::get_curve (small_slur);
 698
 699           Offset relative (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 700                            small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 701
 702           for (int k = 0; k < 3; k++)
 703             {
 704               Direction hdir = Direction (k / 2 - 1);
 705
 706               /*
 707                 Only take bound into account if small slur starts
 708                 together with big slur.
 709               */
 710               if (hdir && small_slur->get_bound (hdir) != slur_->get_bound (hdir))
 711                 continue;
 712
 713               Offset z = b.curve_point (k / 2.0);
 714               z += relative;
 715
 716               Interval yext;
 717               yext.set_full ();
 718               yext[dir_] = z[Y_AXIS] + dir_ * thickness_ * 1.0;
 719
 720               Interval xext (-1, 1);
 721               xext = xext * (thickness_ * 2) + z[X_AXIS];
 722               Extra_collision_info info (small_slur,
 723                                          k - 1.0,
 724                                          xext,
 725                                          yext,
 726                                          parameters_.extra_object_collision_);
 727               collision_infos.push (info);
 728             }
 729         }
 730       else
 731         {
 732           Grob *g = encompasses [i];
 733           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 734           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 735
 736           Real xp = 0.0;
 737           Real penalty = parameters_.extra_object_collision_;
 738           if (Accidental_interface::has_interface (g))
 739             {
 740               penalty = parameters_.accidental_collision_;
 741               /* Begin copy accidental.cc */
 742               bool parens = false;
 743               if (to_boolean (g->get_property ("cautionary")))
 744                 {
 745                   SCM cstyle = g->get_property ("cautionary-style");
 746                   parens = ly_c_equal_p (cstyle, ly_symbol2scm ("parentheses"));
 747                 }
 748
 749               SCM accs = g->get_property ("accidentals");
 750               SCM scm_style = g->get_property ("style");
 751               if (!scm_is_symbol (scm_style)
 752                   && !parens
 753                   && scm_ilength (accs) == 1)
 754                 {
 755                   /* End copy accidental.cc */
 756                   switch (scm_to_int (scm_car (accs)))
 757                     {
 758                     case FLAT:
 759                     case DOUBLE_FLAT:
 760                       xp = LEFT;
 761                       break;
 762                     case SHARP:
 763                       xp = 0.5 * dir_;
 764                       break;
 765                     case NATURAL:
 766                       xp = -dir_;
 767                       break;
 768                     }
 769                 }
 770             }
 771
 772           ye.widen (thickness_ * 0.5);
 773           xe.widen (thickness_ * 1.0);
 774           Extra_collision_info info (g, xp, xe, ye, penalty);
 775           collision_infos.push (info);
 776         }
 777     }
 778
 779   return collision_infos;
 780 }
 781