lily/slur-scoring.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1996--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5   Jan Nieuwenhuizen <janneke@gnu.org>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "slur-scoring.hh"
  22
  23 #include <queue>
  24
  25 #include "axis-group-interface.hh"
  26 #include "accidental-interface.hh"
  27 #include "beam.hh"
  28 #include "clef.hh"
  29 #include "directional-element-interface.hh"
  30 #include "dots.hh"
  31 #include "libc-extension.hh"
  32 #include "main.hh"
  33 #include "misc.hh"
  34 #include "note-column.hh"
  35 #include "output-def.hh"
  36 #include "paper-column.hh"
  37 #include "pitch.hh"
  38 #include "pointer-group-interface.hh"
  39 #include "slur-configuration.hh"
  40 #include "slur.hh"
  41 #include "spanner.hh"
  42 #include "staff-symbol-referencer.hh"
  43 #include "staff-symbol.hh"
  44 #include "stem.hh"
  45 #include "warn.hh"
  46
  47 /*
  48   TODO:
  49
  50   - curve around flag for y coordinate
  51
  52   - short-cut: try a smaller region first.
  53
  54   - handle non-visible stems better.
  55
  56   - try to prune number of scoring criteria
  57
  58   - take encompass-objects more into account when determining
  59   slur shape
  60
  61   - calculate encompass scoring directly after determining slur shape.
  62
  63   - optimize.
  64 */
  65 struct Slur_score_state;
  66
  67 Slur_score_state::Slur_score_state ()
  68 {
  69   musical_dy_ = 0.0;
  70   valid_ = false;
  71   edge_has_beams_ = false;
  72   has_same_beam_ = false;
  73   is_broken_ = false;
  74   dir_ = CENTER;
  75   slur_ = 0;
  76   common_[X_AXIS] = 0;
  77   common_[Y_AXIS] = 0;
  78 }
  79
  80 Slur_score_state::~Slur_score_state ()
  81 {
  82   junk_pointers (configurations_);
  83 }
  84
  85 /*
  86   If a slur is broken across a line break, the direction
  87   of the post-break slur must be the same as the pre-break
  88   slur.
  89 */
  90 Direction
  91 Slur_score_state::slur_direction () const
  92 {
  93   Grob *left_neighbor = slur_->broken_neighbor (LEFT);
  94
  95   if (left_neighbor && left_neighbor->is_live ())
  96     return get_grob_direction (left_neighbor);
  97
  98   Direction dir = get_grob_direction (slur_);
  99
 100   if (Grob *right_neighbor = slur_->broken_neighbor (RIGHT))
 101     set_grob_direction (right_neighbor, dir);
 102
 103   return dir;
 104 }
 105
 106 Encompass_info
 107 Slur_score_state::get_encompass_info (Grob *col) const
 108 {
 109   Grob *stem = unsmob<Grob> (col->get_object ("stem"));
 110   Encompass_info ei;
 111
 112   if (!stem)
 113     {
 114       programming_error ("no stem for note column");
 115       ei.x_ = col->relative_coordinate (common_[X_AXIS], X_AXIS);
 116       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS],
 117                                          Y_AXIS)[dir_];
 118       return ei;
 119     }
 120   Direction stem_dir = get_grob_direction (stem);
 121
 122   if (Grob *head = Note_column::first_head (col))
 123     ei.x_ = head->extent (common_[X_AXIS], X_AXIS).center ();
 124   else
 125     ei.x_ = col->extent (common_[X_AXIS], X_AXIS).center ();
 126
 127   Grob *h = Stem::extremal_heads (stem)[Direction (dir_)];
 128   if (!h)
 129     {
 130       ei.head_ = ei.stem_ = col->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 131       return ei;
 132     }
 133
 134   ei.head_ = h->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 135
 136   if ((stem_dir == dir_)
 137       && !stem->extent (stem, Y_AXIS).is_empty ())
 138     {
 139       ei.stem_ = stem->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 140       if (Grob *b = Stem::get_beam (stem))
 141         ei.stem_ += stem_dir * 0.5 * Beam::get_beam_thickness (b);
 142
 143       Interval x = stem->extent (common_[X_AXIS], X_AXIS);
 144       ei.x_ = x.is_empty ()
 145               ? stem->relative_coordinate (common_[X_AXIS], X_AXIS)
 146               : x.center ();
 147     }
 148   else
 149     ei.stem_ = ei.head_;
 150
 151   return ei;
 152 }
 153
 154 Drul_array<Bound_info>
 155 Slur_score_state::get_bound_info () const
 156 {
 157   Drul_array<Bound_info> extremes;
 158
 159   Direction dir = dir_;
 160
 161   for (LEFT_and_RIGHT (d))
 162     {
 163       extremes[d].bound_ = slur_->get_bound (d);
 164       if (has_interface<Note_column> (extremes[d].bound_))
 165         {
 166           extremes[d].note_column_ = extremes[d].bound_;
 167           extremes[d].stem_ = Note_column::get_stem (extremes[d].note_column_);
 168           extremes[d].flag_ = Note_column::get_flag (extremes[d].note_column_);
 169
 170           if (extremes[d].stem_)
 171             {
 172               extremes[d].stem_dir_ = get_grob_direction (extremes[d].stem_);
 173
 174               for (int a = X_AXIS; a < NO_AXES; a++)
 175                 {
 176                   Axis ax = Axis (a);
 177                   Interval s = extremes[d].stem_->extent (common_[ax], ax);
 178                   if (extremes[d].flag_)
 179                     s.unite (extremes[d].flag_->extent (common_[ax], ax));
 180                   if (s.is_empty ())
 181                     {
 182                       /*
 183                         do not issue warning. This happens for rests and
 184                         whole notes.
 185                       */
 186                       s = Interval (0, 0)
 187                           + extremes[d].stem_->relative_coordinate (common_[ax], ax);
 188                     }
 189                   extremes[d].stem_extent_[ax] = s;
 190                 }
 191
 192               extremes[d].slur_head_
 193                 = Stem::extremal_heads (extremes[d].stem_)[dir];
 194               if (!extremes[d].slur_head_
 195                   && Note_column::has_rests (extremes[d].bound_))
 196                 extremes[d].slur_head_ = Note_column::get_rest (extremes[d].bound_);
 197               extremes[d].staff_ = Staff_symbol_referencer
 198                                    ::get_staff_symbol (extremes[d].stem_);
 199               extremes[d].staff_space_ = Staff_symbol_referencer
 200                                          ::staff_space (extremes[d].stem_);
 201             }
 202
 203           if (extremes[d].slur_head_)
 204             extremes[d].slur_head_x_extent_
 205               = extremes[d].slur_head_->extent (common_[X_AXIS], X_AXIS);
 206
 207         }
 208     }
 209
 210   return extremes;
 211 }
 212
 213 void
 214 Slur_score_state::fill (Grob *me)
 215 {
 216   slur_ = dynamic_cast<Spanner *> (me);
 217   columns_
 218     = internal_extract_grob_array (me, ly_symbol2scm ("note-columns"));
 219
 220   if (columns_.empty ())
 221     {
 222       me->suicide ();
 223       return;
 224     }
 225
 226   Slur::replace_breakable_encompass_objects (me);
 227   staff_space_ = Staff_symbol_referencer::staff_space (me);
 228   line_thickness_ = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 229   thickness_ = robust_scm2double (me->get_property ("thickness"), 1.0) * line_thickness_;
 230
 231   dir_ = slur_direction ();
 232   parameters_.fill (me);
 233
 234   extract_grob_set (me, "note-columns", columns);
 235   extract_grob_set (me, "encompass-objects", extra_objects);
 236
 237   Spanner *sp = dynamic_cast<Spanner *> (me);
 238
 239   for (int i = X_AXIS; i < NO_AXES; i++)
 240     {
 241       Axis a = (Axis)i;
 242       common_[a] = common_refpoint_of_array (columns, me, a);
 243       common_[a] = common_refpoint_of_array (extra_objects, common_[a], a);
 244
 245       for (LEFT_and_RIGHT (d))
 246         {
 247           /*
 248             If bound is not in note-columns, we don't want to know about
 249             its Y-position
 250           */
 251           if (a != Y_AXIS)
 252             common_[a] = common_[a]->common_refpoint (sp->get_bound (d), a);
 253         }
 254     }
 255
 256   extremes_ = get_bound_info ();
 257   is_broken_ = (!extremes_[LEFT].note_column_
 258                 || !extremes_[RIGHT].note_column_);
 259
 260   has_same_beam_
 261     = (extremes_[LEFT].stem_ && extremes_[RIGHT].stem_
 262        && Stem::get_beam (extremes_[LEFT].stem_) == Stem::get_beam (extremes_[RIGHT].stem_));
 263
 264   base_attachments_ = get_base_attachments ();
 265
 266   Drul_array<Real> end_ys
 267     = get_y_attachment_range ();
 268
 269   extra_encompass_infos_ = get_extra_encompass_infos ();
 270
 271   Interval additional_ys (0.0, 0.0);
 272
 273   for (vsize i = 0; i < extra_encompass_infos_.size (); i++)
 274     {
 275       if (extra_encompass_infos_[i].extents_[X_AXIS].is_empty ())
 276         continue;
 277
 278       Real y_place = linear_interpolate (extra_encompass_infos_[i].extents_[X_AXIS].center (),
 279                                          base_attachments_[RIGHT][X_AXIS],
 280                                          base_attachments_[LEFT][X_AXIS],
 281                                          end_ys[RIGHT],
 282                                          end_ys[LEFT]);
 283       Real encompass_place = extra_encompass_infos_[i].extents_[Y_AXIS][dir_];
 284       if (scm_is_eq (extra_encompass_infos_[i].type_,
 285                      ly_symbol2scm ("inside"))
 286           && minmax (dir_, encompass_place, y_place) == encompass_place
 287           && (!extra_encompass_infos_[i].grob_->internal_has_interface (ly_symbol2scm ("key-signature-interface"))
 288               && !has_interface<Clef> (extra_encompass_infos_[i].grob_)
 289               && !extra_encompass_infos_[i].grob_->internal_has_interface (ly_symbol2scm ("time-signature-interface"))))
 290         {
 291           for (LEFT_and_RIGHT (d))
 292             additional_ys[d] = minmax (dir_,
 293                                        additional_ys[d],
 294                                        (dir_
 295                                         * (parameters_.encompass_object_range_overshoot_
 296                                            + (y_place - encompass_place)
 297                                            * (normalize (extra_encompass_infos_[i].extents_[X_AXIS].center (),
 298                                                          base_attachments_[RIGHT][X_AXIS],
 299                                                          base_attachments_[LEFT][X_AXIS])
 300                                               + (dir_ == LEFT ? 0 : -1)))));
 301         }
 302     }
 303
 304   for (LEFT_and_RIGHT (d))
 305     end_ys[d] += additional_ys[d];
 306
 307   configurations_ = enumerate_attachments (end_ys);
 308   for (vsize i = 0; i < columns_.size (); i++)
 309     encompass_infos_.push_back (get_encompass_info (columns_[i]));
 310
 311   valid_ = true;
 312
 313   musical_dy_ = 0.0;
 314   for (LEFT_and_RIGHT (d))
 315     {
 316       if (!is_broken_
 317           && extremes_[d].slur_head_)
 318         musical_dy_ += d
 319                        * extremes_[d].slur_head_->relative_coordinate (common_[Y_AXIS], Y_AXIS);
 320     }
 321
 322   edge_has_beams_
 323     = (extremes_[LEFT].stem_ && Stem::get_beam (extremes_[LEFT].stem_))
 324       || (extremes_[RIGHT].stem_ && Stem::get_beam (extremes_[RIGHT].stem_));
 325
 326   if (is_broken_)
 327     musical_dy_ = 0.0;
 328 }
 329
 330 MAKE_SCHEME_CALLBACK (Slur, calc_control_points, 1)
 331 SCM
 332 Slur::calc_control_points (SCM smob)
 333 {
 334   Spanner *me = unsmob<Spanner> (smob);
 335
 336   Slur_score_state state;
 337   state.fill (me);
 338
 339   if (!state.valid_)
 340     return SCM_EOL;
 341
 342   state.generate_curves ();
 343
 344   SCM end_ys = me->get_property ("positions");
 345   SCM inspect_quants = me->get_property ("inspect-quants");
 346   bool debug_slurs = to_boolean (me->layout ()
 347                                  ->lookup_variable (ly_symbol2scm ("debug-slur-scoring")));
 348
 349   if (is_number_pair (inspect_quants))
 350     {
 351       debug_slurs = true;
 352       end_ys = inspect_quants;
 353     }
 354
 355   Slur_configuration *best = NULL;
 356   if (is_number_pair (end_ys))
 357     best = state.get_forced_configuration (ly_scm2interval (end_ys));
 358   else
 359     best = state.get_best_curve ();
 360
 361 #if DEBUG_SLUR_SCORING
 362   if (debug_slurs)
 363     {
 364       string total = best->card ();
 365       total += to_string (" TOTAL=%.2f idx=%d", best->score (), best->index_);
 366       me->set_property ("annotation", ly_string2scm (total));
 367     }
 368 #endif
 369
 370   SCM controls = SCM_EOL;
 371   for (int i = 4; i--;)
 372     {
 373       Offset o = best->curve_.control_[i]
 374                  - Offset (me->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 375                            me->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 376       controls = scm_cons (ly_offset2scm (o), controls);
 377     }
 378
 379   return controls;
 380 }
 381
 382 Slur_configuration *
 383 Slur_score_state::get_forced_configuration (Interval ys) const
 384 {
 385   Slur_configuration *best = NULL;
 386   Real mindist = 1e6;
 387   for (vsize i = 0; i < configurations_.size (); i++)
 388     {
 389       Real d = fabs (configurations_[i]->attachment_[LEFT][Y_AXIS] - ys[LEFT])
 390                + fabs (configurations_[i]->attachment_[RIGHT][Y_AXIS] - ys[RIGHT]);
 391       if (d < mindist)
 392         {
 393           best = configurations_[i];
 394           mindist = d;
 395         }
 396     }
 397
 398   while (!best->done ())
 399     best->run_next_scorer (*this);
 400
 401   if (mindist > 1e5)
 402     programming_error ("cannot find quant");
 403
 404   return best;
 405 }
 406
 407 Slur_configuration *
 408 Slur_score_state::get_best_curve () const
 409 {
 410   std::priority_queue < Slur_configuration *, std::vector<Slur_configuration *>,
 411       Slur_configuration_less > queue;
 412   for (vsize i = 0; i < configurations_.size (); i++)
 413     queue.push (configurations_[i]);
 414
 415   Slur_configuration *best = NULL;
 416   while (true)
 417     {
 418       best = queue.top ();
 419       if (best->done ())
 420         break;
 421
 422       queue.pop ();
 423       best->run_next_scorer (*this);
 424       queue.push (best);
 425     }
 426
 427   return best;
 428 }
 429
 430 Interval
 431 Slur_score_state::breakable_bound_extent (Direction d) const
 432 {
 433   Grob *col = slur_->get_bound (d)->get_column ();
 434   Interval ret;
 435   ret.set_empty ();
 436
 437   extract_grob_set (slur_, "encompass-objects", extra_encompasses);
 438
 439   for (vsize i = 0; i < extra_encompasses.size (); i++)
 440     {
 441       Item *item = dynamic_cast<Item *> (extra_encompasses[i]);
 442       if (item && col == item->get_column ())
 443         ret.unite (robust_relative_extent (item, common_[X_AXIS], X_AXIS));
 444     }
 445
 446   return ret;
 447 }
 448
 449 /*
 450   TODO: should analyse encompasses to determine sensible region, and
 451   should limit slopes available.
 452 */
 453
 454 Drul_array<Real>
 455 Slur_score_state::get_y_attachment_range () const
 456 {
 457   Drul_array<Real> end_ys;
 458   for (LEFT_and_RIGHT (d))
 459     {
 460       if (extremes_[d].note_column_)
 461         {
 462           Interval nc_extent = extremes_[d].note_column_
 463                                ->extent (common_[Y_AXIS], Y_AXIS);
 464           if (nc_extent.is_empty ())
 465             slur_->warning ("slur trying to encompass an empty note column.");
 466           else
 467             end_ys[d] = dir_
 468                         * max (max (dir_ * (base_attachments_[d][Y_AXIS]
 469                                             + parameters_.region_size_ * dir_),
 470                                     dir_ * (dir_ + nc_extent[dir_])),
 471                                dir_ * base_attachments_[-d][Y_AXIS]);
 472         }
 473       else
 474         end_ys[d] = base_attachments_[d][Y_AXIS] + parameters_.region_size_ * dir_;
 475     }
 476
 477   return end_ys;
 478 }
 479
 480 bool
 481 spanner_less (Spanner *s1, Spanner *s2)
 482 {
 483   Slice b1, b2;
 484   for (LEFT_and_RIGHT (d))
 485     {
 486       b1[d] = s1->get_bound (d)->get_column ()->get_rank ();
 487       b2[d] = s2->get_bound (d)->get_column ()->get_rank ();
 488     }
 489
 490   return b2[LEFT] <= b1[LEFT] && b2[RIGHT] >= b1[RIGHT]
 491          && (b2[LEFT] != b1[LEFT] || b2[RIGHT] != b1[RIGHT]);
 492 }
 493
 494 Drul_array<Offset>
 495 Slur_score_state::get_base_attachments () const
 496 {
 497   Drul_array<Offset> base_attachment;
 498   for (LEFT_and_RIGHT (d))
 499     {
 500       Grob *stem = extremes_[d].stem_;
 501       Grob *head = extremes_[d].slur_head_;
 502
 503       Real x = 0.0;
 504       Real y = 0.0;
 505       if (extremes_[d].note_column_)
 506         {
 507
 508           /*
 509             fixme: X coord should also be set in this case.
 510           */
 511           if (stem
 512               && !Stem::is_invisible (stem)
 513               && extremes_[d].stem_dir_ == dir_
 514               && Stem::get_beaming (stem, -d)
 515               && Stem::get_beam (stem)
 516               && (!spanner_less (slur_, Stem::get_beam (stem))
 517                   || has_same_beam_))
 518             y = extremes_[d].stem_extent_[Y_AXIS][dir_];
 519           else if (head)
 520             y = head->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 521           y += dir_ * 0.5 * staff_space_;
 522
 523           y = move_away_from_staffline (y, head);
 524
 525           Grob *fh = Note_column::first_head (extremes_[d].note_column_);
 526           x
 527             = (fh ? fh->extent (common_[X_AXIS], X_AXIS)
 528                : extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS))
 529               .linear_combination (CENTER);
 530         }
 531       base_attachment[d] = Offset (x, y);
 532     }
 533
 534   for (LEFT_and_RIGHT (d))
 535     {
 536       if (!extremes_[d].note_column_)
 537         {
 538           Real x = 0;
 539           Real y = 0;
 540
 541           Interval ext = breakable_bound_extent (d);
 542           if (ext.is_empty ())
 543             ext = Axis_group_interface::
 544                   generic_bound_extent (extremes_[d].bound_,
 545                                         common_[X_AXIS], X_AXIS);
 546           x = ext[-d];
 547
 548           Grob *col = (d == LEFT) ? columns_[0] : columns_.back ();
 549
 550           if (extremes_[-d].bound_ != col)
 551             {
 552               y = robust_relative_extent (col, common_[Y_AXIS], Y_AXIS)[dir_];
 553               y += dir_ * 0.5 * staff_space_;
 554
 555               if (get_grob_direction (col) == dir_
 556                   && Note_column::get_stem (col)
 557                   && !Stem::is_invisible (Note_column::get_stem (col)))
 558                 y -= dir_ * 1.5 * staff_space_;
 559             }
 560           else
 561             y = base_attachment[-d][Y_AXIS];
 562
 563           y = move_away_from_staffline (y, col);
 564
 565           base_attachment[d] = Offset (x, y);
 566         }
 567     }
 568
 569   for (LEFT_and_RIGHT (d))
 570     {
 571       for (int a = X_AXIS; a < NO_AXES; a++)
 572         {
 573           Real &b = base_attachment[d][Axis (a)];
 574
 575           if (isinf (b) || isnan (b))
 576             {
 577               programming_error ("slur attachment is inf/nan");
 578               b = 0.0;
 579             }
 580         }
 581     }
 582
 583   return base_attachment;
 584 }
 585
 586 Real
 587 Slur_score_state::move_away_from_staffline (Real y,
 588                                             Grob *on_staff) const
 589 {
 590   if (!on_staff)
 591     return y;
 592
 593   Grob *staff_symbol = Staff_symbol_referencer::get_staff_symbol (on_staff);
 594   if (!staff_symbol)
 595     return y;
 596
 597   Real pos
 598     = (y - staff_symbol->relative_coordinate (common_[Y_AXIS],
 599                                               Y_AXIS))
 600       * 2.0 / staff_space_;
 601
 602   if (fabs (pos - my_round (pos)) < 0.2
 603       && Staff_symbol_referencer::on_staff_line (on_staff, (int) rint (pos)))
 604     y += 1.5 * staff_space_ * dir_ / 10;
 605
 606   return y;
 607 }
 608
 609 vector<Offset>
 610 Slur_score_state::generate_avoid_offsets () const
 611 {
 612   vector<Offset> avoid;
 613   vector<Grob *> encompasses = columns_;
 614
 615   for (vsize i = 0; i < encompasses.size (); i++)
 616     {
 617       if (extremes_[LEFT].note_column_ == encompasses[i]
 618           || extremes_[RIGHT].note_column_ == encompasses[i])
 619         continue;
 620
 621       Encompass_info inf (get_encompass_info (encompasses[i]));
 622       Real y = dir_ * (max (dir_ * inf.head_, dir_ * inf.stem_));
 623
 624       avoid.push_back (Offset (inf.x_, y + dir_ * parameters_.free_head_distance_));
 625     }
 626
 627   extract_grob_set (slur_, "encompass-objects", extra_encompasses);
 628   for (vsize i = 0; i < extra_encompasses.size (); i++)
 629     {
 630       if (has_interface<Slur> (extra_encompasses[i]))
 631         {
 632           Grob *small_slur = extra_encompasses[i];
 633           Bezier b = Slur::get_curve (small_slur);
 634
 635           Offset z = b.curve_point (0.5);
 636           z += Offset (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 637                        small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 638
 639           z[Y_AXIS] += dir_ * parameters_.free_slur_distance_;
 640           avoid.push_back (z);
 641         }
 642       else if (scm_is_eq (extra_encompasses[i]->get_property ("avoid-slur"),
 643                           ly_symbol2scm ("inside")))
 644         {
 645           Grob *g = extra_encompasses [i];
 646           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 647           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 648
 649           if (!xe.is_empty ()
 650               && !ye.is_empty ())
 651             avoid.push_back (Offset (xe.center (), ye[dir_]));
 652         }
 653     }
 654   return avoid;
 655 }
 656
 657 void
 658 Slur_score_state::generate_curves () const
 659 {
 660   Real r_0 = robust_scm2double (slur_->get_property ("ratio"), 0.33);
 661   Real h_inf = staff_space_ * scm_to_double (slur_->get_property ("height-limit"));
 662
 663   vector<Offset> avoid = generate_avoid_offsets ();
 664   for (vsize i = 0; i < configurations_.size (); i++)
 665     configurations_[i]->generate_curve (*this, r_0, h_inf, avoid);
 666 }
 667
 668 vector<Slur_configuration *>
 669 Slur_score_state::enumerate_attachments (Drul_array<Real> end_ys) const
 670 {
 671   vector<Slur_configuration *> scores;
 672
 673   Drul_array<Offset> os;
 674   os[LEFT] = base_attachments_[LEFT];
 675   Real minimum_length = staff_space_
 676                         * robust_scm2double (slur_->get_property ("minimum-length"), 2.0);
 677
 678   for (int i = 0; dir_ * os[LEFT][Y_AXIS] <= dir_ * end_ys[LEFT]; i++)
 679     {
 680       os[RIGHT] = base_attachments_[RIGHT];
 681       for (int j = 0; dir_ * os[RIGHT][Y_AXIS] <= dir_ * end_ys[RIGHT]; j++)
 682         {
 683
 684           Drul_array<bool> attach_to_stem (false, false);
 685           for (LEFT_and_RIGHT (d))
 686             {
 687               os[d][X_AXIS] = base_attachments_[d][X_AXIS];
 688               if (extremes_[d].stem_
 689                   && !Stem::is_invisible (extremes_[d].stem_)
 690                   && extremes_[d].stem_dir_ == dir_)
 691                 {
 692                   Interval stem_y = extremes_[d].stem_extent_[Y_AXIS];
 693                   stem_y.widen (0.25 * staff_space_);
 694                   if (stem_y.contains (os[d][Y_AXIS]))
 695                     {
 696                       os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS][-d]
 697                                       - d * 0.3;
 698                       attach_to_stem[d] = true;
 699                     }
 700                   else if (dir_ * extremes_[d].stem_extent_[Y_AXIS][dir_]
 701                            < dir_ * os[d][Y_AXIS]
 702                            && !extremes_[d].stem_extent_[X_AXIS].is_empty ())
 703
 704                     os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS].center ();
 705                 }
 706             }
 707
 708           Offset dz;
 709           dz = os[RIGHT] - os[LEFT];
 710           if (dz[X_AXIS] < minimum_length
 711               || fabs (dz[Y_AXIS] / dz[X_AXIS]) > parameters_.max_slope_)
 712             {
 713               for (LEFT_and_RIGHT (d))
 714                 {
 715                   if (extremes_[d].slur_head_
 716                       && !extremes_[d].slur_head_x_extent_.is_empty ())
 717                     {
 718                       os[d][X_AXIS] = extremes_[d].slur_head_x_extent_.center ();
 719                       attach_to_stem[d] = false;
 720                     }
 721                 }
 722             }
 723
 724           dz = os[RIGHT] - os[LEFT];
 725           for (LEFT_and_RIGHT (d))
 726             {
 727               if (extremes_[d].slur_head_
 728                   && !attach_to_stem[d])
 729                 {
 730                   /* Horizontally move tilted slurs a little.  Move
 731                      more for bigger tilts.
 732
 733                      TODO: parameter */
 734                   os[d][X_AXIS]
 735                   -= dir_ * extremes_[d].slur_head_x_extent_.length ()
 736                      * sin (dz.arg ()) / 3;
 737                 }
 738             }
 739
 740           scores.push_back (Slur_configuration::new_config (os, scores.size ()));
 741
 742           os[RIGHT][Y_AXIS] += dir_ * staff_space_ / 2;
 743         }
 744
 745       os[LEFT][Y_AXIS] += dir_ * staff_space_ / 2;
 746     }
 747
 748   assert (scores.size () > 0);
 749   return scores;
 750 }
 751
 752 vector<Extra_collision_info>
 753 Slur_score_state::get_extra_encompass_infos () const
 754 {
 755   extract_grob_set (slur_, "encompass-objects", encompasses);
 756   vector<Extra_collision_info> collision_infos;
 757   for (vsize i = encompasses.size (); i--;)
 758     {
 759       if (has_interface<Slur> (encompasses[i]))
 760         {
 761           Spanner *small_slur = dynamic_cast<Spanner *> (encompasses[i]);
 762           Bezier b = Slur::get_curve (small_slur);
 763
 764           Offset relative (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 765                            small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 766
 767           for (int k = 0; k < 3; k++)
 768             {
 769               Direction hdir = Direction (k - 1);
 770
 771               /*
 772                 Only take bound into account if small slur starts
 773                 together with big slur.
 774               */
 775               if (hdir && small_slur->get_bound (hdir) != slur_->get_bound (hdir))
 776                 continue;
 777
 778               Offset z = b.curve_point (k / 2.0);
 779               z += relative;
 780
 781               Interval yext;
 782               yext.set_full ();
 783               yext[dir_] = z[Y_AXIS] + dir_ * thickness_ * 1.0;
 784
 785               Interval xext (-1, 1);
 786               xext = xext * (thickness_ * 2) + z[X_AXIS];
 787               Extra_collision_info info (small_slur,
 788                                          hdir,
 789                                          xext,
 790                                          yext,
 791                                          parameters_.extra_object_collision_penalty_);
 792               collision_infos.push_back (info);
 793             }
 794         }
 795       else
 796         {
 797           Grob *g = encompasses [i];
 798           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 799           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 800           if (has_interface<Dots> (g))
 801             ye.widen (0.2);
 802
 803           Real xp = 0.0;
 804           Real penalty = parameters_.extra_object_collision_penalty_;
 805           if (has_interface<Accidental_interface> (g))
 806             {
 807               penalty = parameters_.accidental_collision_;
 808
 809               Rational alt = ly_scm2rational (g->get_property ("alteration"));
 810               SCM scm_style = g->get_property ("style");
 811               if (!scm_is_symbol (scm_style)
 812                   && !to_boolean (g->get_property ("parenthesized"))
 813                   && !to_boolean (g->get_property ("restore-first")))
 814                 {
 815                   /* End copy accidental.cc */
 816                   if (alt == FLAT_ALTERATION
 817                       || alt == DOUBLE_FLAT_ALTERATION)
 818                     xp = LEFT;
 819                   else if (alt == SHARP_ALTERATION)
 820                     xp = 0.5 * dir_;
 821                   else if (alt == NATURAL_ALTERATION)
 822                     xp = -dir_;
 823                 }
 824             }
 825
 826           ye.widen (thickness_ * 0.5);
 827           xe.widen (thickness_ * 1.0);
 828           Extra_collision_info info (g, xp, xe, ye, penalty);
 829           collision_infos.push_back (info);
 830         }
 831     }
 832
 833   return collision_infos;
 834 }
 835
 836 Extra_collision_info::Extra_collision_info (Grob *g, Real idx, Interval x, Interval y, Real p)
 837 {
 838   idx_ = idx;
 839   extents_[X_AXIS] = x;
 840   extents_[Y_AXIS] = y;
 841   penalty_ = p;
 842   grob_ = g;
 843   type_ = g->get_property ("avoid-slur");
 844 }
 845
 846 Extra_collision_info::Extra_collision_info ()
 847 {
 848   idx_ = 0.0;
 849   penalty_ = 0.;
 850   grob_ = 0;
 851   type_ = SCM_EOL;
 852 }