lily/slur-scoring.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1996--2012 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 "accidental-interface.hh"
  26 #include "beam.hh"
  27 #include "clef.hh"
  28 #include "directional-element-interface.hh"
  29 #include "dots.hh"
  30 #include "libc-extension.hh"
  31 #include "main.hh"
  32 #include "misc.hh"
  33 #include "note-column.hh"
  34 #include "output-def.hh"
  35 #include "paper-column.hh"
  36 #include "pitch.hh"
  37 #include "pointer-group-interface.hh"
  38 #include "slur-configuration.hh"
  39 #include "slur.hh"
  40 #include "spanner.hh"
  41 #include "staff-symbol-referencer.hh"
  42 #include "staff-symbol.hh"
  43 #include "stem.hh"
  44 #include "time-signature.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 (Note_column::has_interface (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   Real lt = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 229   thickness_ = robust_scm2double (me->get_property ("thickness"), 1.0) * lt;
 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 (extra_encompass_infos_[i].type_ == ly_symbol2scm ("inside")
 285           && minmax (dir_, encompass_place, y_place) == encompass_place
 286           && (!extra_encompass_infos_[i].grob_->internal_has_interface (ly_symbol2scm ("key-signature-interface"))
 287               && !Clef::has_interface (extra_encompass_infos_[i].grob_)
 288               && !Time_signature::has_interface (extra_encompass_infos_[i].grob_)))
 289         {
 290           for (LEFT_and_RIGHT (d))
 291             additional_ys[d] = minmax (dir_,
 292                                        additional_ys[d],
 293                                        (dir_
 294                                         * (parameters_.encompass_object_range_overshoot_
 295                                            + (y_place - encompass_place)
 296                                            * (normalize (extra_encompass_infos_[i].extents_[X_AXIS].center (),
 297                                                          base_attachments_[RIGHT][X_AXIS],
 298                                                          base_attachments_[LEFT][X_AXIS])
 299                                               + (dir_ == LEFT ? 0 : -1)))));
 300         }
 301     }
 302
 303   for (LEFT_and_RIGHT (d))
 304     end_ys[d] += additional_ys[d];
 305
 306   configurations_ = enumerate_attachments (end_ys);
 307   for (vsize i = 0; i < columns_.size (); i++)
 308     encompass_infos_.push_back (get_encompass_info (columns_[i]));
 309
 310   valid_ = true;
 311
 312   musical_dy_ = 0.0;
 313   for (LEFT_and_RIGHT (d))
 314     {
 315       if (!is_broken_
 316           && extremes_[d].slur_head_)
 317         musical_dy_ += d
 318                        * extremes_[d].slur_head_->relative_coordinate (common_[Y_AXIS], Y_AXIS);
 319     }
 320
 321   edge_has_beams_
 322     = (extremes_[LEFT].stem_ && Stem::get_beam (extremes_[LEFT].stem_))
 323       || (extremes_[RIGHT].stem_ && Stem::get_beam (extremes_[RIGHT].stem_));
 324
 325   if (is_broken_)
 326     musical_dy_ = 0.0;
 327 }
 328
 329 MAKE_SCHEME_CALLBACK (Slur, calc_control_points, 1)
 330 SCM
 331 Slur::calc_control_points (SCM smob)
 332 {
 333   Spanner *me = unsmob_spanner (smob);
 334
 335   Slur_score_state state;
 336   state.fill (me);
 337
 338   if (!state.valid_)
 339     return SCM_EOL;
 340
 341   state.generate_curves ();
 342
 343   SCM end_ys = me->get_property ("positions");
 344   SCM inspect_quants = me->get_property ("inspect-quants");
 345   bool debug_slurs = to_boolean (me->layout ()
 346                                  ->lookup_variable (ly_symbol2scm ("debug-slur-scoring")));
 347
 348   if (is_number_pair (inspect_quants))
 349     {
 350       debug_slurs = true;
 351       end_ys = inspect_quants;
 352     }
 353
 354   Slur_configuration *best = NULL;
 355   if (is_number_pair (end_ys))
 356     best = state.get_forced_configuration (ly_scm2interval (end_ys));
 357   else
 358     best = state.get_best_curve ();
 359
 360 #if DEBUG_SLUR_SCORING
 361   if (debug_slurs)
 362     {
 363       string total = best->card ();
 364       total += to_string (" TOTAL=%.2f idx=%d", best->score (), best->index_);
 365       me->set_property ("annotation", ly_string2scm (total));
 366     }
 367 #endif
 368
 369   SCM controls = SCM_EOL;
 370   for (int i = 4; i--;)
 371     {
 372       Offset o = best->curve_.control_[i]
 373                  - Offset (me->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 374                            me->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 375       controls = scm_cons (ly_offset2scm (o), controls);
 376     }
 377
 378   return controls;
 379 }
 380
 381 Slur_configuration *
 382 Slur_score_state::get_forced_configuration (Interval ys) const
 383 {
 384   Slur_configuration *best = NULL;
 385   Real mindist = 1e6;
 386   for (vsize i = 0; i < configurations_.size (); i++)
 387     {
 388       Real d = fabs (configurations_[i]->attachment_[LEFT][Y_AXIS] - ys[LEFT])
 389                + fabs (configurations_[i]->attachment_[RIGHT][Y_AXIS] - ys[RIGHT]);
 390       if (d < mindist)
 391         {
 392           best = configurations_[i];
 393           mindist = d;
 394         }
 395     }
 396
 397   while (!best->done ())
 398     best->run_next_scorer (*this);
 399
 400   if (mindist > 1e5)
 401     programming_error ("cannot find quant");
 402
 403   return best;
 404 }
 405
 406 Slur_configuration *
 407 Slur_score_state::get_best_curve () const
 408 {
 409   std::priority_queue < Slur_configuration *, std::vector<Slur_configuration *>,
 410       Slur_configuration_less > queue;
 411   for (vsize i = 0; i < configurations_.size (); i++)
 412     queue.push (configurations_[i]);
 413
 414   Slur_configuration *best = NULL;
 415   while (true)
 416     {
 417       best = queue.top ();
 418       if (best->done ())
 419         break;
 420
 421       queue.pop ();
 422       best->run_next_scorer (*this);
 423       queue.push (best);
 424     }
 425
 426   return best;
 427 }
 428
 429 Grob *
 430 Slur_score_state::breakable_bound_item (Direction d) const
 431 {
 432   Grob *col = slur_->get_bound (d)->get_column ();
 433
 434   extract_grob_set (slur_, "encompass-objects", extra_encompasses);
 435
 436   for (vsize i = 0; i < extra_encompasses.size (); i++)
 437     {
 438       Item *item = dynamic_cast<Item *> (extra_encompasses[i]);
 439       if (item && col == item->get_column ())
 440         return item;
 441     }
 442
 443   return 0;
 444 }
 445
 446 /*
 447   TODO: should analyse encompasses to determine sensible region, and
 448   should limit slopes available.
 449 */
 450
 451 Drul_array<Real>
 452 Slur_score_state::get_y_attachment_range () const
 453 {
 454   Drul_array<Real> end_ys;
 455   for (LEFT_and_RIGHT (d))
 456     {
 457       if (extremes_[d].note_column_)
 458         {
 459           end_ys[d] = dir_
 460                       * max (max (dir_ * (base_attachments_[d][Y_AXIS]
 461                                           + parameters_.region_size_ * dir_),
 462                                   dir_ * (dir_ + extremes_[d].note_column_->extent (common_[Y_AXIS], Y_AXIS)[dir_])),
 463                              dir_ * base_attachments_[-d][Y_AXIS]);
 464         }
 465       else
 466         end_ys[d] = base_attachments_[d][Y_AXIS] + parameters_.region_size_ * dir_;
 467     }
 468
 469   return end_ys;
 470 }
 471
 472 bool
 473 spanner_less (Spanner *s1, Spanner *s2)
 474 {
 475   Slice b1, b2;
 476   for (LEFT_and_RIGHT (d))
 477     {
 478       b1[d] = s1->get_bound (d)->get_column ()->get_rank ();
 479       b2[d] = s2->get_bound (d)->get_column ()->get_rank ();
 480     }
 481
 482   return b2[LEFT] <= b1[LEFT] && b2[RIGHT] >= b1[RIGHT]
 483          && (b2[LEFT] != b1[LEFT] || b2[RIGHT] != b1[RIGHT]);
 484 }
 485
 486 Drul_array<Offset>
 487 Slur_score_state::get_base_attachments () const
 488 {
 489   Drul_array<Offset> base_attachment;
 490   for (LEFT_and_RIGHT (d))
 491     {
 492       Grob *stem = extremes_[d].stem_;
 493       Grob *head = extremes_[d].slur_head_;
 494
 495       Real x = 0.0;
 496       Real y = 0.0;
 497       if (extremes_[d].note_column_)
 498         {
 499
 500           /*
 501             fixme: X coord should also be set in this case.
 502           */
 503           if (stem
 504               && !Stem::is_invisible (stem)
 505               && extremes_[d].stem_dir_ == dir_
 506               && Stem::get_beaming (stem, -d)
 507               && Stem::get_beam (stem)
 508               && (!spanner_less (slur_, Stem::get_beam (stem))
 509                   || has_same_beam_))
 510             y = extremes_[d].stem_extent_[Y_AXIS][dir_];
 511           else if (head)
 512             y = head->extent (common_[Y_AXIS], Y_AXIS)[dir_];
 513           y += dir_ * 0.5 * staff_space_;
 514
 515           y = move_away_from_staffline (y, head);
 516
 517           Grob *fh = Note_column::first_head (extremes_[d].note_column_);
 518           x
 519             = (fh ? fh->extent (common_[X_AXIS], X_AXIS)
 520                : extremes_[d].bound_->extent (common_[X_AXIS], X_AXIS))
 521               .linear_combination (CENTER);
 522         }
 523       base_attachment[d] = Offset (x, y);
 524     }
 525
 526   for (LEFT_and_RIGHT (d))
 527     {
 528       if (!extremes_[d].note_column_)
 529         {
 530           Real x = 0;
 531           Real y = 0;
 532
 533           if (Grob *g = breakable_bound_item (d))
 534             {
 535               x = robust_relative_extent (g, common_[X_AXIS], X_AXIS)[RIGHT];
 536             }
 537           else if (d == RIGHT)
 538             x = robust_relative_extent (extremes_[d].bound_, common_[X_AXIS], X_AXIS)[d];
 539           else
 540             x = slur_->get_broken_left_end_align ();
 541
 542           Grob *col = (d == LEFT) ? columns_[0] : columns_.back ();
 543
 544           if (extremes_[-d].bound_ != col)
 545             {
 546               y = robust_relative_extent (col, common_[Y_AXIS], Y_AXIS)[dir_];
 547               y += dir_ * 0.5 * staff_space_;
 548
 549               if (get_grob_direction (col) == dir_
 550                   && Note_column::get_stem (col)
 551                   && !Stem::is_invisible (Note_column::get_stem (col)))
 552                 y -= dir_ * 1.5 * staff_space_;
 553             }
 554           else
 555             y = base_attachment[-d][Y_AXIS];
 556
 557           y = move_away_from_staffline (y, col);
 558
 559           base_attachment[d] = Offset (x, y);
 560         }
 561     }
 562
 563   for (LEFT_and_RIGHT (d))
 564     {
 565       for (int a = X_AXIS; a < NO_AXES; a++)
 566         {
 567           Real &b = base_attachment[d][Axis (a)];
 568
 569           if (isinf (b) || isnan (b))
 570             {
 571               programming_error ("slur attachment is inf/nan");
 572               b = 0.0;
 573             }
 574         }
 575     }
 576
 577   return base_attachment;
 578 }
 579
 580 Real
 581 Slur_score_state::move_away_from_staffline (Real y,
 582                                             Grob *on_staff) const
 583 {
 584   if (!on_staff)
 585     return y;
 586
 587   Grob *staff_symbol = Staff_symbol_referencer::get_staff_symbol (on_staff);
 588   if (!staff_symbol)
 589     return y;
 590
 591   Real pos
 592     = (y - staff_symbol->relative_coordinate (common_[Y_AXIS],
 593                                               Y_AXIS))
 594       * 2.0 / staff_space_;
 595
 596   if (fabs (pos - my_round (pos)) < 0.2
 597       && Staff_symbol_referencer::on_staff_line (on_staff, (int) rint (pos)))
 598     y += 1.5 * staff_space_ * dir_ / 10;
 599
 600   return y;
 601 }
 602
 603 vector<Offset>
 604 Slur_score_state::generate_avoid_offsets () const
 605 {
 606   vector<Offset> avoid;
 607   vector<Grob *> encompasses = columns_;
 608
 609   for (vsize i = 0; i < encompasses.size (); i++)
 610     {
 611       if (extremes_[LEFT].note_column_ == encompasses[i]
 612           || extremes_[RIGHT].note_column_ == encompasses[i])
 613         continue;
 614
 615       Encompass_info inf (get_encompass_info (encompasses[i]));
 616       Real y = dir_ * (max (dir_ * inf.head_, dir_ * inf.stem_));
 617
 618       avoid.push_back (Offset (inf.x_, y + dir_ * parameters_.free_head_distance_));
 619     }
 620
 621   extract_grob_set (slur_, "encompass-objects", extra_encompasses);
 622   for (vsize i = 0; i < extra_encompasses.size (); i++)
 623     {
 624       if (Slur::has_interface (extra_encompasses[i]))
 625         {
 626           Grob *small_slur = extra_encompasses[i];
 627           Bezier b = Slur::get_curve (small_slur);
 628
 629           Offset z = b.curve_point (0.5);
 630           z += Offset (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 631                        small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 632
 633           z[Y_AXIS] += dir_ * parameters_.free_slur_distance_;
 634           avoid.push_back (z);
 635         }
 636       else if (extra_encompasses[i]->get_property ("avoid-slur") == ly_symbol2scm ("inside"))
 637         {
 638           Grob *g = extra_encompasses [i];
 639           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 640           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 641
 642           if (!xe.is_empty ()
 643               && !ye.is_empty ())
 644             avoid.push_back (Offset (xe.center (), ye[dir_]));
 645         }
 646     }
 647   return avoid;
 648 }
 649
 650 void
 651 Slur_score_state::generate_curves () const
 652 {
 653   Real r_0 = robust_scm2double (slur_->get_property ("ratio"), 0.33);
 654   Real h_inf = staff_space_ * scm_to_double (slur_->get_property ("height-limit"));
 655
 656   vector<Offset> avoid = generate_avoid_offsets ();
 657   for (vsize i = 0; i < configurations_.size (); i++)
 658     configurations_[i]->generate_curve (*this, r_0, h_inf, avoid);
 659 }
 660
 661 vector<Slur_configuration *>
 662 Slur_score_state::enumerate_attachments (Drul_array<Real> end_ys) const
 663 {
 664   vector<Slur_configuration *> scores;
 665
 666   Drul_array<Offset> os;
 667   os[LEFT] = base_attachments_[LEFT];
 668   Real minimum_length = staff_space_
 669                         * robust_scm2double (slur_->get_property ("minimum-length"), 2.0);
 670
 671   for (int i = 0; dir_ * os[LEFT][Y_AXIS] <= dir_ * end_ys[LEFT]; i++)
 672     {
 673       os[RIGHT] = base_attachments_[RIGHT];
 674       for (int j = 0; dir_ * os[RIGHT][Y_AXIS] <= dir_ * end_ys[RIGHT]; j++)
 675         {
 676
 677           Drul_array<bool> attach_to_stem (false, false);
 678           for (LEFT_and_RIGHT (d))
 679             {
 680               os[d][X_AXIS] = base_attachments_[d][X_AXIS];
 681               if (extremes_[d].stem_
 682                   && !Stem::is_invisible (extremes_[d].stem_)
 683                   && extremes_[d].stem_dir_ == dir_)
 684                 {
 685                   Interval stem_y = extremes_[d].stem_extent_[Y_AXIS];
 686                   stem_y.widen (0.25 * staff_space_);
 687                   if (stem_y.contains (os[d][Y_AXIS]))
 688                     {
 689                       os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS][-d]
 690                                       - d * 0.3;
 691                       attach_to_stem[d] = true;
 692                     }
 693                   else if (dir_ * extremes_[d].stem_extent_[Y_AXIS][dir_]
 694                            < dir_ * os[d][Y_AXIS]
 695                            && !extremes_[d].stem_extent_[X_AXIS].is_empty ())
 696
 697                     os[d][X_AXIS] = extremes_[d].stem_extent_[X_AXIS].center ();
 698                 }
 699             }
 700
 701           Offset dz;
 702           dz = os[RIGHT] - os[LEFT];
 703           if (dz[X_AXIS] < minimum_length
 704               || fabs (dz[Y_AXIS] / dz[X_AXIS]) > parameters_.max_slope_)
 705             {
 706               for (LEFT_and_RIGHT (d))
 707                 {
 708                   if (extremes_[d].slur_head_
 709                       && !extremes_[d].slur_head_x_extent_.is_empty ())
 710                     {
 711                       os[d][X_AXIS] = extremes_[d].slur_head_x_extent_.center ();
 712                       attach_to_stem[d] = false;
 713                     }
 714                 }
 715             }
 716
 717           dz = os[RIGHT] - os[LEFT];
 718           for (LEFT_and_RIGHT (d))
 719             {
 720               if (extremes_[d].slur_head_
 721                   && !attach_to_stem[d])
 722                 {
 723                   /* Horizontally move tilted slurs a little.  Move
 724                      more for bigger tilts.
 725
 726                      TODO: parameter */
 727                   os[d][X_AXIS]
 728                   -= dir_ * extremes_[d].slur_head_x_extent_.length ()
 729                      * sin (dz.arg ()) / 3;
 730                 }
 731             }
 732
 733           scores.push_back (Slur_configuration::new_config (os, scores.size ()));
 734
 735           os[RIGHT][Y_AXIS] += dir_ * staff_space_ / 2;
 736         }
 737
 738       os[LEFT][Y_AXIS] += dir_ * staff_space_ / 2;
 739     }
 740
 741   assert (scores.size () > 0);
 742   return scores;
 743 }
 744
 745 vector<Extra_collision_info>
 746 Slur_score_state::get_extra_encompass_infos () const
 747 {
 748   extract_grob_set (slur_, "encompass-objects", encompasses);
 749   vector<Extra_collision_info> collision_infos;
 750   for (vsize i = encompasses.size (); i--;)
 751     {
 752       if (Slur::has_interface (encompasses[i]))
 753         {
 754           Spanner *small_slur = dynamic_cast<Spanner *> (encompasses[i]);
 755           Bezier b = Slur::get_curve (small_slur);
 756
 757           Offset relative (small_slur->relative_coordinate (common_[X_AXIS], X_AXIS),
 758                            small_slur->relative_coordinate (common_[Y_AXIS], Y_AXIS));
 759
 760           for (int k = 0; k < 3; k++)
 761             {
 762               Direction hdir = Direction (k - 1);
 763
 764               /*
 765                 Only take bound into account if small slur starts
 766                 together with big slur.
 767               */
 768               if (hdir && small_slur->get_bound (hdir) != slur_->get_bound (hdir))
 769                 continue;
 770
 771               Offset z = b.curve_point (k / 2.0);
 772               z += relative;
 773
 774               Interval yext;
 775               yext.set_full ();
 776               yext[dir_] = z[Y_AXIS] + dir_ * thickness_ * 1.0;
 777
 778               Interval xext (-1, 1);
 779               xext = xext * (thickness_ * 2) + z[X_AXIS];
 780               Extra_collision_info info (small_slur,
 781                                          hdir,
 782                                          xext,
 783                                          yext,
 784                                          parameters_.extra_object_collision_penalty_);
 785               collision_infos.push_back (info);
 786             }
 787         }
 788       else
 789         {
 790           Grob *g = encompasses [i];
 791           Interval xe = g->extent (common_[X_AXIS], X_AXIS);
 792           Interval ye = g->extent (common_[Y_AXIS], Y_AXIS);
 793           if (Dots::has_interface (g))
 794             ye.widen (0.2);
 795
 796           Real xp = 0.0;
 797           Real penalty = parameters_.extra_object_collision_penalty_;
 798           if (Accidental_interface::has_interface (g))
 799             {
 800               penalty = parameters_.accidental_collision_;
 801
 802               Rational alt = ly_scm2rational (g->get_property ("alteration"));
 803               SCM scm_style = g->get_property ("style");
 804               if (!scm_is_symbol (scm_style)
 805                   && !to_boolean (g->get_property ("parenthesized"))
 806                   && !to_boolean (g->get_property ("restore-first")))
 807                 {
 808                   /* End copy accidental.cc */
 809                   if (alt == FLAT_ALTERATION
 810                       || alt == DOUBLE_FLAT_ALTERATION)
 811                     xp = LEFT;
 812                   else if (alt == SHARP_ALTERATION)
 813                     xp = 0.5 * dir_;
 814                   else if (alt == NATURAL_ALTERATION)
 815                     xp = -dir_;
 816                 }
 817             }
 818
 819           ye.widen (thickness_ * 0.5);
 820           xe.widen (thickness_ * 1.0);
 821           Extra_collision_info info (g, xp, xe, ye, penalty);
 822           collision_infos.push_back (info);
 823         }
 824     }
 825
 826   return collision_infos;
 827 }
 828
 829 Extra_collision_info::Extra_collision_info (Grob *g, Real idx, Interval x, Interval y, Real p)
 830 {
 831   idx_ = idx;
 832   extents_[X_AXIS] = x;
 833   extents_[Y_AXIS] = y;
 834   penalty_ = p;
 835   grob_ = g;
 836   type_ = g->get_property ("avoid-slur");
 837 }
 838
 839 Extra_collision_info::Extra_collision_info ()
 840 {
 841   idx_ = 0.0;
 842   penalty_ = 0.;
 843   grob_ = 0;
 844   type_ = SCM_EOL;
 845 }