lily/slur.cc

   1 /*
   2   slur.cc -- implement  Slur
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7     Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 /*
  11   [TODO]
  12     * should avoid stafflines with horizontal part.
  13     * begin and end should be treated as a/acknowledge Scripts.
  14     * smart changing of endings
  15     * smart changing of (Y-?)offsets to avoid ugly beziers
  16  (along-side-stem)
  17  */
  18
  19 #include "directional-element-interface.hh"
  20 #include "group-interface.hh"
  21 #include "slur.hh"
  22 #include "lookup.hh"
  23 #include "paper-def.hh"
  24 #include "note-column.hh"
  25 #include "stem.hh"
  26 #include "paper-column.hh"
  27 #include "molecule.hh"
  28 #include "debug.hh"
  29 #include "slur-bezier-bow.hh"
  30 #include "main.hh"
  31 #include "group-interface.hh"
  32 #include "staff-symbol-referencer.hh"
  33 #include "spanner.hh"
  34
  35
  36 void
  37 Slur::set_interface (Grob*me)
  38 {
  39   /* Copy to mutable list. */
  40   me->set_grob_property ("attachment",
  41                          ly_deep_copy (me->get_grob_property ("attachment")));
  42 }
  43
  44 void
  45 Slur::add_column (Grob*me, Grob*n)
  46 {
  47   if (!gh_pair_p (n->get_grob_property ("note-heads")))
  48     warning (_ ("Putting slur over rest.  Ignoring."));
  49   else
  50     {
  51       Pointer_group_interface::add_element (me, "note-columns",n);
  52       me->add_dependency (n);
  53     }
  54
  55   add_bound_item (dynamic_cast<Spanner*> (me), dynamic_cast<Item*> (n));
  56 }
  57
  58 void
  59 Slur::de_uglyfy (Grob*me, Slur_bezier_bow* bb, Real default_height)
  60 {
  61   Real length = bb->curve_.control_[3][X_AXIS] ;
  62   Real ff = bb->fit_factor ();
  63   for (int i = 1; i < 3; i++)
  64     {
  65       Real ind = abs (bb->curve_.control_[ (i-1)*3][X_AXIS]
  66                       - bb->curve_.control_[i][X_AXIS]) / length;
  67       Real h = bb->curve_.control_[i][Y_AXIS] * ff / length;
  68
  69       Real f = default_height / length;
  70       SCM up = me->get_grob_property ("de-uglify-parameters");
  71
  72       Real c1 = gh_scm2double (gh_car (up));
  73       Real c2 = gh_scm2double (gh_cadr (up));
  74       Real c3 = gh_scm2double (gh_caddr (up));
  75
  76       if (h > c1 * f)
  77         {
  78           h = c1 * f;
  79         }
  80       else if (h > c2 + c3 * ind)
  81         {
  82           h = c2 + c3 * ind;
  83         }
  84
  85       bb->curve_.control_[i][Y_AXIS] = h * length;
  86     }
  87
  88   bb->curve_.assert_sanity ();
  89 }
  90
  91 Direction
  92 Slur::get_default_dir (Grob*me)
  93 {
  94   Link_array<Grob> encompass_arr =
  95     Pointer_group_interface__extract_elements (me, (Grob*)0, "note-columns");
  96
  97   Direction d = DOWN;
  98   for (int i=0; i < encompass_arr.size (); i ++)
  99     {
 100       if (Note_column::dir (encompass_arr[i]) < 0)
 101         {
 102           d = UP;
 103           break;
 104         }
 105     }
 106   return d;
 107 }
 108
 109
 110 MAKE_SCHEME_CALLBACK (Slur, after_line_breaking,1);
 111 SCM
 112 Slur::after_line_breaking (SCM smob)
 113 {
 114   Grob *me = unsmob_grob (smob);
 115   if (!scm_ilength (me->get_grob_property ("note-columns")))
 116     {
 117       me->suicide ();
 118       return SCM_UNSPECIFIED;
 119     }
 120   set_extremities (me);
 121   set_control_points (me);
 122   return SCM_UNSPECIFIED;
 123 }
 124
 125
 126 void
 127 Slur::check_slope (Grob *me)
 128 {
 129   /*
 130     Avoid too steep slurs.
 131    */
 132   SCM s = me->get_grob_property ("slope-limit");
 133   if (gh_number_p (s))
 134     {
 135       Array<Offset> encompass = get_encompass_offset_arr (me);
 136       Drul_array<Offset> attachment;
 137       attachment[LEFT] = encompass[0];
 138       attachment[RIGHT] = encompass.top ();
 139
 140       Real dx = attachment[RIGHT][X_AXIS] - attachment[LEFT][X_AXIS];
 141       Real dy = attachment[RIGHT][Y_AXIS] - attachment[LEFT][Y_AXIS];
 142       if (!dx)
 143         return;
 144
 145       Real slope = slope = abs (dy / dx);
 146
 147       Real limit = gh_scm2double (s);
 148
 149       if (slope > limit)
 150         {
 151           Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
 152           Direction dir = (Direction)gh_scm2int (me->get_grob_property ("direction"));
 153           Direction d = (Direction) (- dir * (sign (dy)));
 154           SCM a = me->get_grob_property ("attachment-offset");
 155           Drul_array<Offset> o;
 156           o[LEFT] = ly_scm2offset (index_cell (a, LEFT));
 157           o[RIGHT] = ly_scm2offset (index_cell (a, RIGHT));
 158           o[d][Y_AXIS] -= (limit - slope) * dx * dir / staff_space;
 159
 160           o[d][Y_AXIS] *= Directional_element_interface::get (me);
 161
 162           me->set_grob_property ("attachment-offset",
 163                                 gh_cons (ly_offset2scm (o[LEFT]),
 164                                          ly_offset2scm (o[RIGHT])));
 165         }
 166     }
 167 }
 168
 169 void
 170 Slur::set_extremities (Grob *me)
 171 {
 172   if (!Directional_element_interface::get (me))
 173     Directional_element_interface::set (me, get_default_dir (me));
 174
 175   Direction dir = LEFT;
 176   do
 177     {
 178       if (!gh_symbol_p (index_cell (me->get_grob_property ("attachment"), dir)))
 179         {
 180           for (SCM s = me->get_grob_property ("extremity-rules");
 181                s != SCM_EOL; s = gh_cdr (s))
 182             {
 183               SCM r = gh_call2 (gh_caar (s), me->self_scm (),
 184                                  gh_int2scm ((int)dir));
 185               if (r != SCM_BOOL_F)
 186                 {
 187                   index_set_cell (me->get_grob_property ("attachment"), dir,
 188                                   gh_cdar (s));
 189                   break;
 190                 }
 191             }
 192         }
 193     }
 194   while (flip (&dir) != LEFT);
 195
 196   check_slope (me);
 197 }
 198
 199
 200 Real
 201 Slur::get_first_notecolumn_y (Grob *me, Direction dir)
 202 {
 203   Grob *col = dir == LEFT
 204     ? unsmob_grob (gh_car (scm_reverse (me->get_grob_property
 205  ("note-columns"))))
 206     : unsmob_grob
 207  (gh_car (me->get_grob_property ("note-columns")));
 208
 209   Grob *common[] =
 210   {
 211     0,
 212     me->common_refpoint (col, Y_AXIS)
 213   };
 214   Real y;
 215   if (col == ((Spanner*)me)->get_bound (dir))
 216     {
 217       y = get_attachment (me, dir, common)[Y_AXIS];
 218     }
 219   else
 220     {
 221       y = encompass_offset (me, col, common)[Y_AXIS]
 222         - me->relative_coordinate (common[Y_AXIS], Y_AXIS);
 223     }
 224   return y;
 225 }
 226
 227 Offset
 228 Slur::broken_trend_offset (Grob *me, Direction dir)
 229 {
 230   /*
 231     A broken slur should maintain the same vertical trend
 232     the unbroken slur would have had.
 233   */
 234   Offset o;
 235   if (Spanner *mother =  dynamic_cast<Spanner*> (me->original_l_))
 236     {
 237       for (int i = dir == LEFT ? 0 : mother->broken_into_l_arr_.size () - 1;
 238            dir == LEFT ? i < mother->broken_into_l_arr_.size () : i > 0;
 239            dir == LEFT ? i++ : i--)
 240         {
 241           if (mother->broken_into_l_arr_[i - dir] == me)
 242             {
 243               Grob *neighbour = mother->broken_into_l_arr_[i];
 244               if (dir == RIGHT)
 245                 neighbour->set_grob_property ("direction",
 246                                              me->get_grob_property ("direction"));
 247               Real neighbour_y = get_first_notecolumn_y (neighbour, dir);
 248               Real y = get_first_notecolumn_y (me, -dir);
 249               int neighbour_cols = scm_ilength (neighbour->get_grob_property ("note-columns"));
 250               int cols = scm_ilength (me->get_grob_property ("note-columns"));
 251               o = Offset (0, (y*neighbour_cols + neighbour_y*cols) /
 252  (cols + neighbour_cols));
 253               break;
 254             }
 255         }
 256     }
 257   return o;
 258 }
 259
 260 Offset
 261 Slur::get_attachment (Grob *me, Direction dir,
 262                       Grob **common)
 263 {
 264   SCM s = me->get_grob_property ("attachment");
 265   if (!gh_symbol_p (index_cell (s, dir)))
 266     {
 267       set_extremities (me);
 268       s = me->get_grob_property ("attachment");
 269     }
 270   SCM a = dir == LEFT ? gh_car (s) : gh_cdr (s);
 271   Spanner*sp = dynamic_cast<Spanner*> (me);
 272   String str = ly_symbol2string (a);
 273   Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
 274   Real hs = staff_space / 2.0;
 275   Offset o;
 276
 277   Grob *stem = 0;
 278   if (Note_column::has_interface (sp->get_bound (dir)))
 279     {
 280       Grob * n =sp->get_bound (dir);
 281       if ((stem = Note_column::stem_l (n)))
 282         {
 283           Real x_extent;
 284           if (Grob *head = Note_column::first_head (n))
 285             x_extent = head->extent (head, X_AXIS).length ();
 286           else
 287             x_extent = n->extent (n, X_AXIS).length ();
 288
 289           if (str == "head")
 290             {
 291               o = Offset (0, Stem::head_positions (stem)
 292                           [Directional_element_interface::get (me)] * hs);
 293               /*
 294                 Default position is centered in X, on outer side of head Y
 295                */
 296               o += Offset (0.5 * x_extent,
 297                            0.5 * staff_space
 298                            * Directional_element_interface::get (me));
 299             }
 300           else if (str == "alongside-stem")
 301             {
 302               o = Offset (0, Stem::chord_start_f (stem));
 303               /*
 304                 Default position is on stem X, on outer side of head Y
 305                */
 306               o += Offset (x_extent * (1 + Stem::get_direction (stem)),
 307                            0.5 * staff_space
 308                            * Directional_element_interface::get (me));
 309             }
 310           else if (str == "stem")
 311             {
 312               o = Offset (0, Stem::stem_end_position (stem) * hs);
 313               /*
 314                 Default position is on stem X, at stem end Y
 315                */
 316               o += Offset (0.5 *
 317                            x_extent * (1 + Stem::get_direction (stem)),
 318                            0);
 319             }
 320         }
 321     }
 322   /*
 323     If we're not a note_column, we can't be anything but a loose-end.
 324     But if user has set (attachment . (stem . stem)), our string is
 325     stem, not loose-end.
 326
 327     Hmm, maybe after-line-breaking should set this to loose-end?  */
 328   else // if (str == "loose-end")
 329     {
 330       SCM other_a = dir == LEFT ? gh_cdr (s) : gh_car (s);
 331       if (ly_symbol2string (other_a) != "loose-end")
 332         o = broken_trend_offset (me, dir);
 333     }
 334
 335   SCM alist = me->get_grob_property ("extremity-offset-alist");
 336   int stemdir = stem ? Stem::get_direction (stem) : 1;
 337   int slurdir = gh_scm2int (me->get_grob_property ("direction"));
 338   SCM l = scm_assoc
 339     (scm_list_n (a,
 340                   gh_int2scm (stemdir * dir),
 341                   gh_int2scm (slurdir * dir),
 342                   SCM_UNDEFINED), alist);
 343
 344   if (l != SCM_BOOL_F)
 345     {
 346       Offset off = ly_scm2offset (gh_cdr (l)) * staff_space;
 347       off[X_AXIS] *= dir;
 348       off[Y_AXIS] *= Directional_element_interface::get (me);
 349       o += off;
 350     }
 351
 352   /*
 353     What if get_bound () is not a note-column?
 354    */
 355   if (str != "loose-end"
 356       && sp->get_bound (dir)->common_refpoint (common[Y_AXIS], Y_AXIS) == common[Y_AXIS])
 357     {
 358       o[Y_AXIS] += sp->get_bound (dir)->relative_coordinate (common[Y_AXIS], Y_AXIS)
 359         - me->relative_coordinate (common[Y_AXIS], Y_AXIS);
 360     }
 361
 362   Offset off = ly_scm2offset (index_cell (me->get_grob_property
 363                                           ("attachment-offset"),
 364                                           dir)) * staff_space;
 365
 366   off[Y_AXIS] *= Directional_element_interface::get (me);
 367   o += off;
 368   return o;
 369 }
 370
 371 Offset
 372 Slur::encompass_offset (Grob*me,
 373                         Grob* col,
 374                         Grob **common)
 375 {
 376   Offset o;
 377   Grob* stem_l = unsmob_grob (col->get_grob_property ("stem"));
 378
 379   Direction dir = Directional_element_interface::get (me);
 380
 381   if (!stem_l)
 382     {
 383       warning (_ ("Slur over rest?"));
 384       o[X_AXIS] = col->relative_coordinate (common[X_AXIS], X_AXIS);
 385       o[Y_AXIS] = col->relative_coordinate (common[Y_AXIS], Y_AXIS);
 386       return o;
 387     }
 388   Direction stem_dir = Directional_element_interface::get (stem_l);
 389   o[X_AXIS] = stem_l->relative_coordinate (0, X_AXIS);
 390
 391   /*
 392     Simply set x to middle of notehead
 393    */
 394   Real x_extent;
 395   if (Grob *head = Note_column::first_head (col))
 396     x_extent = head->extent (head, X_AXIS).length ();
 397   else
 398     x_extent = col->extent (col, X_AXIS).length ();
 399   o[X_AXIS] -= 0.5 * stem_dir * x_extent;
 400
 401   if ((stem_dir == dir)
 402       && !stem_l->extent (stem_l, Y_AXIS).empty_b ())
 403     {
 404       o[Y_AXIS] = stem_l->extent (common[Y_AXIS], Y_AXIS)[dir];
 405     }
 406   else
 407     {
 408       o[Y_AXIS] = col->extent (common[Y_AXIS], Y_AXIS)[dir];
 409     }
 410
 411   /*
 412    leave a gap: slur mustn't touch head/stem
 413    */
 414   o[Y_AXIS] += dir * gh_scm2double (me->get_grob_property ("y-free")) *
 415     1.0;
 416   return o;
 417 }
 418
 419 Array<Offset>
 420 Slur::get_encompass_offset_arr (Grob *me)
 421 {
 422   Spanner*sp = dynamic_cast<Spanner*> (me);
 423   SCM eltlist = me->get_grob_property ("note-columns");
 424   Grob *common[] = {me->common_refpoint (eltlist, X_AXIS),
 425                              me->common_refpoint (eltlist, Y_AXIS)};
 426
 427
 428   common[X_AXIS] = common[X_AXIS]->common_refpoint (sp->get_bound (RIGHT), X_AXIS);
 429   common[X_AXIS] = common[X_AXIS]->common_refpoint (sp->get_bound (LEFT), X_AXIS);
 430
 431   Link_array<Grob>  encompass_arr;
 432   while (gh_pair_p (eltlist))
 433     {
 434       encompass_arr.push (unsmob_grob (gh_car (eltlist)));
 435       eltlist =gh_cdr (eltlist);
 436     }
 437   encompass_arr.reverse ();
 438
 439
 440   Array<Offset> offset_arr;
 441
 442   Offset origin (me->relative_coordinate (common[X_AXIS], X_AXIS),
 443                  me->relative_coordinate (common[Y_AXIS], Y_AXIS));
 444
 445   int first = 1;
 446   int last = encompass_arr.size () - 2;
 447
 448   offset_arr.push (get_attachment (me, LEFT, common));
 449
 450   /*
 451     left is broken edge
 452   */
 453
 454   if (encompass_arr[0] != sp->get_bound (LEFT))
 455     {
 456       first--;
 457
 458       // ?
 459       offset_arr[0][Y_AXIS] -=
 460         encompass_arr[0]->relative_coordinate (common[Y_AXIS], Y_AXIS)
 461         - me->relative_coordinate (common[Y_AXIS], Y_AXIS);
 462     }
 463
 464   /*
 465     right is broken edge
 466   */
 467   if (encompass_arr.top () != sp->get_bound (RIGHT))
 468     {
 469       last++;
 470     }
 471
 472   for (int i = first; i <= last; i++)
 473     {
 474       Offset o (encompass_offset (me, encompass_arr[i], common));
 475       offset_arr.push (o - origin);
 476     }
 477
 478   offset_arr.push (Offset (sp->spanner_length (), 0) + get_attachment (me, RIGHT,common));
 479
 480   if (encompass_arr[0] != sp->get_bound (LEFT))
 481     {
 482       offset_arr.top ()[Y_AXIS] -= encompass_arr.top ()->relative_coordinate (common[Y_AXIS], Y_AXIS)
 483         - me->relative_coordinate (common[Y_AXIS], Y_AXIS);
 484     }
 485
 486   return offset_arr;
 487 }
 488
 489
 490
 491
 492 /*
 493   ugh ?
 494  */
 495 MAKE_SCHEME_CALLBACK (Slur, height, 2);
 496 SCM
 497 Slur::height (SCM smob, SCM ax)
 498 {
 499   Axis a = (Axis)gh_scm2int (ax);
 500   Grob * me = unsmob_grob (smob);
 501   assert (a == Y_AXIS);
 502
 503   SCM mol = me->get_uncached_molecule ();
 504   return ly_interval2scm (unsmob_molecule (mol)->extent (a));
 505 }
 506
 507 /*
 508   Ugh should have dash-length + dash-period
 509  */
 510 MAKE_SCHEME_CALLBACK (Slur, brew_molecule,1);
 511 SCM
 512 Slur::brew_molecule (SCM smob)
 513 {
 514   Grob * me = unsmob_grob (smob);
 515   if (!scm_ilength (me->get_grob_property ("note-columns")))
 516     {
 517       me->suicide ();
 518       return SCM_EOL;
 519     }
 520
 521   Real thick = me->paper_l ()->get_var ("stafflinethickness") *
 522     gh_scm2double (me->get_grob_property ("thickness"));
 523   Bezier one = get_curve (me);
 524
 525   // get_curve may suicide
 526   if (!scm_ilength (me->get_grob_property ("note-columns")))
 527     return SCM_EOL;
 528
 529   Molecule a;
 530   SCM d =  me->get_grob_property ("dashed");
 531   if (gh_number_p (d))
 532     a = Lookup::dashed_slur (one, thick, thick * gh_scm2double (d));
 533   else
 534     a = Lookup::slur (one, Directional_element_interface::get (me) * thick, thick);
 535
 536   return a.smobbed_copy ();
 537 }
 538
 539 void
 540 Slur::set_control_points (Grob*me)
 541 {
 542   Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
 543
 544   SCM details = me->get_grob_property ("details");
 545   SCM h_inf_scm = scm_assq (ly_symbol2scm ("height-limit"), details);
 546   SCM r_0_scm = scm_assq (ly_symbol2scm ("ratio"), details);
 547
 548   Real r_0 = gh_scm2double (gh_cdr (r_0_scm));
 549   Real h_inf = staff_space * gh_scm2double (gh_cdr (h_inf_scm));
 550
 551   Slur_bezier_bow bb (get_encompass_offset_arr (me),
 552                       Directional_element_interface::get (me),
 553                       h_inf, r_0);
 554
 555   if (bb.fit_factor () > 1.0)
 556     {
 557       Real length = bb.curve_.control_[3][X_AXIS];
 558       Real default_height = slur_height (length, h_inf, r_0);
 559
 560       SCM ssb = me->get_grob_property ("beautiful");
 561       Real sb = 0;
 562       if (gh_number_p (ssb))
 563         sb = gh_scm2double (ssb);
 564
 565       bb.minimise_enclosed_area (sb, details);
 566       SCM sbf = scm_assq (ly_symbol2scm ("force-blowfit"), details);
 567       Real bff = 1.0;
 568       if (gh_pair_p (sbf) && gh_number_p (gh_cdr (sbf)))
 569           bff = gh_scm2double (gh_cdr (sbf));
 570
 571       bb.curve_.control_[1][Y_AXIS] *= bff;
 572       bb.curve_.control_[2][Y_AXIS] *= bff;
 573       bb.blow_fit ();
 574
 575
 576       Real beautiful = length * default_height * sb;
 577       Real area = bb.enclosed_area_f ();
 578
 579       /*
 580         Slurs that fit beautifully are not ugly
 581       */
 582       if (area > beautiful)
 583         de_uglyfy (me, &bb, default_height);
 584     }
 585
 586   Bezier b = bb.get_bezier ();
 587
 588
 589   SCM controls = SCM_EOL;
 590   for (int i= 4; i--;)
 591     {
 592       controls = gh_cons (ly_offset2scm (b.control_[i]), controls);
 593       /*
 594         BRRR WHURG.
 595         All these null control-points, where do they all come from?
 596       */
 597       if (i && b.control_[i][X_AXIS] == 0)
 598         {
 599           me->suicide ();
 600           return;
 601         }
 602     }
 603
 604   me->set_grob_property ("control-points", controls);
 605 }
 606
 607 Bezier
 608 Slur::get_curve (Grob*me)
 609 {
 610   Bezier b;
 611   int i = 0;
 612
 613   if (!Directional_element_interface::get (me)
 614       || ! gh_symbol_p (index_cell (me->get_grob_property ("attachment"), LEFT))
 615       || ! gh_symbol_p (index_cell (me->get_grob_property ("attachment"), RIGHT)))
 616     set_extremities (me);
 617
 618   if (!gh_pair_p (me->get_grob_property ("control-points")))
 619     set_control_points (me);
 620
 621   // set_control_points may suicide
 622   if (!scm_ilength (me->get_grob_property ("note-columns")))
 623     return b;
 624
 625   for (SCM s= me->get_grob_property ("control-points"); s != SCM_EOL; s = gh_cdr (s))
 626     {
 627       b.control_[i] = ly_scm2offset (gh_car (s));
 628       i++;
 629     }
 630
 631   Array<Offset> enc (get_encompass_offset_arr (me));
 632   Direction dir = Directional_element_interface::get (me);
 633
 634   Real x1 = enc[0][X_AXIS];
 635   Real x2 = enc.top ()[X_AXIS];
 636
 637   Real off = 0.0;
 638   for (int i=1; i < enc.size ()-1; i++)
 639     {
 640       Real x = enc[i][X_AXIS];
 641       if (x > x1 && x <x2)
 642         {
 643           Real y = b.get_other_coordinate (X_AXIS, x);
 644           off = off >? dir * (enc[i][Y_AXIS] - y);
 645         }
 646     }
 647   b.translate (Offset (0, dir * off));
 648   return b;
 649 }
 650
 651
 652 bool
 653 Slur::has_interface (Grob*me)
 654 {
 655   return me->has_interface (ly_symbol2scm ("slur-interface"));
 656 }
 657
 658