lily/stem.cc

   1 /*
   2   stem.cc -- implement Stem
   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   TODO: This is way too hairy
  10 */
  11 #include <math.h>               // m_pi
  12
  13 #include "lookup.hh"
  14 #include "directional-element-interface.hh"
  15 #include "note-head.hh"
  16 #include "stem.hh"
  17 #include "debug.hh"
  18 #include "paper-def.hh"
  19 #include "rhythmic-head.hh"
  20 #include "font-interface.hh"
  21 #include "molecule.hh"
  22 #include "paper-column.hh"
  23 #include "misc.hh"
  24 #include "beam.hh"
  25 #include "rest.hh"
  26 #include "group-interface.hh"
  27 #include "staff-symbol-referencer.hh"
  28 #include "spanner.hh"
  29
  30
  31 void
  32 Stem::set_beaming (Grob*me ,int i,  Direction d)
  33 {
  34   SCM pair = me->get_grob_property ("beaming");
  35
  36   if (!gh_pair_p (pair))
  37     {
  38       pair = gh_cons (gh_int2scm (0),gh_int2scm (0));
  39       me->      set_grob_property ("beaming", pair);
  40     }
  41   index_set_cell (pair, d, gh_int2scm (i));
  42 }
  43
  44 int
  45 Stem::beam_count (Grob*me,Direction d)
  46 {
  47   SCM p=me->get_grob_property ("beaming");
  48   if (gh_pair_p (p))
  49     return gh_scm2int (index_cell (p,d));
  50   else
  51     return 0;
  52 }
  53
  54 Interval
  55 Stem::head_positions (Grob*me)
  56 {
  57   if (!heads_i (me))
  58     {
  59       Interval iv;
  60       return iv;
  61     }
  62
  63   Drul_array<Grob*> e (extremal_heads (me));
  64
  65   return Interval (Staff_symbol_referencer::position_f (e[DOWN]),
  66                    Staff_symbol_referencer::position_f (e[UP]));
  67 }
  68
  69
  70 Real
  71 Stem::chord_start_f (Grob*me)
  72 {
  73   return head_positions (me)[get_direction (me)]
  74     * Staff_symbol_referencer::staff_space (me)/2.0;
  75 }
  76
  77 Real
  78 Stem::stem_end_position (Grob*me)
  79 {
  80   SCM p =me->get_grob_property ("stem-end-position");
  81   Real pos;
  82   if (!gh_number_p (p))
  83     {
  84
  85       pos = get_default_stem_end_position (me);
  86       me->set_grob_property ("stem-end-position", gh_double2scm (pos));
  87     }
  88   else
  89     pos = gh_scm2double (p);
  90
  91   return pos;
  92 }
  93
  94 Direction
  95 Stem::get_direction (Grob*me)
  96 {
  97   Direction d = Directional_element_interface::get (me);
  98
  99   if (!d)
 100     {
 101        d = get_default_dir (me);
 102        // urg, AAARGH!
 103        Directional_element_interface::set (me, d);
 104     }
 105   return d ;
 106 }
 107
 108
 109 void
 110 Stem::set_stemend (Grob*me, Real se)
 111 {
 112   // todo: margins
 113   Direction d= get_direction (me);
 114
 115   if (d && d * head_positions (me)[get_direction (me)] >= se*d)
 116     warning (_ ("Weird stem size; check for narrow beams"));
 117
 118   me->set_grob_property ("stem-end-position", gh_double2scm (se));
 119 }
 120
 121 int
 122 Stem::type_i (Grob*me)
 123 {
 124   return first_head (me) ?  Rhythmic_head::balltype_i (first_head (me)) : 2;
 125 }
 126
 127 /*
 128   Note head that determines hshift for upstems
 129  */
 130 Grob*
 131 Stem::support_head (Grob*me)
 132 {
 133   SCM h = me->get_grob_property ("support-head");
 134   Grob * nh = unsmob_grob (h);
 135   if (nh)
 136     return nh;
 137   else if (heads_i (me) == 1)
 138     {
 139       /*
 140         UGH.
 141        */
 142
 143       return unsmob_grob (gh_car (me->get_grob_property ("heads")));
 144     }
 145   else
 146     return first_head (me);
 147 }
 148
 149
 150 int
 151 Stem::heads_i (Grob*me)
 152 {
 153   return  Pointer_group_interface::count (me, "heads");
 154 }
 155
 156 /*
 157   The note head which forms one end of the stem.
 158  */
 159 Grob*
 160 Stem::first_head (Grob*me)
 161 {
 162   return extremal_heads (me)[-get_direction (me)];
 163 }
 164
 165 /*
 166   START is part where stem reaches `last' head.
 167  */
 168 Drul_array<Grob*>
 169 Stem::extremal_heads (Grob*me)
 170 {
 171   const int inf = 1000000;
 172   Drul_array<int> extpos;
 173   extpos[DOWN] = inf;
 174   extpos[UP] = -inf;
 175
 176   Drul_array<Grob *> exthead;
 177   exthead[LEFT] = exthead[RIGHT] =0;
 178
 179   for (SCM s = me->get_grob_property ("heads"); gh_pair_p (s); s = gh_cdr (s))
 180     {
 181       Grob * n = unsmob_grob (gh_car (s));
 182
 183
 184       int p = int (Staff_symbol_referencer::position_f (n));
 185
 186       Direction d = LEFT;
 187       do {
 188       if (d* p > d* extpos[d])
 189         {
 190           exthead[d] = n;
 191           extpos[d] = p;
 192         }
 193       } while (flip (&d) != DOWN);
 194     }
 195
 196   return exthead;
 197 }
 198
 199 void
 200 Stem::add_head (Grob*me, Grob *n)
 201 {
 202   n->set_grob_property ("stem", me->self_scm ());
 203   n->add_dependency (me);
 204
 205   if (Note_head::has_interface (n))
 206     {
 207       Pointer_group_interface::add_element (me, "heads",n);
 208     }
 209   else
 210     {
 211       n->set_grob_property ("rest", n->self_scm ());
 212     }
 213 }
 214
 215 bool
 216 Stem::invisible_b (Grob*me)
 217 {
 218   return ! (heads_i (me) && Rhythmic_head::balltype_i (support_head (me)) >= 1);
 219 }
 220
 221 int
 222 Stem::get_center_distance (Grob*me, Direction d)
 223 {
 224   int staff_center = 0;
 225   int distance = (int) (d* (head_positions (me)[d] - staff_center));
 226   return distance >? 0;
 227 }
 228
 229 Direction
 230 Stem::get_default_dir (Grob*me)
 231 {
 232   int du = get_center_distance (me,UP);
 233   int dd = get_center_distance (me,DOWN);
 234
 235   if (sign (dd - du))
 236     return Direction (sign (dd -du));
 237
 238   return to_dir (me->get_grob_property ("default-neutral-direction"));
 239 }
 240
 241 Real
 242 Stem::get_default_stem_end_position (Grob*me)
 243 {
 244   bool grace_b = to_boolean (me->get_grob_property ("grace"));
 245   SCM s;
 246   Array<Real> a;
 247
 248   Real length_f = 0.;
 249   SCM scm_len = me->get_grob_property ("length");
 250   if (gh_number_p (scm_len))
 251     {
 252       length_f = gh_scm2double (scm_len);
 253     }
 254   else
 255     {
 256       s = me->get_grob_property ("lengths");
 257       for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 258         a.push (gh_scm2double (gh_car (q)));
 259
 260       // stem uses half-spaces
 261       length_f = a[ ((flag_i (me) - 2) >? 0) <? (a.size () - 1)] * 2;
 262     }
 263
 264
 265   a.clear ();
 266   s = me->get_grob_property ("stem-shorten");
 267   for (SCM q = s; gh_pair_p (q); q = gh_cdr (q))
 268     a.push (gh_scm2double (gh_car (q)));
 269
 270
 271   // stem uses half-spaces
 272
 273   // fixme: use gh_list_ref () iso. array[]
 274   Real shorten_f = a[ ((flag_i (me) - 2) >? 0) <? (a.size () - 1)] * 2;
 275
 276   /* URGURGURG
 277      'set-default-stemlen' sets direction too
 278    */
 279   Direction dir = get_direction (me);
 280   if (!dir)
 281     {
 282       dir = get_default_dir (me);
 283       Directional_element_interface::set (me, dir);
 284     }
 285
 286   /*
 287     stems in unnatural (forced) direction should be shortened,
 288     according to [Roush & Gourlay]
 289    */
 290   if (( (int)chord_start_f (me))
 291       && (get_direction (me) != get_default_dir (me)))
 292     length_f -= shorten_f;
 293
 294
 295    Real st = head_positions (me)[dir] + dir * length_f;
 296
 297    bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
 298    if (!grace_b && !no_extend_b && dir * st < 0) // junkme?
 299       st = 0.0;
 300
 301   return st;
 302 }
 303
 304 /*
 305   Number of hooks on the flag, ie. the log of the duration.
 306  */
 307 int
 308 Stem::flag_i (Grob*me)
 309 {
 310   SCM s = me->get_grob_property ("duration-log");
 311   return (gh_number_p (s)) ? gh_scm2int (s) : 2;
 312 }
 313
 314 void
 315 Stem::position_noteheads (Grob*me)
 316 {
 317   if (!heads_i (me))
 318     return;
 319
 320   Link_array<Grob> heads =
 321     Pointer_group_interface__extract_elements (me, (Grob*)0, "heads");
 322
 323   heads.sort (compare_position);
 324   Direction dir =get_direction (me);
 325
 326   if (dir < 0)
 327     heads.reverse ();
 328
 329
 330   Grob *hed = support_head (me);
 331   Real w = hed->extent (hed, X_AXIS)[dir];
 332   for (int i=0; i < heads.size (); i++)
 333     {
 334       heads[i]->translate_axis (w - heads[i]->extent (heads[i], X_AXIS)[dir], X_AXIS);
 335     }
 336
 337   bool parity= true;            // todo: make me settable.
 338   int lastpos = int (Staff_symbol_referencer::position_f (heads[0]));
 339   for (int i=1; i < heads.size (); i ++)
 340     {
 341       Real p = Staff_symbol_referencer::position_f (heads[i]);
 342       int dy =abs (lastpos- (int)p);
 343
 344       if (dy <= 1)
 345         {
 346           if (parity)
 347             {
 348               Real l = heads[i]->extent (heads[i], X_AXIS).length ();
 349               heads[i]->translate_axis (l * get_direction (me), X_AXIS);
 350             }
 351           parity = !parity;
 352         }
 353       else
 354         parity = true;
 355
 356       lastpos = int (p);
 357     }
 358 }
 359
 360 MAKE_SCHEME_CALLBACK (Stem,before_line_breaking,1);
 361 SCM
 362 Stem::before_line_breaking (SCM smob)
 363 {
 364   Grob*me = unsmob_grob (smob);
 365   stem_end_position (me);       // ugh. Trigger direction calc.
 366   position_noteheads (me);
 367
 368   if (invisible_b (me))
 369     {
 370       me->remove_grob_property ("molecule-callback");
 371       // suicide ();
 372     }
 373
 374   set_spacing_hints (me);
 375   return SCM_UNSPECIFIED;
 376 }
 377
 378
 379 /*
 380   ugh.
 381   When in a beam with tuplet brackets, brew_mol is called early,
 382   caching a wrong value.
 383  */
 384 MAKE_SCHEME_CALLBACK (Stem, height, 2);
 385 SCM
 386 Stem::height (SCM smob, SCM ax)
 387 {
 388   Axis a = (Axis)gh_scm2int (ax);
 389   Grob * me = unsmob_grob (smob);
 390   assert (a == Y_AXIS);
 391
 392   SCM mol = me->get_uncached_molecule ();
 393   Interval iv;
 394   if (mol != SCM_EOL)
 395     iv = unsmob_molecule (mol)->extent (a);
 396   return ly_interval2scm (iv);
 397 }
 398
 399
 400 /**
 401    set stem directions for hinting the optical spacing correction.
 402
 403    Modifies DIR_LIST property of the Stem's Paper_column
 404
 405    TODO: more advanced: supply height of noteheads as well, for more advanced spacing possibilities
 406  */
 407 void
 408 Stem::set_spacing_hints (Grob*me)
 409 {
 410   if (!invisible_b (me))
 411     {
 412       SCM scmdir  = gh_int2scm (get_direction (me));
 413
 414       Item* item = dynamic_cast<Item*> (me);
 415       Item * col =  item->column_l ();
 416       SCM dirlist =col->get_grob_property ("dir-list");
 417       if (scm_sloppy_memq (scmdir, dirlist) == SCM_BOOL_F)
 418         {
 419           dirlist = gh_cons (scmdir, dirlist);
 420           col->set_grob_property ("dir-list", dirlist);
 421         }
 422     }
 423 }
 424
 425 Molecule
 426 Stem::flag (Grob*me)
 427 {
 428   String style;
 429   SCM st = me->get_grob_property ("flag-style");
 430   if (gh_string_p (st))
 431     {
 432       style = ly_scm2string (st);
 433     }
 434
 435   char c = (get_direction (me) == UP) ? 'u' : 'd';
 436   Molecule m = Font_interface::get_default_font (me)->find_by_name (String ("flags-") + to_str (c) +
 437                                       to_str (flag_i (me)));
 438   if (!style.empty_b ())
 439     m.add_molecule (Font_interface::get_default_font (me)->find_by_name (String ("flags-") + to_str (c) + style));
 440   return m;
 441 }
 442
 443 MAKE_SCHEME_CALLBACK (Stem,dim_callback,2);
 444 SCM
 445 Stem::dim_callback (SCM e, SCM ax)
 446 {
 447   Axis a = (Axis) gh_scm2int (ax);
 448   assert (a == X_AXIS);
 449   Grob *se = unsmob_grob (e);
 450   Interval r (0, 0);
 451   if (unsmob_grob (se->get_grob_property ("beam")) || abs (flag_i (se)) <= 2)
 452     ;   // TODO!
 453   else
 454     {
 455       r = flag (se).extent (X_AXIS);
 456     }
 457   return ly_interval2scm (r);
 458 }
 459
 460
 461
 462 MAKE_SCHEME_CALLBACK (Stem,brew_molecule,1);
 463
 464 SCM
 465 Stem::brew_molecule (SCM smob)
 466 {
 467   Grob*me = unsmob_grob (smob);
 468   Molecule mol;
 469   Direction d = get_direction (me);
 470
 471
 472   Real y1 = Staff_symbol_referencer::position_f (first_head (me));
 473   Real y2 = stem_end_position (me);
 474
 475   Interval stem_y (y1,y2);
 476   stem_y.unite (Interval (y2,y1));
 477
 478   Real dy = Staff_symbol_referencer::staff_space (me)/2.0;
 479   Real head_wid = 0;
 480
 481   if (Grob *hed = support_head (me))
 482     {
 483       Real slope =0.0;
 484
 485       Interval head_height = hed->extent (hed,Y_AXIS);
 486       Real y_attach = Note_head::stem_attachment_coordinate ( hed, Y_AXIS);
 487
 488       y_attach = head_height.linear_combination (y_attach);
 489       stem_y[Direction (-d)] += d * 2*y_attach;
 490     }
 491
 492
 493   if (!invisible_b (me))
 494     {
 495       Real stem_width = gh_scm2double (me->get_grob_property ("thickness")) * me->paper_l ()->get_var ("stafflinethickness");
 496       Molecule ss =Lookup::filledbox (Box (Interval (-stem_width/2, stem_width/2),
 497                                            Interval (stem_y[DOWN]*dy, stem_y[UP]*dy)));
 498       mol.add_molecule (ss);
 499     }
 500
 501   if (!beam_l (me) && abs (flag_i (me)) > 2)
 502     {
 503       Molecule fl = flag (me);
 504       fl.translate_axis (stem_y[d]*dy, Y_AXIS);
 505       mol.add_molecule (fl);
 506     }
 507
 508   return mol.smobbed_copy ();
 509 }
 510
 511 /*
 512   move the stem to right of the notehead if it is up.
 513  */
 514 MAKE_SCHEME_CALLBACK (Stem,off_callback,2);
 515 SCM
 516 Stem::off_callback (SCM element_smob, SCM)
 517 {
 518   Grob *me = unsmob_grob (element_smob);
 519
 520   Real r=0;
 521   if (Grob * f = first_head (me))
 522     {
 523       Interval head_wid = f->extent (f,X_AXIS);
 524
 525       Real attach =
 526         Note_head::stem_attachment_coordinate(f, X_AXIS);
 527
 528       Direction d = get_direction (me);
 529
 530       Real real_attach = head_wid.linear_combination (d * attach);
 531
 532       r = real_attach;
 533
 534       /*
 535         If not centered: correct for stem thickness.
 536        */
 537       if (attach)
 538         {
 539           Real rule_thick
 540             = gh_scm2double (me->get_grob_property ("thickness"))
 541             * me->paper_l ()->get_var ("stafflinethickness");
 542
 543
 544           r += - d * rule_thick * 0.5;
 545         }
 546     }
 547   return gh_double2scm (r);
 548 }
 549
 550
 551
 552 Grob*
 553 Stem::beam_l (Grob*me)
 554 {
 555   SCM b=  me->get_grob_property ("beam");
 556   return unsmob_grob (b);
 557 }
 558
 559
 560 // ugh still very long.
 561 Stem_info
 562 Stem::calc_stem_info (Grob*me)
 563 {
 564   Grob * beam = beam_l (me);
 565
 566   Direction beam_dir = Directional_element_interface::get (beam);
 567   if (!beam_dir)
 568     {
 569       programming_error ("Beam dir not set.");
 570       beam_dir = UP;
 571     }
 572
 573
 574   Real staff_space = Staff_symbol_referencer::staff_space (me);
 575   Real half_space = staff_space / 2;
 576   int multiplicity = Beam::get_multiplicity (beam);
 577
 578
 579   SCM space_proc = beam->get_grob_property ("space-function");
 580   SCM space = gh_call1 (space_proc, gh_int2scm (multiplicity));
 581   Real interbeam_f = gh_scm2double (space) * staff_space;
 582
 583   Real thick = gh_scm2double (beam->get_grob_property ("thickness"));
 584   Stem_info info;
 585   info.idealy_f_ = chord_start_f (me);
 586
 587   // for simplicity, we calculate as if dir == UP
 588   info.idealy_f_ *= beam_dir;
 589   SCM grace_prop = me->get_grob_property ("grace");
 590
 591   bool grace_b = to_boolean (grace_prop);
 592
 593   Array<Real> a;
 594   SCM s;
 595
 596   s = me->get_grob_property ("beamed-minimum-lengths");
 597   a.clear ();
 598   for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 599     a.push (gh_scm2double (gh_car (q)));
 600
 601
 602   Real minimum_length = a[multiplicity <? (a.size () - 1)] * staff_space;
 603   s = me->get_grob_property ("beamed-lengths");
 604
 605   a.clear ();
 606   for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 607     a.push (gh_scm2double (gh_car (q)));
 608
 609   Real stem_length =  a[multiplicity <? (a.size () - 1)] * staff_space;
 610
 611   if (!beam_dir || (beam_dir == Directional_element_interface::get (me)))
 612     /* normal beamed stem */
 613     {
 614       if (multiplicity)
 615         {
 616           info.idealy_f_ += thick + (multiplicity - 1) * interbeam_f;
 617         }
 618       info.miny_f_ = info.idealy_f_;
 619       info.maxy_f_ = INT_MAX;
 620
 621       info.idealy_f_ += stem_length;
 622       info.miny_f_ += minimum_length;
 623
 624       /*
 625         lowest beam of (UP) beam must never be lower than second staffline
 626
 627         Hmm, reference (Wanske?)
 628
 629         Although this (additional) rule is probably correct,
 630         I expect that highest beam (UP) should also never be lower
 631         than middle staffline, just as normal stems.
 632
 633       */
 634       bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
 635       if (!grace_b && !no_extend_b)
 636         {
 637           /* highest beam of (UP) beam must never be lower than middle
 638              staffline
 639              lowest beam of (UP) beam must never be lower than second staffline
 640            */
 641           info.miny_f_ =
 642             info.miny_f_ >? 0
 643             >? (- 2 * half_space - thick
 644                 + (multiplicity > 0) * thick
 645                 + interbeam_f * (multiplicity - 1));
 646         }
 647     }
 648   else
 649     /* knee */
 650     {
 651       info.idealy_f_ -= thick;
 652       info.maxy_f_ = info.idealy_f_;
 653       info.miny_f_ = -INT_MAX;
 654
 655       info.idealy_f_ -= stem_length;
 656       info.maxy_f_ -= minimum_length;
 657     }
 658
 659   info.idealy_f_ = (info.maxy_f_ <? info.idealy_f_) >? info.miny_f_;
 660
 661   s = beam->get_grob_property ("shorten");
 662   if (gh_number_p (s))
 663     info.idealy_f_ -= gh_scm2double (s);
 664
 665  Grob *common = me->common_refpoint (beam, Y_AXIS);
 666   Real interstaff_f = beam_dir *
 667  (me->relative_coordinate (common, Y_AXIS)
 668      - beam->relative_coordinate (common, Y_AXIS));
 669
 670   info.idealy_f_ += interstaff_f;
 671   info.miny_f_ += interstaff_f;
 672   info.maxy_f_ += interstaff_f ;
 673
 674   return info;
 675 }
 676
 677 bool
 678 Stem::has_interface (Grob*m)
 679 {
 680   return m && m->has_interface (ly_symbol2scm ("stem-interface"));
 681 }
 682
 683 void
 684 Stem::set_interface (Grob*me)
 685 {
 686   me->set_interface (ly_symbol2scm ("stem-interface"));
 687 }