lily/stem.cc

   1 /*
   2   stem.cc -- implement Stem
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996--2000 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 "cross-staff.hh"
  28 #include "staff-symbol-referencer.hh"
  29 #include "spanner.hh"
  30
  31
  32 void
  33 Stem::set_beaming (Grob*me ,int i,  Direction d )
  34 {
  35   SCM pair = me->get_grob_property ("beaming");
  36
  37   if (!gh_pair_p (pair))
  38     {
  39       pair = gh_cons (gh_int2scm (0),gh_int2scm (0));
  40       me->      set_grob_property ("beaming", pair);
  41     }
  42   index_set_cell (pair, d, gh_int2scm (i));
  43 }
  44
  45 int
  46 Stem::beam_count (Grob*me,Direction d)
  47 {
  48   SCM p=me->get_grob_property ("beaming");
  49   if (gh_pair_p (p))
  50     return gh_scm2int (index_cell (p,d));
  51   else
  52     return 0;
  53 }
  54
  55 Interval
  56 Stem::head_positions (Grob*me)
  57 {
  58   if (!heads_i (me))
  59     {
  60       Interval iv;
  61       return iv;
  62     }
  63
  64   Drul_array<Grob*> e (extremal_heads (me));
  65
  66   return Interval (Staff_symbol_referencer::position_f (e[DOWN]),
  67                    Staff_symbol_referencer::position_f ( e[UP]));
  68 }
  69
  70
  71 Real
  72 Stem::chord_start_f (Grob*me)
  73 {
  74   return head_positions(me)[get_direction (me)]
  75     * Staff_symbol_referencer::staff_space (me)/2.0;
  76 }
  77
  78 Real
  79 Stem::stem_end_position (Grob*me)
  80 {
  81   SCM p =me->get_grob_property ("stem-end-position");
  82   Real pos;
  83   if (!gh_number_p (p))
  84     {
  85
  86       pos = get_default_stem_end_position (me);
  87       me->set_grob_property ("stem-end-position", gh_double2scm (pos));
  88     }
  89   else
  90     pos = gh_scm2double (p);
  91
  92   return pos;
  93 }
  94
  95 Direction
  96 Stem::get_direction (Grob*me)
  97 {
  98   Direction d = Directional_element_interface::get (me);
  99
 100   if (!d)
 101     {
 102        d = get_default_dir (me);
 103        // urg, AAARGH!
 104        Directional_element_interface::set (me, d);
 105     }
 106   return d ;
 107 }
 108
 109
 110 void
 111 Stem::set_stemend (Grob*me, Real se)
 112 {
 113   // todo: margins
 114   Direction d= get_direction (me);
 115
 116   if (d && d * head_positions(me)[get_direction (me)] >= se*d)
 117     warning (_ ("Weird stem size; check for narrow beams"));
 118
 119   me->set_grob_property ("stem-end-position", gh_double2scm (se));
 120 }
 121
 122 int
 123 Stem::type_i (Grob*me)
 124 {
 125   return first_head (me) ?  Rhythmic_head::balltype_i (first_head (me)) : 2;
 126 }
 127
 128 /*
 129   Note head that determines hshift for upstems
 130  */
 131 Grob*
 132 Stem::support_head (Grob*me)
 133 {
 134   SCM h = me->get_grob_property ("support-head");
 135   Grob * nh = unsmob_grob (h);
 136   if (nh)
 137     return nh;
 138   else if (heads_i (me) == 1)
 139     {
 140       /*
 141         UGH.
 142        */
 143
 144       return unsmob_grob (gh_car (me->get_grob_property ("heads")));
 145     }
 146   else
 147     return first_head (me);
 148 }
 149
 150
 151 int
 152 Stem::heads_i (Grob*me)
 153 {
 154   return  Pointer_group_interface::count (me, "heads");
 155 }
 156
 157 /*
 158   The note head which forms one end of the stem.
 159  */
 160 Grob*
 161 Stem::first_head (Grob*me)
 162 {
 163   return extremal_heads (me)[-get_direction (me)];
 164 }
 165
 166 /*
 167   START is part where stem reaches `last' head.
 168  */
 169 Drul_array<Grob*>
 170 Stem::extremal_heads (Grob*me)
 171 {
 172   const int inf = 1000000;
 173   Drul_array<int> extpos;
 174   extpos[DOWN] = inf;
 175   extpos[UP] = -inf;
 176
 177   Drul_array<Grob *> exthead;
 178   exthead[LEFT] = exthead[RIGHT] =0;
 179
 180   for (SCM s = me->get_grob_property ("heads"); gh_pair_p (s); s = gh_cdr (s))
 181     {
 182       Grob * n = unsmob_grob (gh_car (s));
 183
 184
 185       int p = int(Staff_symbol_referencer::position_f (n));
 186
 187       Direction d = LEFT;
 188       do {
 189       if (d* p > d* extpos[d])
 190         {
 191           exthead[d] = n;
 192           extpos[d] = p;
 193         }
 194       } while (flip (&d) != DOWN);
 195     }
 196
 197   return exthead;
 198 }
 199
 200 void
 201 Stem::add_head (Grob*me, Grob *n)
 202 {
 203   n->set_grob_property ("stem", me->self_scm ());
 204   n->add_dependency (me);
 205
 206   if (Note_head::has_interface (n))
 207     {
 208       Pointer_group_interface::add_element (me, "heads",n);
 209     }
 210   else
 211     {
 212       n->set_grob_property ("rest", n->self_scm ());
 213     }
 214 }
 215
 216 bool
 217 Stem::invisible_b (Grob*me)
 218 {
 219   return !(heads_i (me) && Rhythmic_head::balltype_i (support_head (me)) >= 1);
 220 }
 221
 222 int
 223 Stem::get_center_distance (Grob*me, Direction d)
 224 {
 225   int staff_center = 0;
 226   int distance = (int) (d*(head_positions(me)[d] - staff_center));
 227   return distance >? 0;
 228 }
 229
 230 Direction
 231 Stem::get_default_dir (Grob*me)
 232 {
 233   int du = get_center_distance (me,UP);
 234   int dd = get_center_distance (me,DOWN);
 235
 236   if (sign (dd - du))
 237     return Direction (sign (dd -du));
 238
 239   return to_dir (me->get_grob_property ("default-neutral-direction"));
 240 }
 241
 242 Real
 243 Stem::get_default_stem_end_position (Grob*me)
 244 {
 245   bool grace_b = to_boolean (me->get_grob_property ("grace"));
 246   SCM s;
 247   Array<Real> a;
 248
 249   Real length_f = 0.;
 250   SCM scm_len = me->get_grob_property("length");
 251   if (gh_number_p (scm_len))
 252     {
 253       length_f = gh_scm2double (scm_len);
 254     }
 255   else
 256     {
 257       s = me->get_grob_property("lengths");
 258       for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 259         a.push (gh_scm2double (gh_car (q)));
 260
 261       // stem uses half-spaces
 262       length_f = a[((flag_i (me) - 2) >? 0) <? (a.size () - 1)] * 2;
 263     }
 264
 265
 266   a.clear ();
 267   s = me->get_grob_property ("stem-shorten");
 268   for (SCM q = s; gh_pair_p (q); q = gh_cdr (q))
 269     a.push (gh_scm2double (gh_car (q)));
 270
 271
 272   // stem uses half-spaces
 273
 274   // fixme: use gh_list_ref () iso. array[]
 275   Real shorten_f = a[((flag_i (me) - 2) >? 0) <? (a.size () - 1)] * 2;
 276
 277   /* URGURGURG
 278      'set-default-stemlen' sets direction too
 279    */
 280   Direction dir = get_direction (me);
 281   if (!dir)
 282     {
 283       dir = get_default_dir (me);
 284       Directional_element_interface::set (me, dir);
 285     }
 286
 287   /*
 288     stems in unnatural (forced) direction should be shortened,
 289     according to [Roush & Gourlay]
 290    */
 291   if (((int)chord_start_f (me))
 292       && (get_direction (me) != get_default_dir (me)))
 293     length_f -= shorten_f;
 294
 295
 296    Real st = head_positions(me)[dir] + dir * length_f;
 297
 298    bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
 299    if (!grace_b && !no_extend_b && dir * st < 0) // junkme?
 300       st = 0.0;
 301
 302   return st;
 303 }
 304
 305 /*
 306   Number of hooks on the flag, ie. the log of the duration.
 307  */
 308 int
 309 Stem::flag_i (Grob*me)
 310 {
 311   SCM s = me->get_grob_property ("duration-log");
 312   return  (gh_number_p (s)) ? gh_scm2int (s) : 2;
 313 }
 314
 315 void
 316 Stem::position_noteheads (Grob*me)
 317 {
 318   if (!heads_i (me))
 319     return;
 320
 321   Link_array<Grob> heads =
 322     Pointer_group_interface__extract_elements (me, (Grob*)0, "heads");
 323
 324   heads.sort (compare_position);
 325   Direction dir =get_direction (me);
 326
 327   if (dir < 0)
 328     heads.reverse ();
 329
 330
 331   Grob *hed = support_head (me);
 332   Real w = hed->extent (hed, X_AXIS)[dir];
 333   for (int i=0; i < heads.size (); i++)
 334     {
 335       heads[i]->translate_axis (w - heads[i]->extent (heads[i], X_AXIS)[dir], X_AXIS);
 336     }
 337
 338   bool parity= true;            // todo: make me settable.
 339   int lastpos = int (Staff_symbol_referencer::position_f (heads[0]));
 340   for (int i=1; i < heads.size (); i ++)
 341     {
 342       Real p = Staff_symbol_referencer::position_f (heads[i]);
 343       int dy =abs (lastpos- (int)p);
 344
 345       if (dy <= 1)
 346         {
 347           if (parity)
 348             {
 349               Real l = heads[i]->extent (heads[i], X_AXIS).length ();
 350               heads[i]->translate_axis (l * get_direction (me), X_AXIS);
 351             }
 352           parity = !parity;
 353         }
 354       else
 355         parity = true;
 356
 357       lastpos = int (p);
 358     }
 359 }
 360
 361 MAKE_SCHEME_CALLBACK(Stem,before_line_breaking,1);
 362 SCM
 363 Stem::before_line_breaking (SCM smob)
 364 {
 365   Grob*me = unsmob_grob (smob);
 366   stem_end_position (me);       // ugh. Trigger direction calc.
 367   position_noteheads (me);
 368
 369   if (invisible_b (me))
 370     {
 371       me->remove_grob_property ("molecule-callback");
 372       // suicide();
 373     }
 374
 375   set_spacing_hints (me);
 376   return SCM_UNSPECIFIED;
 377 }
 378
 379
 380 /*
 381   ugh.
 382   When in a beam with tuplet brackets, brew_mol is called early,
 383   caching a wrong value.
 384  */
 385 MAKE_SCHEME_CALLBACK (Stem, height, 2);
 386 SCM
 387 Stem::height (SCM smob, SCM ax)
 388 {
 389   Axis a = (Axis)gh_scm2int (ax);
 390   Grob * me = unsmob_grob (smob);
 391   assert ( a == Y_AXIS);
 392
 393   SCM mol = me->get_uncached_molecule ();
 394   Interval iv;
 395   if (mol != SCM_EOL)
 396     iv = unsmob_molecule (mol)->extent (a);
 397   return ly_interval2scm (iv);
 398 }
 399
 400
 401 /**
 402    set stem directions for hinting the optical spacing correction.
 403
 404    Modifies DIR_LIST property of the Stem's Paper_column
 405
 406    TODO: more advanced: supply height of noteheads as well, for more advanced spacing possibilities
 407  */
 408 void
 409 Stem::set_spacing_hints (Grob*me)
 410 {
 411   if (!invisible_b (me))
 412     {
 413       SCM scmdir  = gh_int2scm (get_direction (me));
 414
 415       Item* item = dynamic_cast<Item*> (me);
 416       Item * col =  item->column_l ();
 417       SCM dirlist =col->get_grob_property ("dir-list");
 418       if (scm_sloppy_memq (scmdir, dirlist) == SCM_BOOL_F)
 419         {
 420           dirlist = gh_cons (scmdir, dirlist);
 421           col->set_grob_property ("dir-list", dirlist);
 422         }
 423     }
 424 }
 425
 426 Molecule
 427 Stem::flag (Grob*me)
 428 {
 429   String style;
 430   SCM st = me->get_grob_property ("flag-style");
 431   if ( gh_string_p (st))
 432     {
 433       style = ly_scm2string (st);
 434     }
 435
 436   char c = (get_direction (me) == UP) ? 'u' : 'd';
 437   Molecule m = Font_interface::get_default_font (me)->find_by_name (String ("flags-") + to_str (c) +
 438                                       to_str (flag_i (me)));
 439   if (!style.empty_b ())
 440     m.add_molecule(Font_interface::get_default_font (me)->find_by_name (String ("flags-") + to_str (c) + style));
 441   return m;
 442 }
 443
 444 MAKE_SCHEME_CALLBACK(Stem,dim_callback,2);
 445 SCM
 446 Stem::dim_callback (SCM e, SCM ax)
 447 {
 448   Axis a = (Axis) gh_scm2int (ax);
 449   assert (a == X_AXIS);
 450   Grob *se = unsmob_grob (e);
 451   Interval r (0, 0);
 452   if (unsmob_grob (se->get_grob_property ("beam")) || abs (flag_i (se)) <= 2)
 453     ;   // TODO!
 454   else
 455     {
 456       r = flag (se).extent (X_AXIS);
 457     }
 458   return ly_interval2scm ( r);
 459 }
 460
 461
 462 const Real ANGLE = 20* (2.0*M_PI/360.0); // ugh! Should be settable.
 463
 464
 465 MAKE_SCHEME_CALLBACK(Stem,brew_molecule,1);
 466
 467 SCM
 468 Stem::brew_molecule (SCM smob)
 469 {
 470   Grob*me = unsmob_grob (smob);
 471   Molecule mol;
 472   Direction d = get_direction (me);
 473
 474
 475   Real y1 = Staff_symbol_referencer::position_f (first_head (me));
 476   Real y2 = stem_end_position (me);
 477
 478   Interval stem_y(y1,y2);
 479   stem_y.unite (Interval (y2,y1));
 480
 481   Real dy = Staff_symbol_referencer::staff_space (me)/2.0;
 482   Real head_wid = 0;
 483
 484   if (Grob *hed = support_head (me))
 485     head_wid = hed->extent (hed,X_AXIS).length ();
 486   stem_y[Direction(-d)] += d * head_wid * tan(ANGLE)/(2*dy);
 487
 488   if (!invisible_b (me))
 489     {
 490       Real stem_width = gh_scm2double (me->get_grob_property ("thickness")) * me->paper_l ()->get_var ("stafflinethickness");
 491       Molecule ss =Lookup::filledbox (Box (Interval (-stem_width/2, stem_width/2),
 492                                            Interval (stem_y[DOWN]*dy, stem_y[UP]*dy)));
 493       mol.add_molecule (ss);
 494     }
 495
 496   if (!beam_l (me) && abs (flag_i (me)) > 2)
 497     {
 498       Molecule fl = flag (me);
 499       fl.translate_axis(stem_y[d]*dy, Y_AXIS);
 500       mol.add_molecule (fl);
 501     }
 502
 503   return mol.smobbed_copy ();
 504 }
 505
 506 MAKE_SCHEME_CALLBACK(Stem,off_callback,2);
 507 SCM
 508 Stem::off_callback (SCM element_smob, SCM )
 509 {
 510   Grob *me = unsmob_grob (element_smob);
 511
 512   Real r=0;
 513   if (Grob * f = first_head (me))
 514     {
 515       Interval head_wid(0, f->extent (f,X_AXIS).length ());
 516
 517       if (to_boolean (me->get_grob_property ("stem-centered")))
 518         return gh_double2scm ( head_wid.center ());
 519
 520       Real rule_thick = gh_scm2double (me->get_grob_property ("thickness")) * me->paper_l ()->get_var ("stafflinethickness");
 521       Direction d = get_direction (me);
 522       r = head_wid[d] - d * rule_thick ;
 523     }
 524   return gh_double2scm (r);
 525 }
 526
 527
 528
 529 Grob*
 530 Stem::beam_l (Grob*me)
 531 {
 532   SCM b=  me->get_grob_property ("beam");
 533   return unsmob_grob (b);
 534 }
 535
 536
 537 // ugh still very long.
 538 Stem_info
 539 Stem::calc_stem_info (Grob*me)
 540 {
 541   Grob * beam = beam_l (me);
 542
 543   Direction beam_dir = Directional_element_interface::get (beam);
 544   if (!beam_dir)
 545     {
 546       programming_error ("Beam dir not set.");
 547       beam_dir = UP;
 548     }
 549
 550
 551   Real staff_space = Staff_symbol_referencer::staff_space (me);
 552   Real half_space = staff_space / 2;
 553   int multiplicity = Beam::get_multiplicity (beam);
 554
 555
 556   SCM space_proc = beam->get_grob_property ("space-function");
 557   SCM space = gh_call1 (space_proc, gh_int2scm (multiplicity));
 558   Real interbeam_f = gh_scm2double (space) * staff_space;
 559
 560   Real thick = gh_scm2double (beam->get_grob_property ("thickness"));
 561   Stem_info info;
 562   info.idealy_f_ = chord_start_f (me);
 563
 564   // for simplicity, we calculate as if dir == UP
 565   info.idealy_f_ *= beam_dir;
 566   SCM grace_prop = me->get_grob_property ("grace");
 567
 568   bool grace_b = to_boolean (grace_prop);
 569
 570   Array<Real> a;
 571   SCM s;
 572
 573   s = me->get_grob_property("beamed-minimum-lengths");
 574   a.clear ();
 575   for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 576     a.push (gh_scm2double (gh_car (q)));
 577
 578
 579   Real minimum_length = a[multiplicity <? (a.size () - 1)] * staff_space;
 580   s = me->get_grob_property ("beamed-lengths");
 581
 582   a.clear();
 583   for (SCM q = s; q != SCM_EOL; q = gh_cdr (q))
 584     a.push (gh_scm2double (gh_car (q)));
 585
 586   Real stem_length =  a[multiplicity <? (a.size () - 1)] * staff_space;
 587
 588   if (!beam_dir || (beam_dir == Directional_element_interface::get (me)))
 589     /* normal beamed stem */
 590     {
 591       if (multiplicity)
 592         {
 593           info.idealy_f_ += thick + (multiplicity - 1) * interbeam_f;
 594         }
 595       info.miny_f_ = info.idealy_f_;
 596       info.maxy_f_ = INT_MAX;
 597
 598       info.idealy_f_ += stem_length;
 599       info.miny_f_ += minimum_length;
 600
 601       /*
 602         lowest beam of (UP) beam must never be lower than second staffline
 603
 604         Hmm, reference (Wanske?)
 605
 606         Although this (additional) rule is probably correct,
 607         I expect that highest beam (UP) should also never be lower
 608         than middle staffline, just as normal stems.
 609
 610       */
 611       bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
 612       if (!grace_b && !no_extend_b)
 613         {
 614           /* highest beam of (UP) beam must never be lower than middle
 615              staffline
 616              lowest beam of (UP) beam must never be lower than second staffline
 617            */
 618           info.miny_f_ =
 619             info.miny_f_ >? 0
 620             >? (- 2 * half_space - thick
 621                 + (multiplicity > 0) * thick
 622                 + interbeam_f * (multiplicity - 1));
 623         }
 624     }
 625   else
 626     /* knee */
 627     {
 628       info.idealy_f_ -= thick;
 629       info.maxy_f_ = info.idealy_f_;
 630       info.miny_f_ = -INT_MAX;
 631
 632       info.idealy_f_ -= stem_length;
 633       info.maxy_f_ -= minimum_length;
 634     }
 635
 636   info.idealy_f_ = (info.maxy_f_ <? info.idealy_f_) >? info.miny_f_;
 637
 638   s = beam->get_grob_property ("shorten");
 639   if (gh_number_p (s))
 640     info.idealy_f_ -= gh_scm2double (s);
 641
 642   Real interstaff_f = -beam_dir* calc_interstaff_dist (dynamic_cast<Item*> (me), dynamic_cast<Spanner*> (beam));
 643
 644   info.idealy_f_ += interstaff_f;
 645   info.miny_f_ += interstaff_f;
 646   info.maxy_f_ += interstaff_f ;
 647
 648   return info;
 649 }
 650
 651 bool
 652 Stem::has_interface (Grob*m)
 653 {
 654   return m && m->has_interface (ly_symbol2scm ("stem-interface"));
 655 }
 656
 657 void
 658 Stem::set_interface (Grob*me)
 659 {
 660   me->set_interface (ly_symbol2scm ("stem-interface"));
 661 }