lily/stem.cc

   1 /*
   2   stem.cc -- implement Stem
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996, 1997--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7     Jan Nieuwenhuizen <janneke@gnu.org>
   8
   9   TODO: This is way too hairy
  10 */
  11
  12 #include "dimension-cache.hh"
  13 #include "stem.hh"
  14 #include "debug.hh"
  15 #include "paper-def.hh"
  16 #include "note-head.hh"
  17 #include "lookup.hh"
  18 #include "molecule.hh"
  19 #include "paper-column.hh"
  20 #include "misc.hh"
  21 #include "beam.hh"
  22 #include "rest.hh"
  23 #include "group-interface.hh"
  24 #include "cross-staff.hh"
  25 #include "staff-symbol-referencer.hh"
  26
  27
  28 void
  29 Stem::set_beaming (int i,  Direction d )
  30 {
  31   SCM pair = get_elt_property ("beaming");
  32
  33   if (!gh_pair_p (pair))
  34     {
  35       pair = gh_cons (gh_int2scm (0),gh_int2scm (0));
  36       set_elt_property ("beaming", pair);
  37     }
  38   index_set_cell (pair, d, gh_int2scm (i));
  39 }
  40
  41 int
  42 Stem::beam_count (Direction d) const
  43 {
  44   SCM p=get_elt_property ("beaming");
  45   if (gh_pair_p (p))
  46     return gh_scm2int (index_cell (p,d));
  47   else
  48     return 0;
  49 }
  50
  51 Interval_t<int>
  52 Stem::head_positions () const
  53 {
  54   /*
  55     Mysterious FreeBSD fix by John Galbraith.  Somehow, the empty intervals
  56     trigger FP exceptions on FreeBSD.  Fix: do not return infinity
  57
  58    */
  59   if (!first_head ())
  60     {
  61       return Interval_t<int> (100,-100);
  62     }
  63
  64   Link_array<Note_head> head_l_arr =
  65     Group_interface__extract_elements (this, (Note_head*)0, "heads");
  66
  67   Interval_t<int> r;
  68   for (int i =0; i < head_l_arr.size (); i++)
  69     {
  70       Staff_symbol_referencer_interface si (head_l_arr[i]);
  71       int p = (int)si.position_f ();
  72       r[BIGGER] = r[BIGGER] >? p;
  73       r[SMALLER] = r[SMALLER] <? p;
  74     }
  75   return r;
  76 }
  77
  78 Real
  79 Stem::stem_begin_f () const
  80 {
  81   return yextent_[Direction(-get_direction ())];
  82 }
  83
  84 Real
  85 Stem::chord_start_f () const
  86 {
  87   return head_positions()[get_direction ()]
  88     * Staff_symbol_referencer_interface (this).staff_line_leading_f ()/2.0;
  89 }
  90
  91 Real
  92 Stem::stem_end_f () const
  93 {
  94   return yextent_[get_direction ()];
  95 }
  96
  97 void
  98 Stem::set_stemend (Real se)
  99 {
 100   // todo: margins
 101   if (get_direction () && get_direction () * head_positions()[get_direction ()] >= se*get_direction ())
 102     warning (_ ("Weird stem size; check for narrow beams"));
 103
 104
 105   yextent_[get_direction ()]  =  se;
 106   yextent_[Direction(-get_direction ())] = head_positions()[-get_direction ()];
 107 }
 108
 109 int
 110 Stem::type_i () const
 111 {
 112   return first_head () ?  first_head ()->balltype_i () : 2;
 113 }
 114
 115
 116
 117 /*
 118   Note head that determines hshift for upstems
 119  */
 120 Score_element*
 121 Stem::support_head ()const
 122 {
 123   SCM h = get_elt_property ("support-head");
 124   Score_element * nh = unsmob_element (h);
 125   if (nh)
 126     return nh;
 127   else
 128     return first_head ();
 129 }
 130
 131
 132 /*
 133   The note head which forms one end of the stem.
 134  */
 135 Note_head*
 136 Stem::first_head () const
 137 {
 138   const int inf = 1000000;
 139   int pos = -inf;
 140   Direction dir = get_direction ();
 141
 142
 143   Note_head *nh =0;
 144   for (SCM s = get_elt_property ("heads"); gh_pair_p (s); s = gh_cdr (s))
 145     {
 146       Note_head * n = dynamic_cast<Note_head*> (unsmob_element (gh_car (s)));
 147       Staff_symbol_referencer_interface si (n);
 148       int p = dir * int(si.position_f ());
 149       if (p > pos)
 150         {
 151           nh = n;
 152         }
 153     }
 154
 155   return nh;
 156 }
 157
 158 void
 159 Stem::add_head (Rhythmic_head *n)
 160 {
 161   n->set_elt_property ("stem", this->self_scm_);
 162   n->add_dependency (this);     // ?
 163
 164
 165   Group_interface gi (this);
 166   if (Note_head *nh = dynamic_cast<Note_head *> (n))
 167     gi.name_ = "heads";
 168   else
 169     gi.name_ = "rests";
 170
 171   gi.add_element (n);
 172 }
 173
 174 Stem::Stem ()
 175 {
 176   set_elt_property ("heads", SCM_EOL);
 177   set_elt_property ("rests", SCM_EOL);
 178 }
 179
 180 bool
 181 Stem::invisible_b () const
 182 {
 183   return !(first_head () && first_head()->balltype_i () >= 1);
 184 }
 185
 186 int
 187 Stem::get_center_distance (Direction d) const
 188 {
 189   int staff_center = 0;
 190   int distance = d*(head_positions()[d] - staff_center);
 191   return distance >? 0;
 192 }
 193
 194 Direction
 195 Stem::get_default_dir () const
 196 {
 197   int du = get_center_distance (UP);
 198   int dd = get_center_distance (DOWN);
 199
 200   if (sign (dd - du))
 201     return Direction (sign (dd -du));
 202
 203   return Direction (int(paper_l ()->get_var ("stem_default_neutral_direction")));
 204 }
 205
 206 void
 207 Stem::set_default_stemlen ()
 208 {
 209   Real length_f = 0.;
 210   SCM scm_len = get_elt_property("length");
 211   if (scm_len != SCM_UNDEFINED)
 212     {
 213       length_f = gh_scm2double (scm_len);
 214     }
 215   else
 216     length_f = paper_l ()->get_var ("stem_length0");
 217
 218   bool grace_b = get_elt_property ("grace") != SCM_UNDEFINED;
 219   String type_str = grace_b ? "grace_" : "";
 220
 221   Real shorten_f = paper_l ()->get_var (type_str + "forced_stem_shorten0");
 222
 223   /* URGURGURG
 224      'set-default-stemlen' sets direction too
 225    */
 226   if (!get_direction ())
 227     set_direction (get_default_dir ());
 228
 229   /*
 230     stems in unnatural (forced) direction should be shortened,
 231     according to [Roush & Gourlay]
 232    */
 233   if (((int)chord_start_f ())
 234       && (get_direction () != get_default_dir ()))
 235     length_f -= shorten_f;
 236
 237  if (flag_i () >= 5)
 238     length_f += 2.0;
 239   if (flag_i () >= 6)
 240     length_f += 1.0;
 241
 242   set_stemend ((get_direction () > 0) ? head_positions()[BIGGER] + length_f:
 243                head_positions()[SMALLER] - length_f);
 244
 245   bool no_extend_b = get_elt_property ("no-stem-extend") != SCM_UNDEFINED;
 246   if (!grace_b && !no_extend_b && (get_direction () * stem_end_f () < 0))
 247     set_stemend (0);
 248 }
 249
 250 int
 251 Stem::flag_i () const
 252 {
 253   SCM s = get_elt_property ("duration-log");
 254   return  (gh_number_p (s)) ? gh_scm2int (s) : 2;
 255 }
 256
 257 //xxx
 258 void
 259 Stem::set_default_extents ()
 260 {
 261   if (yextent_.empty_b ())
 262     set_default_stemlen ();
 263 }
 264
 265 void
 266 Stem::set_noteheads ()
 267 {
 268   if (!first_head ())
 269     return;
 270
 271   Link_array<Score_element> heads =
 272     Group_interface__extract_elements (this, (Score_element*)0, "heads");
 273
 274   heads.sort (compare_position);
 275   Direction dir =get_direction ();
 276
 277   if (dir < 0)
 278     heads.reverse ();
 279
 280
 281   Real w = support_head ()->extent (X_AXIS)[dir];
 282   for (int i=0; i < heads.size (); i++)
 283     {
 284       heads[i]->translate_axis (w - heads[i]->extent (X_AXIS)[dir], X_AXIS);
 285     }
 286
 287   bool parity= true;
 288   int lastpos = int (Staff_symbol_referencer_interface (heads[0]).position_f ());
 289   for (int i=1; i < heads.size (); i ++)
 290     {
 291       Real p = Staff_symbol_referencer_interface (heads[i]).position_f ();
 292       int dy =abs (lastpos- (int)p);
 293
 294       if (dy <= 1)
 295         {
 296           if (parity)
 297             {
 298               Real l  = heads[i]->extent (X_AXIS).length ();
 299               heads[i]->translate_axis (l * get_direction (), X_AXIS);
 300             }
 301           parity = !parity;
 302         }
 303       else
 304         parity = true;
 305
 306       lastpos = int (p);
 307     }
 308 }
 309
 310 void
 311 Stem::do_pre_processing ()
 312 {
 313   if (yextent_.empty_b ())
 314     set_default_extents ();
 315   set_noteheads ();
 316
 317   if (invisible_b ())
 318     {
 319       set_elt_property ("transparent", SCM_BOOL_T);
 320       set_empty (Y_AXIS);
 321       set_empty (X_AXIS);
 322     }
 323
 324   set_spacing_hints ();
 325 }
 326
 327
 328
 329 /**
 330    set stem directions for hinting the optical spacing correction.
 331
 332    Modifies DIR_LIST property of the Stem's Score_column
 333
 334    TODO: more advanced: supply height of noteheads as well, for more advanced spacing possibilities
 335  */
 336
 337 void
 338 Stem::set_spacing_hints ()
 339 {
 340   if (!invisible_b ())
 341     {
 342       SCM scmdir  = gh_int2scm (get_direction ());
 343       SCM dirlist = column_l ()->get_elt_property ("dir-list");
 344       if (dirlist == SCM_UNDEFINED)
 345         dirlist = SCM_EOL;
 346
 347       if (scm_sloppy_memq (scmdir, dirlist) == SCM_EOL)
 348         {
 349           dirlist = gh_cons (scmdir, dirlist);
 350           column_l ()->set_elt_property ("dir-list", dirlist);
 351         }
 352     }
 353 }
 354
 355 Molecule
 356 Stem::flag () const
 357 {
 358   String style;
 359   SCM st = get_elt_property ("style");
 360   if ( st != SCM_UNDEFINED)
 361     {
 362       style = ly_scm2string (st);
 363     }
 364
 365   char c = (get_direction () == UP) ? 'u' : 'd';
 366   Molecule m = lookup_l ()->afm_find (String ("flags-") + to_str (c) +
 367                                       to_str (flag_i ()));
 368   if (!style.empty_b ())
 369     m.add_molecule(lookup_l ()->afm_find (String ("flags-") + to_str (c) + style));
 370   return m;
 371 }
 372
 373 Interval
 374 Stem::dim_callback (Dimension_cache const* c)
 375 {
 376   Stem * s = dynamic_cast<Stem*> (c->element_l ());
 377
 378   Interval r (0, 0);
 379   if (s->get_elt_property ("beam") != SCM_UNDEFINED || abs (s->flag_i ()) <= 2)
 380     ;   // TODO!
 381   else
 382     {
 383       r = s->flag ().dim_.x ();
 384       r += s->note_delta_f ();
 385     }
 386   return r;
 387 }
 388
 389
 390 const Real ANGLE = 20* (2.0*M_PI/360.0); // ugh!
 391
 392 Molecule*
 393 Stem::do_brew_molecule_p () const
 394 {
 395   Molecule *mol_p =new Molecule;
 396   Interval stem_y = yextent_;
 397   Real dy = staff_symbol_referencer_interface (this)
 398     .staff_line_leading_f ()/2.0;
 399
 400   Real head_wid = 0;
 401   if (support_head ())
 402     head_wid = support_head ()->extent (X_AXIS).length ();
 403   stem_y[Direction(-get_direction ())] += get_direction () * head_wid * tan(ANGLE)/(2*dy);
 404
 405   if (!invisible_b ())
 406     {
 407       Real stem_width = paper_l ()->get_var ("stemthickness");
 408       Molecule ss =lookup_l ()->filledbox (Box (Interval (-stem_width/2, stem_width/2),
 409                                                  Interval (stem_y[DOWN]*dy, stem_y[UP]*dy)));
 410       mol_p->add_molecule (ss);
 411     }
 412
 413   if (!beam_l () && abs (flag_i ()) > 2)
 414     {
 415       Molecule fl = flag ();
 416       fl.translate_axis(stem_y[get_direction ()]*dy, Y_AXIS);
 417       mol_p->add_molecule (fl);
 418     }
 419
 420   if (first_head ())
 421     {
 422       mol_p->translate_axis (note_delta_f (), X_AXIS);
 423     }
 424   return mol_p;
 425 }
 426
 427 Real
 428 Stem::note_delta_f () const
 429 {
 430   Real r=0;
 431   if (first_head ())
 432     {
 433       Interval head_wid(0,  first_head()->extent (X_AXIS).length ());
 434          Real rule_thick = paper_l ()->get_var ("stemthickness");
 435
 436       Interval stem_wid(-rule_thick/2, rule_thick/2);
 437       if (get_direction () == CENTER)
 438         r = head_wid.center ();
 439       else
 440         r = head_wid[get_direction ()] - stem_wid[get_direction ()];
 441     }
 442   return r;
 443 }
 444
 445 Real
 446 Stem::hpos_f () const
 447 {
 448   return note_delta_f () + Item::hpos_f ();
 449 }
 450
 451
 452 Beam*
 453 Stem::beam_l ()const
 454 {
 455   SCM b=  get_elt_property ("beam");
 456   return dynamic_cast<Beam*> (unsmob_element (b));
 457 }
 458
 459
 460 // ugh still very long.
 461 Stem_info
 462 Stem::calc_stem_info () const
 463 {
 464   assert (beam_l ());
 465
 466   Direction beam_dir = beam_l ()->get_direction ();
 467   if (!beam_dir)
 468     {
 469       programming_error ("Beam dir not set.");
 470       beam_dir = UP;
 471     }
 472
 473   Stem_info info;
 474   Real internote_f
 475      = staff_symbol_referencer_interface (this).staff_line_leading_f ()/2;
 476    Real interbeam_f = paper_l ()->interbeam_f (beam_l ()->get_multiplicity ());
 477   Real beam_f = gh_scm2double (beam_l ()->get_elt_property ("beam-thickness"));
 478
 479   info.idealy_f_ = chord_start_f ();
 480
 481   // for simplicity, we calculate as if dir == UP
 482   info.idealy_f_ *= beam_dir;
 483
 484   bool grace_b = get_elt_property ("grace") != SCM_UNDEFINED;
 485   bool no_extend_b = get_elt_property ("no-stem-extend") != SCM_UNDEFINED;
 486
 487   int stem_max = (int)rint(paper_l ()->get_var ("stem_max"));
 488   String type_str = grace_b ? "grace_" : "";
 489   Real min_stem_f = paper_l ()->get_var (type_str + "minimum_stem_length"
 490     + to_str (beam_l ()->get_multiplicity () <? stem_max)) * internote_f;
 491   Real stem_f = paper_l ()->get_var (type_str + "stem_length"
 492     + to_str (beam_l ()->get_multiplicity () <? stem_max)) * internote_f;
 493
 494   if (!beam_dir || (beam_dir == get_direction ()))
 495     /* normal beamed stem */
 496     {
 497       if (beam_l ()->get_multiplicity ())
 498         {
 499           info.idealy_f_ += beam_f;
 500           info.idealy_f_ += (beam_l ()->get_multiplicity () - 1) * interbeam_f;
 501         }
 502       info.miny_f_ = info.idealy_f_;
 503       info.maxy_f_ = INT_MAX;
 504
 505       info.idealy_f_ += stem_f;
 506       info.miny_f_ += min_stem_f;
 507
 508       /*
 509         lowest beam of (UP) beam must never be lower than second staffline
 510
 511         Hmm, reference (Wanske?)
 512
 513         Although this (additional) rule is probably correct,
 514         I expect that highest beam (UP) should also never be lower
 515         than middle staffline, just as normal stems.
 516
 517       */
 518       if (!grace_b && !no_extend_b)
 519         {
 520           //highest beam of (UP) beam must never be lower than middle staffline
 521           info.miny_f_ = info.miny_f_ >? 0;
 522           //lowest beam of (UP) beam must never be lower than second staffline
 523           info.miny_f_ = info.miny_f_ >? (- 2 * internote_f - beam_f
 524                                 + (beam_l ()->get_multiplicity () > 0) * beam_f + interbeam_f * (beam_l ()->get_multiplicity () - 1));
 525         }
 526     }
 527   else
 528     /* knee */
 529     {
 530       info.idealy_f_ -= beam_f;
 531       info.maxy_f_ = info.idealy_f_;
 532       info.miny_f_ = -INT_MAX;
 533
 534       info.idealy_f_ -= stem_f;
 535       info.maxy_f_ -= min_stem_f;
 536     }
 537
 538   info.idealy_f_ = info.maxy_f_ <? info.idealy_f_;
 539   info.idealy_f_ = info.miny_f_ >? info.idealy_f_;
 540
 541   Real interstaff_f = calc_interstaff_dist (this, beam_l ());
 542
 543   SCM s = beam_l ()->get_elt_property ("shorten");
 544   if (s != SCM_UNDEFINED)
 545     info.idealy_f_ -= gh_double2scm (s);
 546
 547   info.idealy_f_ += interstaff_f * beam_dir;
 548   info.miny_f_ += interstaff_f * beam_dir;
 549   info.maxy_f_ += interstaff_f * beam_dir;
 550
 551   return info;
 552 }
 553