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
   8   TODO: This is way too hairy
   9 */
  10
  11 #include "stem.hh"
  12 #include "debug.hh"
  13 #include "paper-def.hh"
  14 #include "note-head.hh"
  15 #include "lookup.hh"
  16 #include "molecule.hh"
  17 #include "paper-column.hh"
  18 #include "misc.hh"
  19 #include "beam.hh"
  20 #include "rest.hh"
  21
  22 void
  23 Stem::set_direction (Direction d)
  24 {
  25   if  (!dir_)
  26     warning ("Stem direction set already!");
  27
  28   dir_ = d;
  29
  30   /*
  31     todo
  32   */
  33 }
  34
  35 Stem::Stem ()
  36 {
  37   beams_i_drul_[LEFT] = beams_i_drul_[RIGHT] = -1;
  38   yextent_drul_[DOWN] = yextent_drul_[UP] = 0;
  39   flag_i_ = 2;
  40   dir_ = CENTER;
  41   beam_l_ = 0;
  42 }
  43
  44 Interval_t<int>
  45 Stem::head_positions () const
  46 {
  47   /*
  48     Mysterious FreeBSD fix by John Galbraith.  Somehow, the empty intervals
  49     trigger FP exceptions on FreeBSD.  Fix: do not return infinity
  50
  51    */
  52   if (!head_l_arr_.size ())
  53     {
  54       return Interval_t<int> (100,-100);
  55     }
  56
  57   Interval_t<int> r;
  58   for (int i =0; i < head_l_arr_.size (); i++)
  59     {
  60       int p = head_l_arr_[i]->position_i_;
  61       r[BIGGER] = r[BIGGER] >? p;
  62       r[SMALLER] = r[SMALLER] <? p;
  63     }
  64   return r;
  65 }
  66
  67 void
  68 Stem::do_print () const
  69 {
  70 #ifndef NPRINT
  71   DOUT << "flag "<< flag_i_;
  72   if (beam_l_)
  73     DOUT << "beamed";
  74 #endif
  75 }
  76
  77 Real
  78 Stem::stem_length_f () const
  79 {
  80   return yextent_drul_[UP]-yextent_drul_[DOWN] ;
  81 }
  82
  83 Real
  84 Stem::stem_begin_f () const
  85 {
  86   return yextent_drul_[Direction(-dir_)];
  87 }
  88
  89 Real
  90 Stem::chord_start_f () const
  91 {
  92   return head_positions()[dir_] * staff_line_leading_f ()/2.0;
  93 }
  94
  95 Real
  96 Stem::stem_end_f () const
  97 {
  98   return yextent_drul_[dir_];
  99 }
 100
 101 void
 102 Stem::set_stemend (Real se)
 103 {
 104   // todo: margins
 105   if (dir_ && dir_ * head_positions()[dir_] >= se*dir_)
 106     warning (_ ("weird stem size; check for narrow beams"));
 107
 108
 109   yextent_drul_[dir_]  =  se;
 110   yextent_drul_[Direction(-dir_)] = head_positions()[-dir_];
 111 }
 112
 113 int
 114 Stem::type_i () const
 115 {
 116   return head_l_arr_[0]->balltype_i_;
 117 }
 118
 119 void
 120 Stem::add_head (Rhythmic_head *n)
 121 {
 122   n->stem_l_ = this;
 123   n->add_dependency (this);     // ?
 124   if (Note_head *nh = dynamic_cast<Note_head *> (n))
 125     {
 126       head_l_arr_.push (nh);
 127     }
 128   else if (Rest *r = dynamic_cast<Rest *> (n))
 129     {
 130       rest_l_arr_.push (r);
 131     }
 132 }
 133
 134 bool
 135 Stem::invisible_b () const
 136 {
 137   return (!head_l_arr_.size () ||
 138     head_l_arr_[0]->balltype_i_ <= 0);
 139 }
 140
 141 int
 142 Stem::get_center_distance (Direction d) const
 143 {
 144   int staff_center = 0;
 145   int distance = d*(head_positions()[d] - staff_center);
 146   return distance >? 0;
 147 }
 148
 149 Direction
 150 Stem::get_default_dir () const
 151 {
 152   int du = get_center_distance (UP);
 153   int dd = get_center_distance (DOWN);
 154
 155   if (sign (dd - du))
 156     return Direction (sign (dd -du));
 157
 158   return Direction (int(paper_l ()->get_var ("stem_default_neutral_direction")));
 159 }
 160
 161 Direction
 162 Stem::get_dir () const
 163 {
 164   return dir_;
 165 }
 166
 167
 168 void
 169 Stem::set_default_stemlen ()
 170 {
 171   Real length_f = 0.;
 172   SCM scm_len = get_elt_property(length_scm_sym);
 173   if (scm_len != SCM_BOOL_F)
 174     {
 175       length_f = gh_scm2double (SCM_CDR(scm_len));
 176     }
 177   else
 178     length_f = paper_l ()->get_var ("stem_length0");
 179
 180   bool grace_b = get_elt_property (grace_scm_sym) != SCM_BOOL_F;
 181   String type_str = grace_b ? "grace_" : "";
 182
 183   Real shorten_f = paper_l ()->get_var (type_str + "forced_stem_shorten0");
 184
 185   if (!dir_)
 186     dir_ = get_default_dir ();
 187
 188   /*
 189     stems in unnatural (forced) direction should be shortened,
 190     according to [Roush & Gourlay]
 191    */
 192   if (((int)chord_start_f ())
 193       && (dir_ != get_default_dir ()))
 194     length_f -= shorten_f;
 195
 196   if (flag_i_ >= 5)
 197     length_f += 2.0;
 198   if (flag_i_ >= 6)
 199     length_f += 1.0;
 200
 201   set_stemend ((dir_ > 0) ? head_positions()[BIGGER] + length_f:
 202                head_positions()[SMALLER] - length_f);
 203
 204   if (!grace_b && (dir_ * stem_end_f () < 0))
 205     set_stemend (0);
 206 }
 207
 208 //xxx
 209 void
 210 Stem::set_default_extents ()
 211 {
 212   if (!stem_length_f ())
 213     set_default_stemlen ();
 214
 215 }
 216
 217 void
 218 Stem::set_noteheads ()
 219 {
 220   if (!head_l_arr_.size ())
 221     return;
 222   head_l_arr_.sort (Note_head::compare);
 223   if (dir_ < 0)
 224     head_l_arr_.reverse ();
 225
 226   Note_head * beginhead =   head_l_arr_[0];
 227   beginhead->set_elt_property (extremal_scm_sym, SCM_BOOL_T);
 228   if  (beginhead !=   head_l_arr_.top ())
 229     head_l_arr_.top ()->set_elt_property (extremal_scm_sym, SCM_BOOL_T);
 230
 231   int parity=1;
 232   int lastpos = beginhead->position_i_;
 233   for (int i=1; i < head_l_arr_.size (); i ++)
 234     {
 235       int dy =abs (lastpos- head_l_arr_[i]->position_i_);
 236
 237       if (dy <= 1)
 238         {
 239           if (parity)
 240             head_l_arr_[i]->flip_around_stem (dir_);
 241           parity = !parity;
 242         }
 243       else
 244         parity = 1;
 245       lastpos = head_l_arr_[i]->position_i_;
 246     }
 247 }
 248
 249 void
 250 Stem::do_pre_processing ()
 251 {
 252   if (yextent_drul_[DOWN]== yextent_drul_[UP])
 253     set_default_extents ();
 254   set_noteheads ();
 255
 256   if (invisible_b ())
 257     {
 258       set_elt_property (transparent_scm_sym, SCM_BOOL_T);
 259     }
 260   set_empty (invisible_b ());
 261   set_spacing_hints ();
 262 }
 263
 264
 265
 266 /**
 267    set stem directions for hinting the optical spacing correction.
 268
 269    Modifies DIR_LIST property of the Stem's Score_column
 270
 271    TODO: more advanced: supply height of noteheads as well, for more advanced spacing possibilities
 272  */
 273 void
 274 Stem::set_spacing_hints ()
 275 {
 276   if (!invisible_b ())
 277     {
 278       SCM scmdir  = gh_int2scm (dir_);
 279       SCM dirlist = column_l ()->get_elt_property (dir_list_scm_sym);
 280       if (dirlist == SCM_BOOL_F)
 281         dirlist = SCM_EOL;
 282       else
 283         dirlist = SCM_CDR (dirlist);
 284
 285       if (scm_sloppy_memq (scmdir, dirlist) == SCM_EOL)
 286         {
 287           dirlist = gh_cons (scmdir, dirlist);
 288           column_l ()->set_elt_property (dir_list_scm_sym, dirlist);
 289         }
 290     }
 291 }
 292
 293 Molecule
 294 Stem::flag () const
 295 {
 296   String style;
 297   SCM st = get_elt_property (style_scm_sym);
 298   if ( st != SCM_BOOL_F)
 299     {
 300       st = SCM_CDR(st);
 301       style = ly_scm2string (st);
 302     }
 303
 304   char c = (dir_ == UP) ? 'u' : 'd';
 305   Molecule m = lookup_l ()->afm_find (String ("flags-") + to_str (c) +
 306                                       to_str (flag_i_));
 307   if (!style.empty_b ())
 308     m.add_molecule(lookup_l ()->afm_find (String ("flags-") + to_str (c) + style));
 309   return m;
 310 }
 311
 312 Interval
 313 Stem::do_width () const
 314 {
 315   Interval r (0, 0);
 316   if (beam_l_ || abs (flag_i_) <= 2)
 317     ;   // TODO!
 318   else
 319     {
 320       r = flag ().dim_.x ();
 321       r += note_delta_f ();
 322     }
 323   return r;
 324 }
 325
 326
 327
 328
 329 const Real ANGLE = 20* (2.0*M_PI/360.0); // ugh!
 330
 331 Molecule*
 332 Stem::do_brew_molecule_p () const
 333 {
 334   Molecule *mol_p =new Molecule;
 335   Drul_array<Real> stem_y = yextent_drul_;
 336   Real dy = staff_line_leading_f ()/2.0;
 337
 338   Real head_wid = 0;
 339   if (head_l_arr_.size ())
 340     head_wid = head_l_arr_[0]->extent (X_AXIS).length ();
 341   stem_y[Direction(-dir_)] += dir_ * head_wid * tan(ANGLE)/(2*dy);
 342
 343   if (!invisible_b ())
 344     {
 345       Real stem_width = paper_l ()->get_var ("stemthickness");
 346       Molecule ss =lookup_l ()->filledbox (Box (Interval (-stem_width/2, stem_width/2),
 347                                                  Interval (stem_y[DOWN]*dy, stem_y[UP]*dy)));
 348       mol_p->add_molecule (ss);
 349     }
 350
 351   if (!beam_l_ && abs (flag_i_) > 2)
 352     {
 353       Molecule fl = flag ();
 354       fl.translate_axis(stem_y[dir_]*dy, Y_AXIS);
 355       mol_p->add_molecule (fl);
 356     }
 357
 358   if (head_l_arr_.size())
 359     {
 360       mol_p->translate_axis (note_delta_f (), X_AXIS);
 361     }
 362   return mol_p;
 363 }
 364
 365 Real
 366 Stem::note_delta_f () const
 367 {
 368   Real r=0;
 369   if (head_l_arr_.size())
 370     {
 371       Interval head_wid(0,  head_l_arr_[0]->extent (X_AXIS).length ());
 372       Real rule_thick(paper_l ()->rule_thickness ());
 373       Interval stem_wid(-rule_thick/2, rule_thick/2);
 374       if (dir_ == CENTER)
 375         r = head_wid.center ();
 376       else
 377         r = head_wid[dir_] - stem_wid[dir_];
 378     }
 379   return r;
 380 }
 381
 382 Real
 383 Stem::hpos_f () const
 384 {
 385   return note_delta_f () + Item::hpos_f ();
 386 }
 387
 388 void
 389 Stem::do_substitute_element_pointer (Score_element*o,Score_element*n)
 390 {
 391   if (Note_head*h=dynamic_cast<Note_head*> (o))
 392     head_l_arr_.substitute (h, dynamic_cast<Note_head*>(n));
 393   if (Rest *r=dynamic_cast<Rest*> (o))
 394     rest_l_arr_.substitute (r, dynamic_cast<Rest*>(n));
 395   if (Beam* b = dynamic_cast<Beam*> (o))
 396     {
 397       if (b == beam_l_)
 398         beam_l_ = dynamic_cast<Beam*> (n);
 399     }
 400   Staff_symbol_referencer::do_substitute_element_pointer (o,n);
 401 }