lily/auto-beam-engraver.cc

   1 /*
   2   auto-beam-engraver.cc -- implement Auto_beam_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1999--2008 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "bar-line.hh"
  10 #include "beaming-pattern.hh"
  11 #include "beam.hh"
  12 #include "context.hh"
  13 #include "duration.hh"
  14 #include "engraver.hh"
  15 #include "item.hh"
  16 #include "rest.hh"
  17 #include "spanner.hh"
  18 #include "stream-event.hh"
  19 #include "stem.hh"
  20 #include "warn.hh"
  21
  22 #include "translator.icc"
  23
  24 class Auto_beam_engraver : public Engraver
  25 {
  26   TRANSLATOR_DECLARATIONS (Auto_beam_engraver);
  27
  28 protected:
  29   void stop_translation_timestep ();
  30   void process_music ();
  31   virtual void finalize ();
  32   virtual void derived_mark () const;
  33
  34   DECLARE_ACKNOWLEDGER (rest);
  35   DECLARE_ACKNOWLEDGER (beam);
  36   DECLARE_ACKNOWLEDGER (bar_line);
  37   DECLARE_ACKNOWLEDGER (stem);
  38   DECLARE_TRANSLATOR_LISTENER (beam_forbid);
  39
  40   void process_acknowledged ();
  41
  42 private:
  43   bool test_moment (Direction, Moment);
  44   void consider_begin (Moment);
  45   void consider_end (Moment);
  46   Spanner *create_beam ();
  47   void begin_beam ();
  48   void end_beam ();
  49   void junk_beam ();
  50   bool is_same_grace_state (Grob *e);
  51   void typeset_beam ();
  52
  53   Stream_event *forbid_;
  54   /*
  55     shortest_mom is the shortest note in the beam.
  56   */
  57   Moment shortest_mom_;
  58   Spanner *finished_beam_;
  59   vector<Item*> *stems_;
  60
  61   int process_acknowledged_count_;
  62   Moment last_add_mom_;
  63   /*
  64     Projected ending of the  beam we're working on.
  65   */
  66   Moment extend_mom_;
  67   Moment beam_start_moment_;
  68   Moment beam_start_location_;
  69
  70   // We act as if beam were created, and start a grouping anyway.
  71   Beaming_pattern *grouping_;
  72   SCM beam_settings_;
  73
  74   Beaming_pattern *finished_grouping_;
  75
  76
  77   Beaming_options beaming_options_;
  78   Beaming_options finished_beaming_options_;
  79
  80
  81   void check_bar_property ();
  82 };
  83
  84 void
  85 Auto_beam_engraver::derived_mark () const
  86 {
  87   scm_gc_mark (beam_settings_);
  88 }
  89
  90 void
  91 Auto_beam_engraver::check_bar_property ()
  92 {
  93   /* Duplicated from process_music (), since
  94      Repeat_acknowledge_engraver::process_music () may also set whichBar.  */
  95
  96   Moment now = now_mom ();
  97   if (scm_is_string (get_property ("whichBar"))
  98       && beam_start_moment_ < now)
  99     {
 100       consider_end (shortest_mom_);
 101       junk_beam ();
 102     }
 103 }
 104
 105 void
 106 Auto_beam_engraver::process_music ()
 107 {
 108   /*
 109     don't beam over skips
 110   */
 111   if (stems_)
 112     {
 113       Moment now = now_mom ();
 114       if (extend_mom_ < now)
 115         end_beam ();
 116     }
 117
 118   if (scm_is_string (get_property ("whichBar")))
 119     {
 120       consider_end (shortest_mom_);
 121       junk_beam ();
 122     }
 123
 124   if (forbid_)
 125     {
 126       consider_end (shortest_mom_);
 127       junk_beam ();
 128     }
 129 }
 130
 131 Auto_beam_engraver::Auto_beam_engraver ()
 132 {
 133   forbid_ = 0;
 134   process_acknowledged_count_ = 0;
 135   stems_ = 0;
 136   shortest_mom_ = Moment (Rational (1, 8));
 137   finished_beam_ = 0;
 138   finished_grouping_ = 0;
 139   grouping_ = 0;
 140   beam_settings_ = SCM_EOL;
 141 }
 142
 143 IMPLEMENT_TRANSLATOR_LISTENER (Auto_beam_engraver, beam_forbid);
 144 void
 145 Auto_beam_engraver::listen_beam_forbid (Stream_event *ev)
 146 {
 147   ASSIGN_EVENT_ONCE (forbid_, ev);
 148 }
 149
 150 bool
 151 Auto_beam_engraver::test_moment (Direction dir, Moment test)
 152 {
 153   return scm_call_3 (get_property ("autoBeamCheck"),
 154                      context ()->self_scm (),
 155                      scm_from_int (dir),
 156                      test.smobbed_copy ())
 157     != SCM_BOOL_F;
 158 }
 159
 160 void
 161 Auto_beam_engraver::consider_begin (Moment test_mom)
 162 {
 163   bool on = to_boolean (get_property ("autoBeaming"));
 164   if (!stems_ && on
 165       && !forbid_)
 166     {
 167       bool b = test_moment (START, test_mom);
 168       if (b)
 169         begin_beam ();
 170     }
 171 }
 172
 173 void
 174 Auto_beam_engraver::consider_end (Moment test_mom)
 175 {
 176   if (stems_)
 177     {
 178       /* Allow already started autobeam to end:
 179          don't check for autoBeaming */
 180       bool b = test_moment (STOP, test_mom);
 181       if (b)
 182         end_beam ();
 183     }
 184 }
 185
 186 Spanner *
 187 Auto_beam_engraver::create_beam ()
 188 {
 189   if (to_boolean (get_property ("skipTypesetting")))
 190     return 0;
 191
 192   for (vsize i = 0; i < stems_->size (); i++)
 193     if (Stem::get_beam ((*stems_)[i]))
 194       return 0;
 195
 196   /*
 197     Can't use make_spanner_from_properties () because we have to use
 198     beam_settings_.
 199   */
 200   Spanner *beam = new Spanner (beam_settings_);
 201
 202   for (vsize i = 0; i < stems_->size (); i++)
 203     Beam::add_stem (beam, (*stems_)[i]);
 204
 205   announce_grob (beam, (*stems_)[0]->self_scm ());
 206
 207   return beam;
 208 }
 209
 210 void
 211 Auto_beam_engraver::begin_beam ()
 212 {
 213   if (stems_ || grouping_)
 214     {
 215       programming_error ("already have autobeam");
 216       return;
 217     }
 218
 219   stems_ = new vector<Item*>;
 220   grouping_ = new Beaming_pattern ();
 221   beaming_options_.from_context (context ());
 222   beam_settings_ = updated_grob_properties (context (), ly_symbol2scm ("Beam"));
 223
 224   beam_start_moment_ = now_mom ();
 225   beam_start_location_
 226     = robust_scm2moment (get_property ("measurePosition"), Moment (0));
 227 }
 228
 229 void
 230 Auto_beam_engraver::junk_beam ()
 231 {
 232   if (!stems_)
 233     return;
 234
 235   delete stems_;
 236   stems_ = 0;
 237   delete grouping_;
 238   grouping_ = 0;
 239   beam_settings_ = SCM_EOL;
 240
 241   shortest_mom_ = Moment (Rational (1, 8));
 242 }
 243
 244 void
 245 Auto_beam_engraver::end_beam ()
 246 {
 247   if (stems_->size () < 2)
 248     junk_beam ();
 249   else
 250     {
 251       finished_beam_ = create_beam ();
 252
 253       if (finished_beam_)
 254         {
 255           announce_end_grob (finished_beam_, SCM_EOL);
 256           finished_grouping_ = grouping_;
 257           finished_beaming_options_ = beaming_options_;
 258         }
 259       delete stems_;
 260       stems_ = 0;
 261       grouping_ = 0;
 262       beam_settings_ = SCM_EOL;
 263     }
 264
 265   shortest_mom_ = Moment (Rational (1, 8));
 266 }
 267
 268 void
 269 Auto_beam_engraver::typeset_beam ()
 270 {
 271   if (finished_beam_)
 272     {
 273       if (!finished_beam_->get_bound (RIGHT))
 274         finished_beam_->set_bound (RIGHT, finished_beam_->get_bound (LEFT));
 275
 276       finished_grouping_->beamify (finished_beaming_options_);
 277       Beam::set_beaming (finished_beam_, finished_grouping_);
 278       finished_beam_ = 0;
 279
 280       delete finished_grouping_;
 281       finished_grouping_ = 0;
 282     }
 283 }
 284
 285 void
 286 Auto_beam_engraver::stop_translation_timestep ()
 287 {
 288   typeset_beam ();
 289   process_acknowledged_count_ = 0;
 290   forbid_ = 0;
 291 }
 292
 293 void
 294 Auto_beam_engraver::finalize ()
 295 {
 296   /* finished beams may be typeset */
 297   typeset_beam ();
 298   /* but unfinished may need another announce/acknowledge pass */
 299   if (stems_)
 300     junk_beam ();
 301 }
 302
 303
 304 void
 305 Auto_beam_engraver::acknowledge_beam (Grob_info info)
 306 {
 307   (void)info;
 308   check_bar_property ();
 309   if (stems_)
 310     end_beam ();
 311 }
 312
 313 void
 314 Auto_beam_engraver::acknowledge_bar_line (Grob_info info)
 315 {
 316   (void)info;
 317   check_bar_property ();
 318   if (stems_)
 319     end_beam ();
 320 }
 321
 322 void
 323 Auto_beam_engraver::acknowledge_rest (Grob_info info)
 324 {
 325   (void)info;
 326   check_bar_property ();
 327   if (stems_)
 328     end_beam ();
 329 }
 330
 331 void
 332 Auto_beam_engraver::acknowledge_stem (Grob_info info)
 333 {
 334   check_bar_property ();
 335   Item *stem = dynamic_cast<Item *> (info.grob ());
 336   Stream_event *ev = info.ultimate_event_cause ();
 337   if (!ev->in_event_class ("rhythmic-event"))
 338     {
 339       programming_error ("stem must have rhythmic structure");
 340       return;
 341     }
 342
 343   /*
 344     Don't (start) auto-beam over empty stems; skips or rests
 345   */
 346   if (!Stem::head_count (stem))
 347     {
 348       if (stems_)
 349         end_beam ();
 350       return;
 351     }
 352
 353   if (Stem::get_beam (stem))
 354     {
 355       if (stems_)
 356         junk_beam ();
 357       return;
 358     }
 359
 360   int durlog = unsmob_duration (ev->get_property ("duration"))->duration_log ();
 361
 362   if (durlog <= 2)
 363     {
 364       if (stems_)
 365         end_beam ();
 366       return;
 367     }
 368
 369   /*
 370     ignore grace notes.
 371   */
 372   Moment now = now_mom ();
 373   if (bool (beam_start_location_.grace_part_) != bool (now.grace_part_))
 374     return;
 375
 376   Moment dur = unsmob_duration (ev->get_property ("duration"))->get_length ();
 377
 378   consider_end (dur);
 379   consider_begin (dur);
 380
 381   if (dur < shortest_mom_)
 382     shortest_mom_ = dur;
 383
 384   if (!stems_)
 385     return;
 386
 387   grouping_->add_stem (now - beam_start_moment_ + beam_start_location_,
 388                        durlog - 2,
 389                        Stem::is_invisible (stem));
 390   stems_->push_back (stem);
 391   last_add_mom_ = now;
 392   extend_mom_ = max (extend_mom_, now) + get_event_length (ev, now);
 393 }
 394
 395 void
 396 Auto_beam_engraver::process_acknowledged ()
 397 {
 398   if (extend_mom_ > now_mom ())
 399     return;
 400
 401   if (!process_acknowledged_count_)
 402     {
 403       consider_end (shortest_mom_);
 404       consider_begin (shortest_mom_);
 405     }
 406   else if (process_acknowledged_count_ > 1)
 407     {
 408       if (stems_)
 409         {
 410           Moment now = now_mom ();
 411           if ((extend_mom_ < now)
 412               || ((extend_mom_ == now) && (last_add_mom_ != now)))
 413             end_beam ();
 414           else if (!stems_->size ())
 415             junk_beam ();
 416         }
 417     }
 418
 419   process_acknowledged_count_++;
 420 }
 421
 422 ADD_ACKNOWLEDGER (Auto_beam_engraver, stem);
 423 ADD_ACKNOWLEDGER (Auto_beam_engraver, bar_line);
 424 ADD_ACKNOWLEDGER (Auto_beam_engraver, beam);
 425 ADD_ACKNOWLEDGER (Auto_beam_engraver, rest);
 426 ADD_TRANSLATOR (Auto_beam_engraver,
 427                 /* doc */
 428                 "Generate beams based on measure characteristics and observed"
 429                 " Stems.  Uses @code{beatLength}, @code{measureLength}, and"
 430                 " @code{measurePosition} to decide when to start and stop a"
 431                 " beam.  Overriding beaming is done through"
 432                 " @ref{Stem_engraver} properties @code{stemLeftBeamCount} and"
 433                 " @code{stemRightBeamCount}.",
 434
 435                 /* create */
 436                 "Beam ",
 437
 438                 /* read */
 439                 "autoBeaming "
 440                 "autoBeamSettings "
 441                 "beatLength "
 442                 "subdivideBeams ",
 443
 444                 /* write */
 445                 ""
 446                 );