2 auto-beam-engraver.cc -- implement Auto_beam_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1999--2005 Jan Nieuwenhuizen <janneke@gnu.org>
14 #include "bar-line.hh"
19 #include "duration.hh"
22 class Auto_beam_engraver : public Engraver
24 TRANSLATOR_DECLARATIONS (Auto_beam_engraver);
27 virtual void stop_translation_timestep ();
28 virtual void start_translation_timestep ();
29 virtual void process_music ();
30 virtual bool try_music (Music *);
31 virtual void finalize ();
32 virtual void acknowledge_grob (Grob_info);
33 virtual void process_acknowledged_grobs ();
36 bool test_moment (Direction, Moment);
37 void consider_begin (Moment);
38 void consider_end (Moment);
39 Spanner *create_beam ();
43 bool is_same_grace_state (Grob *e);
48 shortest_mom is the shortest note in the beam.
51 Spanner *finished_beam_;
52 Link_array<Item> *stems_;
54 int process_acknowledged_count_;
57 Projected ending of the beam we're working on.
60 Moment beam_start_moment_;
61 Moment beam_start_location_;
63 bool subdivide_beams_;
66 // We act as if beam were created, and start a grouping anyway.
67 Beaming_info_list *grouping_;
68 SCM beam_settings_; // ugh. should protect ?
70 Beaming_info_list *finished_grouping_;
74 Auto_beam_engraver::process_music ()
76 if (scm_is_string (get_property ("whichBar")))
78 consider_end (shortest_mom_);
84 consider_end (shortest_mom_);
89 Auto_beam_engraver::Auto_beam_engraver ()
92 process_acknowledged_count_ = 0;
94 shortest_mom_ = Moment (Rational (1, 8));
96 finished_grouping_ = 0;
98 beam_settings_ = SCM_EOL;
102 Auto_beam_engraver::try_music (Music *m)
104 if (m->is_mus_type ("beam-forbid-event"))
114 Auto_beam_engraver::test_moment (Direction dir, Moment test)
116 return scm_call_3 (get_property ("autoBeamCheck"),
117 context ()->self_scm (),
119 test.smobbed_copy ())
124 Auto_beam_engraver::consider_begin (Moment test_mom)
126 bool on = to_boolean (get_property ("autoBeaming"));
130 bool b = test_moment (START, test_mom);
137 Auto_beam_engraver::consider_end (Moment test_mom)
141 /* Allow already started autobeam to end:
142 don't check for autoBeaming */
143 bool b = test_moment (STOP, test_mom);
150 Auto_beam_engraver::create_beam ()
152 if (to_boolean (get_property ("skipTypesetting")))
155 Spanner *beam = new Spanner (beam_settings_, context ()->get_grob_key ("Beam"));
156 for (int i = 0; i < stems_->size (); i++)
159 watch out for stem tremolos and abbreviation beams
161 if (Stem::get_beam ((*stems_)[i]))
163 scm_gc_unprotect_object (beam->self_scm ());
166 Beam::add_stem (beam, (*stems_)[i]);
169 announce_grob (beam, (*stems_)[0]->self_scm ());
175 Auto_beam_engraver::begin_beam ()
177 if (stems_ || grouping_)
179 programming_error ("already have autobeam");
183 stems_ = new Link_array<Item>;
184 grouping_ = new Beaming_info_list;
185 beam_settings_ = updated_grob_properties (context (), ly_symbol2scm ("Beam"));
187 beam_start_moment_ = now_mom ();
189 = robust_scm2moment (get_property ("measurePosition"), Moment (0));
190 subdivide_beams_ = ly_scm2bool (get_property ("subdivideBeams"));
191 beat_length_ = robust_scm2moment (get_property ("beatLength"), Moment (1, 4));
195 Auto_beam_engraver::junk_beam ()
204 beam_settings_ = SCM_EOL;
206 shortest_mom_ = Moment (Rational (1, 8));
210 Auto_beam_engraver::end_beam ()
212 if (stems_->size () < 2)
218 finished_beam_ = create_beam ();
220 finished_grouping_ = grouping_;
224 beam_settings_ = SCM_EOL;
227 shortest_mom_ = Moment (Rational (1, 8));
231 Auto_beam_engraver::typeset_beam ()
235 finished_grouping_->beamify (beat_length_, subdivide_beams_);
236 Beam::set_beaming (finished_beam_, finished_grouping_);
239 delete finished_grouping_;
240 finished_grouping_ = 0;
245 Auto_beam_engraver::start_translation_timestep ()
247 process_acknowledged_count_ = 0;
249 don't beam over skips
253 Moment now = now_mom ();
254 if (extend_mom_ < now)
263 Auto_beam_engraver::stop_translation_timestep ()
269 Auto_beam_engraver::finalize ()
271 /* finished beams may be typeset */
273 /* but unfinished may need another announce/acknowledge pass */
279 Auto_beam_engraver::acknowledge_grob (Grob_info info)
281 /* Duplicated from process_music (), since
282 Repeat_acknowledge_engraver::process_music () may also set whichBar. */
284 Moment now = now_mom ();
285 if (scm_is_string (get_property ("whichBar"))
286 && beam_start_moment_ < now)
288 consider_end (shortest_mom_);
294 if (Beam::has_interface (info.grob ()))
298 else if (Bar_line::has_interface (info.grob ()))
302 else if (Rest::has_interface (info.grob ()))
308 if (Stem::has_interface (info.grob ()))
310 Item *stem = dynamic_cast<Item *> (info.grob ());
311 Music *m = info.music_cause ();
312 if (!m->is_mus_type ("rhythmic-event"))
314 programming_error ("stem must have rhythmic structure");
319 Don't (start) auto-beam over empty stems; skips or rests
321 if (!Stem::head_count (stem))
328 if (Stem::get_beam (stem))
335 int durlog = unsmob_duration (m->get_property ("duration"))->duration_log ();
347 if (bool (beam_start_location_.grace_part_) != bool (now.grace_part_))
350 Moment dur = unsmob_duration (m->get_property ("duration"))->get_length ();
353 consider_begin (dur);
355 if (dur < shortest_mom_)
361 grouping_->add_stem (now - beam_start_moment_ + beam_start_location_,
365 extend_mom_ = max (extend_mom_, now) + m->get_length ();
370 Auto_beam_engraver::process_acknowledged_grobs ()
372 if (extend_mom_ > now_mom ())
375 if (!process_acknowledged_count_)
377 consider_end (shortest_mom_);
378 consider_begin (shortest_mom_);
380 else if (process_acknowledged_count_ > 1)
384 Moment now = now_mom ();
385 if ((extend_mom_ < now)
386 || ((extend_mom_ == now) && (last_add_mom_ != now)))
390 else if (!stems_->size ())
397 process_acknowledged_count_++;
400 ADD_TRANSLATOR (Auto_beam_engraver,
401 /* descr */ "Generate beams based on measure characteristics and observed "
402 "Stems. Uses beatLength, measureLength and measurePosition to decide "
403 "when to start and stop a beam. Overriding beaming is done through "
404 "@ref{Stem_engraver} properties @code{stemLeftBeamCount} and "
405 "@code{stemRightBeamCount}. ",
407 /* accepts */ "beam-forbid-event",
408 /* acks */ "stem-interface rest-interface beam-interface bar-line-interface",
409 /* reads */ "autoBeaming autoBeamSettings beatLength subdivideBeams",