2 beam-engraver.cc -- implement Beam_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1998--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
9 #include "engraver-group-engraver.hh"
10 #include "engraver.hh"
16 #include "score-engraver.hh"
18 #include "drul-array.hh"
22 class Beam_engraver : public Engraver
25 Drul_array<Music*> evs_drul_;
27 Spanner *finished_beam_;
29 Music * prev_start_ev_;
33 Beaming_info_list * beam_info_;
34 Beaming_info_list * finished_beam_info_;
36 /// location within measure where beam started.
37 Moment beam_start_location_;
39 /// moment (global time) where beam started.
40 Moment beam_start_mom_;
42 bool subdivide_beams_;
46 void set_melisma (bool);
48 Moment last_stem_added_at_;
49 virtual void stop_translation_timestep ();
50 virtual void start_translation_timestep ();
51 virtual void finalize ();
53 virtual void acknowledge_grob (Grob_info);
54 virtual bool try_music (Music*);
55 virtual void process_music ();
57 virtual bool valid_start_moment();
58 virtual bool valid_end_moment ();
61 TRANSLATOR_DECLARATIONS( Beam_engraver );
66 Hmm. this isn't necessary, since grace beams and normal beams are
70 Beam_engraver::valid_start_moment()
72 Moment n = now_mom ();
74 return n.grace_part_ == Rational (0);
78 Beam_engraver::valid_end_moment()
80 return last_stem_added_at_.grace_part_ == Rational(0);
84 Beam_engraver::Beam_engraver ()
88 finished_beam_info_=0;
91 evs_drul_[LEFT] = evs_drul_[RIGHT] =0;
96 Beam_engraver::try_music (Music *m)
98 if (m->is_mus_type ("abort-event"))
100 evs_drul_[START] = 0;
106 else if (m->is_mus_type ("beam-event"))
108 Direction d = to_dir (m->get_mus_property ("span-direction"));
110 if (d == STOP && !valid_end_moment())
113 if (d == START && !valid_start_moment ())
118 SCM m = get_property ("automaticMelismata");
119 SCM b = get_property ("autoBeaming");
120 if (to_boolean (m) && !to_boolean (b))
129 else if (m->is_mus_type ("new-beam-event"))
131 Direction d = to_dir (m->get_mus_property ("span-direction"));
132 if (d == START && !valid_start_moment ())
134 if (d == STOP && !valid_end_moment ())
149 Beam_engraver::set_melisma (bool m)
151 daddy_trans_->set_property ("beamMelismaBusy", m ? SCM_BOOL_T :SCM_BOOL_F);
155 Beam_engraver::process_music ()
160 finished_beam_ = beam_;
161 finished_beam_info_ = beam_info_;
167 if (beam_ && !to_boolean (get_property ("allowBeamBreak")))
169 top_engraver ()->forbid_breaks ();
172 if (evs_drul_[START])
176 evs_drul_[START]->origin ()->warning (_ ("already have a beam"));
180 prev_start_ev_ = evs_drul_[START];
181 beam_ = new Spanner (get_property ("Beam"));
182 SCM smp = get_property ("measurePosition");
183 Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
185 beam_start_location_ = mp;
186 beam_start_mom_ = now_mom ();
188 beam_info_ = new Beaming_info_list;
190 /* urg, must copy to Auto_beam_engraver too */
192 announce_grob(beam_, evs_drul_[START]->self_scm());
199 Beam_engraver::typeset_beam ()
203 finished_beam_info_->beamify(beat_length_, subdivide_beams_);
204 Beam::set_beaming (finished_beam_, finished_beam_info_);
205 typeset_grob (finished_beam_);
206 delete finished_beam_info_;
207 finished_beam_info_ =0;
213 Beam_engraver::start_translation_timestep ()
215 evs_drul_ [START] =0;
220 SCM m = get_property ("automaticMelismata");
221 SCM b = get_property ("autoBeaming");
222 if (to_boolean (m) && !to_boolean (b))
226 subdivide_beams_ = to_boolean(get_property("subdivideBeams"));
227 beat_length_ = *unsmob_moment (get_property ("beatLength"));
232 Beam_engraver::stop_translation_timestep ()
237 finished_beam_ = beam_;
238 finished_beam_info_ = beam_info_;
245 if (to_boolean (get_property ("automaticMelismata"))
246 && !to_boolean (get_property ("autoBeaming")))
254 Beam_engraver::finalize ()
259 prev_start_ev_->origin ()->warning (_ ("unterminated beam"));
262 we don't typeset it, (we used to, but it was commented
263 out. Reason unknown) */
270 Beam_engraver::acknowledge_grob (Grob_info info)
274 if (Rest::has_interface (info.grob_))
276 info.grob_->add_offset_callback (Beam::rest_collision_callback_proc, Y_AXIS);
278 else if (Stem::has_interface (info.grob_))
280 Moment now = now_mom();
282 if (!valid_start_moment ())
285 Item *stem = dynamic_cast<Item*> (info.grob_);
286 if (Stem::get_beam (stem))
289 Music* m = info.music_cause();
290 if (!m->is_mus_type ("rhythmic-event"))
292 String s = _ ("stem must have Rhythmic structure");
293 if (info.music_cause ())
294 info.music_cause ()->origin ()->warning (s);
302 last_stem_added_at_ = now;
303 int durlog = unsmob_duration (m->get_mus_property ("duration"))-> duration_log ();
306 m->origin ()->warning (_ ("stem doesn't fit in beam"));
307 prev_start_ev_->origin ()->warning (_ ("beam was started here"));
311 [r4 c8] can just as well be modern notation.
315 stem->set_grob_property ("duration-log",
316 scm_int2num (durlog));
317 Moment stem_location = now - beam_start_mom_ + beam_start_location_;
318 beam_info_->add_stem (stem_location,
320 Beam::add_stem (beam_, stem);
329 ENTER_DESCRIPTION(Beam_engraver,
330 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will be "
331 "printed with flags instead of beams.",
333 /* accepts */ "beam-event new-beam-event abort-event",
334 /* acks */ "stem-interface rest-interface",
335 /* reads */ "beamMelismaBusy beatLength subdivideBeams",
339 class Grace_beam_engraver : public Beam_engraver
342 TRANSLATOR_DECLARATIONS(Grace_beam_engraver);
345 virtual bool valid_start_moment();
346 virtual bool valid_end_moment ();
349 Grace_beam_engraver::Grace_beam_engraver()
354 Grace_beam_engraver::valid_start_moment()
356 Moment n = now_mom ();
358 return n.grace_part_ != Rational (0);
363 Grace_beam_engraver::valid_end_moment ()
365 return beam_ && last_stem_added_at_.grace_part_ != Rational(0);
370 ENTER_DESCRIPTION(Grace_beam_engraver,
371 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will "
372 "be printed with flags instead of beams. Only engraves beams when we "
373 " are at grace points in time. "
376 /* accepts */ "beam-event abort-event new-beam-event",
377 /* acks */ "stem-interface rest-interface",
378 /* reads */ "beamMelismaBusy beatLength allowBeamBreak subdivideBeams",