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"));
109 if (d == START && !valid_start_moment ())
111 if (d == STOP && !valid_end_moment ())
128 Beam_engraver::set_melisma (bool ml)
130 SCM m = get_property ("automaticMelismata");
131 SCM b = get_property ("autoBeaming");
133 if (to_boolean (m) && !to_boolean (b))
134 daddy_trans_->set_property ("beamMelismaBusy", ml ? SCM_BOOL_T :SCM_BOOL_F);
138 Beam_engraver::process_music ()
143 finished_beam_ = beam_;
144 finished_beam_info_ = beam_info_;
150 if (beam_ && !to_boolean (get_property ("allowBeamBreak")))
152 top_engraver ()->forbid_breaks ();
155 if (evs_drul_[START])
159 evs_drul_[START]->origin ()->warning (_ ("already have a beam"));
164 prev_start_ev_ = evs_drul_[START];
165 beam_ = new Spanner (get_property ("Beam"));
166 SCM smp = get_property ("measurePosition");
167 Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
169 beam_start_location_ = mp;
170 beam_start_mom_ = now_mom ();
172 beam_info_ = new Beaming_info_list;
174 /* urg, must copy to Auto_beam_engraver too */
176 announce_grob(beam_, evs_drul_[START]->self_scm());
183 Beam_engraver::typeset_beam ()
187 finished_beam_info_->beamify(beat_length_, subdivide_beams_);
188 Beam::set_beaming (finished_beam_, finished_beam_info_);
189 typeset_grob (finished_beam_);
190 delete finished_beam_info_;
191 finished_beam_info_ =0;
197 Beam_engraver::start_translation_timestep ()
199 evs_drul_ [START] =0;
206 subdivide_beams_ = to_boolean(get_property("subdivideBeams"));
207 beat_length_ = *unsmob_moment (get_property ("beatLength"));
212 Beam_engraver::stop_translation_timestep ()
217 finished_beam_ = beam_;
218 finished_beam_info_ = beam_info_;
229 Beam_engraver::finalize ()
234 prev_start_ev_->origin ()->warning (_ ("unterminated beam"));
237 we don't typeset it, (we used to, but it was commented
238 out. Reason unknown) */
245 Beam_engraver::acknowledge_grob (Grob_info info)
249 if (Rest::has_interface (info.grob_))
251 info.grob_->add_offset_callback (Beam::rest_collision_callback_proc, Y_AXIS);
253 else if (Stem::has_interface (info.grob_))
255 Moment now = now_mom();
257 if (!valid_start_moment ())
260 Item *stem = dynamic_cast<Item*> (info.grob_);
261 if (Stem::get_beam (stem))
264 Music* m = info.music_cause();
265 if (!m->is_mus_type ("rhythmic-event"))
267 String s = _ ("stem must have Rhythmic structure");
268 if (info.music_cause ())
269 info.music_cause ()->origin ()->warning (s);
277 last_stem_added_at_ = now;
278 int durlog = unsmob_duration (m->get_mus_property ("duration"))-> duration_log ();
281 m->origin ()->warning (_ ("stem doesn't fit in beam"));
282 prev_start_ev_->origin ()->warning (_ ("beam was started here"));
286 [r4 c8] can just as well be modern notation.
290 stem->set_grob_property ("duration-log",
291 scm_int2num (durlog));
292 Moment stem_location = now - beam_start_mom_ + beam_start_location_;
293 beam_info_->add_stem (stem_location,
295 Beam::add_stem (beam_, stem);
304 ENTER_DESCRIPTION(Beam_engraver,
305 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will be "
306 "printed with flags instead of beams.",
308 /* accepts */ "beam-event abort-event",
309 /* acks */ "stem-interface rest-interface",
310 /* reads */ "beamMelismaBusy beatLength subdivideBeams",
314 class Grace_beam_engraver : public Beam_engraver
317 TRANSLATOR_DECLARATIONS(Grace_beam_engraver);
320 virtual bool valid_start_moment();
321 virtual bool valid_end_moment ();
324 Grace_beam_engraver::Grace_beam_engraver()
329 Grace_beam_engraver::valid_start_moment()
331 Moment n = now_mom ();
333 return n.grace_part_ != Rational (0);
338 Grace_beam_engraver::valid_end_moment ()
340 return beam_ && last_stem_added_at_.grace_part_ != Rational(0);
345 ENTER_DESCRIPTION(Grace_beam_engraver,
346 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will "
347 "be printed with flags instead of beams. Only engraves beams when we "
348 " are at grace points in time. "
351 /* accepts */ "beam-event abort-event",
352 /* acks */ "stem-interface rest-interface",
353 /* reads */ "beamMelismaBusy beatLength allowBeamBreak subdivideBeams",