2 beam-engraver.cc -- implement Beam_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1998--2004 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_point();
58 virtual bool valid_end_point ();
61 TRANSLATOR_DECLARATIONS( Beam_engraver );
66 Hmm. this isn't necessary, since grace beams and normal beams are
70 Beam_engraver::valid_start_point()
72 Moment n = now_mom ();
74 return n.grace_part_ == Rational (0);
78 Beam_engraver::valid_end_point()
80 return valid_start_point ();
83 Beam_engraver::Beam_engraver ()
87 finished_beam_info_=0;
90 evs_drul_[LEFT] = evs_drul_[RIGHT] =0;
95 Beam_engraver::try_music (Music *m)
97 if (m->is_mus_type ("beam-event"))
99 Direction d = to_dir (m->get_mus_property ("span-direction"));
100 if (d == START && !valid_start_point ())
102 if (d == STOP && !valid_end_point ())
119 Beam_engraver::set_melisma (bool ml)
121 SCM b = get_property ("autoBeaming");
123 daddy_trans_->set_property ("beamMelismaBusy", ml ? SCM_BOOL_T :SCM_BOOL_F);
127 Beam_engraver::process_music ()
132 finished_beam_ = beam_;
133 finished_beam_info_ = beam_info_;
139 if (beam_ && !to_boolean (get_property ("allowBeamBreak")))
141 top_engraver ()->forbid_breaks ();
144 if (evs_drul_[START])
148 evs_drul_[START]->origin ()->warning (_ ("already have a beam"));
153 prev_start_ev_ = evs_drul_[START];
154 beam_ = make_spanner ("Beam");
155 SCM smp = get_property ("measurePosition");
156 Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
158 beam_start_location_ = mp;
159 beam_start_mom_ = now_mom ();
161 beam_info_ = new Beaming_info_list;
163 /* urg, must copy to Auto_beam_engraver too */
164 announce_grob (beam_, evs_drul_[START]->self_scm());
171 Beam_engraver::typeset_beam ()
175 finished_beam_info_->beamify(beat_length_, subdivide_beams_);
176 Beam::set_beaming (finished_beam_, finished_beam_info_);
177 typeset_grob (finished_beam_);
178 delete finished_beam_info_;
179 finished_beam_info_ =0;
185 Beam_engraver::start_translation_timestep ()
187 evs_drul_ [START] =0;
194 subdivide_beams_ = to_boolean(get_property("subdivideBeams"));
195 beat_length_ = *unsmob_moment (get_property ("beatLength"));
200 Beam_engraver::stop_translation_timestep ()
205 finished_beam_ = beam_;
206 finished_beam_info_ = beam_info_;
217 Beam_engraver::finalize ()
222 prev_start_ev_->origin ()->warning (_ ("unterminated beam"));
225 we don't typeset it, (we used to, but it was commented
226 out. Reason unknown) */
233 Beam_engraver::acknowledge_grob (Grob_info info)
237 if (Rest::has_interface (info.grob_))
239 info.grob_->add_offset_callback (Beam::rest_collision_callback_proc, Y_AXIS);
241 else if (Stem::has_interface (info.grob_))
243 Moment now = now_mom();
245 if (!valid_start_point ())
248 Item *stem = dynamic_cast<Item*> (info.grob_);
249 if (Stem::get_beam (stem))
252 Music* m = info.music_cause();
253 if (!m->is_mus_type ("rhythmic-event"))
255 String s = _ ("stem must have Rhythmic structure");
256 if (info.music_cause ())
257 info.music_cause ()->origin ()->warning (s);
265 last_stem_added_at_ = now;
266 int durlog = unsmob_duration (m->get_mus_property ("duration"))-> duration_log ();
269 m->origin ()->warning (_ ("stem doesn't fit in beam"));
270 prev_start_ev_->origin ()->warning (_ ("beam was started here"));
274 [r4 c8] can just as well be modern notation.
278 stem->set_grob_property ("duration-log",
279 scm_int2num (durlog));
280 Moment stem_location = now - beam_start_mom_ + beam_start_location_;
281 beam_info_->add_stem (stem_location,
283 Beam::add_stem (beam_, stem);
292 ENTER_DESCRIPTION(Beam_engraver,
293 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will be "
294 "printed with flags instead of beams.",
296 /* accepts */ "beam-event",
297 /* acks */ "stem-interface rest-interface",
298 /* reads */ "beamMelismaBusy beatLength subdivideBeams",
302 class Grace_beam_engraver : public Beam_engraver
305 TRANSLATOR_DECLARATIONS(Grace_beam_engraver);
308 virtual bool valid_start_point();
309 virtual bool valid_end_point ();
312 Grace_beam_engraver::Grace_beam_engraver()
317 Grace_beam_engraver::valid_start_point()
319 Moment n = now_mom ();
321 return n.grace_part_ != Rational (0);
326 Grace_beam_engraver::valid_end_point ()
328 return beam_ && valid_start_point ();
333 ENTER_DESCRIPTION(Grace_beam_engraver,
334 /* descr */ "Handles Beam events by engraving Beams. If omitted, then notes will "
335 "be printed with flags instead of beams. Only engraves beams when we "
336 " are at grace points in time. "
339 /* accepts */ "beam-event",
340 /* acks */ "stem-interface rest-interface",
341 /* reads */ "beamMelismaBusy beatLength allowBeamBreak subdivideBeams",