2 beam-engraver.cc -- implement Beam_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1998--2002 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*> reqs_drul_;
27 Spanner *finished_beam_;
29 Music * prev_start_req_;
31 Beaming_info_list * beam_info_;
32 Beaming_info_list * finished_beam_info_;
34 /// location within measure where beam started.
35 Moment beam_start_location_;
37 /// moment (global time) where beam started.
38 Moment beam_start_mom_;
40 bool subdivide_beams_;
44 void set_melisma (bool);
46 Moment last_stem_added_at_;
50 virtual void stop_translation_timestep ();
51 virtual void start_translation_timestep ();
52 virtual void finalize ();
54 virtual void acknowledge_grob (Grob_info);
55 virtual bool try_music (Music*);
56 virtual void process_music ();
58 virtual bool valid_start_moment();
59 virtual bool valid_end_moment ();
62 TRANSLATOR_DECLARATIONS( Beam_engraver );
67 Hmm. this isn't necessary, since grace beams and normal beams are
71 Beam_engraver::valid_start_moment()
73 Moment n = now_mom ();
75 return n.grace_part_ == Rational (0);
79 Beam_engraver::valid_end_moment()
81 return last_stem_added_at_.grace_part_ == Rational(0);
85 Beam_engraver::Beam_engraver ()
89 finished_beam_info_=0;
91 reqs_drul_[LEFT] = reqs_drul_[RIGHT] =0;
97 Beam_engraver::try_music (Music *m)
99 if (m->is_mus_type ("abort-event"))
101 reqs_drul_[START] = 0;
102 reqs_drul_[STOP] = 0;
107 else if (m->is_mus_type ("beam-event"))
109 Direction d = to_dir (m->get_mus_property ("span-direction"));
111 if (d == STOP && !valid_end_moment())
114 if (d == START && !valid_start_moment ())
119 SCM m = get_property ("automaticMelismata");
120 SCM b = get_property ("autoBeaming");
121 if (to_boolean (m) && !to_boolean (b))
134 Beam_engraver::set_melisma (bool m)
136 daddy_trans_->set_property ("beamMelismaBusy", m ? SCM_BOOL_T :SCM_BOOL_F);
140 Beam_engraver::process_music ()
142 if (reqs_drul_[STOP])
145 finished_beam_ = beam_;
146 finished_beam_info_ = beam_info_;
155 top_engraver ()->forbid_breaks ();
157 if (reqs_drul_[START])
161 reqs_drul_[START]->origin ()->warning (_ ("already have a beam"));
165 prev_start_req_ = reqs_drul_[START];
166 beam_ = new Spanner (get_property ("Beam"));
167 SCM smp = get_property ("measurePosition");
168 Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
170 beam_start_location_ = mp;
171 beam_start_mom_ = now_mom ();
173 beam_info_ = new Beaming_info_list;
175 /* urg, must copy to Auto_beam_engraver too */
177 announce_grob(beam_, reqs_drul_[START]->self_scm());
184 Beam_engraver::typeset_beam ()
188 finished_beam_info_->beamify(beat_length_, subdivide_beams_);
189 Beam::set_beaming (finished_beam_, finished_beam_info_);
190 typeset_grob (finished_beam_);
191 delete finished_beam_info_;
192 finished_beam_info_ =0;
198 Beam_engraver::start_translation_timestep ()
200 reqs_drul_ [START] =0;
201 reqs_drul_[STOP] = 0;
205 SCM m = get_property ("automaticMelismata");
206 SCM b = get_property ("autoBeaming");
207 if (to_boolean (m) && !to_boolean (b))
211 subdivide_beams_ = to_boolean(get_property("subdivideBeams"));
212 beat_length_ = *unsmob_moment (get_property ("beatLength"));
217 Beam_engraver::stop_translation_timestep ()
223 Beam_engraver::finalize ()
228 prev_start_req_->origin ()->warning (_ ("unterminated beam"));
231 we don't typeset it, (we used to, but it was commented
232 out. Reason unknown) */
239 Beam_engraver::acknowledge_grob (Grob_info info)
243 if (Rest::has_interface (info.grob_))
245 info.grob_->add_offset_callback (Beam::rest_collision_callback_proc, Y_AXIS);
247 else if (Stem::has_interface (info.grob_))
249 Moment now = now_mom();
251 if (!valid_start_moment ())
254 Item *stem = dynamic_cast<Item*> (info.grob_);
255 if (Stem::get_beam (stem))
258 Music* m = info.music_cause();
259 if (!m->is_mus_type ("rhythmic-event"))
261 String s = _ ("stem must have Rhythmic structure");
262 if (info.music_cause ())
263 info.music_cause ()->origin ()->warning (s);
271 last_stem_added_at_ = now;
272 int durlog = unsmob_duration (m->get_mus_property ("duration"))-> duration_log ();
275 m->origin ()->warning (_ ("stem doesn't fit in beam"));
276 prev_start_req_->origin ()->warning (_ ("beam was started here"));
280 [r4 c8] can just as well be modern notation.
284 stem->set_grob_property ("duration-log",
285 scm_int2num (durlog));
286 Moment stem_location = now - beam_start_mom_ + beam_start_location_;
287 beam_info_->add_stem (stem_location,
289 Beam::add_stem (beam_, stem);
298 ENTER_DESCRIPTION(Beam_engraver,
299 /* descr */ "Handles Beam_requests by engraving Beams. If omitted, then notes will be
300 printed with flags instead of beams.",
302 /* accepts */ "beam-event abort-event",
303 /* acks */ "stem-interface rest-interface",
304 /* reads */ "beamMelismaBusy beatLength subdivideBeams",
308 class Grace_beam_engraver : public Beam_engraver
311 TRANSLATOR_DECLARATIONS(Grace_beam_engraver);
314 virtual bool valid_start_moment();
315 virtual bool valid_end_moment ();
318 Grace_beam_engraver::Grace_beam_engraver()
323 Grace_beam_engraver::valid_start_moment()
325 Moment n = now_mom ();
327 return n.grace_part_ != Rational (0);
332 Grace_beam_engraver::valid_end_moment ()
334 return beam_ && last_stem_added_at_.grace_part_ != Rational(0);
339 ENTER_DESCRIPTION(Grace_beam_engraver,
340 /* descr */ "Handles Beam_requests by engraving Beams. If omitted, then notes will
341 be printed with flags instead of beams. Only engraves beams when we
342 are at grace points in time.
345 /* accepts */ "beam-event abort-event",
346 /* acks */ "stem-interface rest-interface",
347 /* reads */ "beamMelismaBusy beatLength subdivideBeams",