2 auto-beam-engraver.cc -- implement Auto_beam_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1999--2004 Jan Nieuwenhuizen <janneke@gnu.org>
15 #include "engraver-group-engraver.hh"
16 #include "bar-line.hh"
18 #include "engraver.hh"
21 #include "duration.hh"
27 class Auto_beam_engraver
: public Engraver
29 TRANSLATOR_DECLARATIONS (Auto_beam_engraver
);
31 virtual void stop_translation_timestep ();
32 virtual void start_translation_timestep ();
33 virtual void process_music ();
34 virtual bool try_music (Music
*);
35 virtual void finalize ();
36 virtual void acknowledge_grob (Grob_info
);
37 virtual void process_acknowledged_grobs ();
40 bool test_moment (Direction
, Moment
);
41 void consider_begin (Moment
);
42 void consider_end (Moment
);
43 Spanner
* create_beam ();
47 bool is_same_grace_state (Grob
* e
);
52 shortest_mom is the shortest note in the beam.
55 Spanner
*finished_beam_
;
56 Link_array
<Item
>* stems_
;
62 Projected ending of the beam we're working on.
65 Moment beam_start_moment_
;
66 Moment beam_start_location_
;
68 bool subdivide_beams_
;
71 // We act as if beam were created, and start a grouping anyway.
72 Beaming_info_list
*grouping_
;
73 SCM beam_settings_
; // ugh. should protect ?
75 Beaming_info_list
*finished_grouping_
;
79 Auto_beam_engraver::process_music ()
81 if (gh_string_p (get_property ("whichBar")))
83 consider_end (shortest_mom_
);
89 consider_end (shortest_mom_
);
95 Auto_beam_engraver::Auto_beam_engraver ()
100 shortest_mom_
= Moment (Rational (1, 8));
102 finished_grouping_
= 0;
104 beam_settings_
= SCM_EOL
;
109 Auto_beam_engraver::try_music (Music
*m
)
111 if (m
->is_mus_type ("beam-forbid-event"))
121 Determine end moment for auto beaming (or begin moment, but mostly
122 0==anywhere) In order of increasing priority:
124 i. begin anywhere, end at every beat
125 ii. end * <num> <den>
126 iii. end <type> <num> <den>
134 [to be defined in config file]
135 i. easy catch-all rule
136 ii. exceptions for time signature
137 iii. exceptions for time signature, for specific duration type
141 v. override for specific duration type
145 Auto_beam_engraver::test_moment (Direction dir
, Moment test_mom
)
147 Moment now
= now_mom ();
154 SCM wild
= scm_list_n (ly_symbol2scm ("*"), ly_symbol2scm ("*"), SCM_UNDEFINED
);
157 function
= scm_list_n (ly_symbol2scm ("begin"), SCM_UNDEFINED
);
159 function
= scm_list_n (ly_symbol2scm ("end"), SCM_UNDEFINED
);
161 Moment one_beat
= *unsmob_moment (get_property ("beatLength"));
162 int num
= int ((*unsmob_moment (get_property ("measureLength")) / one_beat
).main_part_
);
163 int den
= one_beat
.den ();
164 SCM time
= scm_list_n (scm_int2num (num
), scm_int2num (den
), SCM_UNDEFINED
);
166 SCM type
= scm_list_n (scm_int2num (test_mom
.num ()),
167 scm_int2num (test_mom
.den ()), SCM_UNDEFINED
);
171 settings aren't grob-properties.
173 SCM settings
= get_property ("autoBeamSettings");
177 /* begin beam at any position
178 (and fallback for end) */
181 /* end beam at end of beat */
184 SCM
beat (get_property ("beatLength"));
186 if (unsmob_moment (beat
))
187 moment
= *unsmob_moment (beat
);
190 /* second guess: property generic time exception */
191 SCM m
= scm_assoc (gh_append3 (function
, wild
, time
), settings
);
193 if (m
!= SCM_BOOL_F
&& unsmob_moment (ly_cdr (m
)))
194 moment
= * unsmob_moment (ly_cdr (m
));
196 /* third guess: property time exception, specific for duration type */
197 m
= scm_assoc (gh_append3 (function
, type
, time
), settings
);
198 if (m
!= SCM_BOOL_F
&& unsmob_moment (ly_cdr (m
)))
199 moment
= * unsmob_moment (ly_cdr (m
));
201 /* fourth guess [user override]: property plain generic */
202 m
= scm_assoc (gh_append3 (function
, wild
, wild
), settings
);
203 if (m
!= SCM_BOOL_F
&& unsmob_moment (ly_cdr (m
)))
204 moment
= * unsmob_moment (ly_cdr (m
));
206 /* fifth guess [user override]: property plain, specific for duration type */
207 m
= scm_assoc (gh_append3 (function
, type
, wild
), settings
);
208 if (m
!= SCM_BOOL_F
&& unsmob_moment (ly_cdr (m
)))
209 moment
= * unsmob_moment (ly_cdr (m
));
212 if (moment
.to_bool ())
214 /* Ugh? measurePosition can be negative, when \partial
215 We may have to fix this elsewhere (timing translator)
216 r = unsmob_moment (get_property ("measurePosition"))->mod_rat (moment);
218 Moment pos
= * unsmob_moment (get_property ("measurePosition"));
219 if (pos
< Moment (0))
221 Moment length
= * unsmob_moment (get_property ("measureLength"));
224 r
= pos
.main_part_
.mod_rat (moment
.main_part_
);
229 /* if undefined, starting is ok */
232 /* but ending is not */
240 Auto_beam_engraver::consider_begin (Moment test_mom
)
242 bool on
= to_boolean (get_property ("autoBeaming"));
246 bool b
= test_moment (START
, test_mom
);
253 Auto_beam_engraver::consider_end (Moment test_mom
)
257 /* Allow already started autobeam to end:
258 don't check for autoBeaming */
259 bool b
= test_moment (STOP
, test_mom
);
266 Auto_beam_engraver::create_beam ()
268 if (to_boolean (get_property ("skipTypesetting")))
273 Spanner
* beam
= new Spanner (beam_settings_
);
274 for (int i
= 0; i
< stems_
->size (); i
++)
277 watch out for stem tremolos and abbreviation beams
279 if (Stem::get_beam ((*stems_
)[i
]))
281 scm_gc_unprotect_object (beam
->self_scm ());
284 Beam::add_stem (beam
, (*stems_
)[i
]);
287 announce_grob (beam
, (*stems_
)[0]->self_scm ());
293 Auto_beam_engraver::begin_beam ()
295 if (stems_
|| grouping_
)
297 programming_error ("already have autobeam");
301 stems_
= new Link_array
<Item
>;
302 grouping_
= new Beaming_info_list
;
303 beam_settings_
= updated_grob_properties (daddy_context_
, ly_symbol2scm ("Beam"));
305 beam_start_moment_
= now_mom ();
306 beam_start_location_
= *unsmob_moment (get_property ("measurePosition"));
307 subdivide_beams_
= gh_scm2bool (get_property ("subdivideBeams"));
308 beat_length_
= *unsmob_moment (get_property ("beatLength"));
312 Auto_beam_engraver::junk_beam ()
321 beam_settings_
= SCM_EOL
;
323 shortest_mom_
= Moment (Rational (1, 8));
327 Auto_beam_engraver::end_beam ()
329 if (stems_
->size () < 2)
335 finished_beam_
= create_beam ();
337 finished_grouping_
= grouping_
;
341 beam_settings_
= SCM_EOL
;
344 shortest_mom_
= Moment (Rational (1, 8));
348 Auto_beam_engraver::typeset_beam ()
352 finished_grouping_
->beamify (beat_length_
, subdivide_beams_
);
353 Beam::set_beaming (finished_beam_
, finished_grouping_
);
354 typeset_grob (finished_beam_
);
357 delete finished_grouping_
;
358 finished_grouping_
= 0;
363 Auto_beam_engraver::start_translation_timestep ()
367 don't beam over skips
371 Moment now
= now_mom ();
372 if (extend_mom_
< now
)
381 Auto_beam_engraver::stop_translation_timestep ()
387 Auto_beam_engraver::finalize ()
389 /* finished beams may be typeset */
391 /* but unfinished may need another announce/acknowledge pass */
398 Auto_beam_engraver::acknowledge_grob (Grob_info info
)
402 if (Beam::has_interface (info
.grob_
))
406 else if (Bar_line::has_interface (info
.grob_
))
410 else if (Rest::has_interface (info
.grob_
))
416 if (Stem::has_interface (info
.grob_
))
418 Item
* stem
= dynamic_cast<Item
*> (info
.grob_
);
419 Music
* m
= info
.music_cause ();
420 if (!m
->is_mus_type ("rhythmic-event"))
422 programming_error ("Stem must have rhythmic structure");
427 Don't (start) auto-beam over empty stems; skips or rests
429 if (!Stem::head_count (stem
))
436 if (Stem::get_beam (stem
))
443 int durlog
= unsmob_duration (m
->get_property ("duration"))->duration_log ();
456 if (bool (beam_start_location_
.grace_part_
) != bool (now_mom ().grace_part_
))
460 Moment dur
= unsmob_duration (m
->get_property ("duration"))->get_length ();
463 This comment has been here since long:
465 if shortest duration would change
466 consider ending and beginning beam first.
468 but the code didn't match: */
471 consider_begin (dur
);
473 if (dur
< shortest_mom_
)
476 /* I very much suspect that we wanted: */
478 consider_end (shortest_mom_
);
479 if (dur
< shortest_mom_
)
482 consider_end (shortest_mom_
);
484 consider_begin (shortest_mom_
);
490 Moment now
= now_mom ();
492 grouping_
->add_stem (now
- beam_start_moment_
+ beam_start_location_
,
496 extend_mom_
= (extend_mom_
>? now
) + m
->get_length ();
501 Auto_beam_engraver::process_acknowledged_grobs ()
505 consider_end (shortest_mom_
);
506 consider_begin (shortest_mom_
);
512 Moment now
= now_mom ();
513 if ((extend_mom_
< now
)
514 || ((extend_mom_
== now
) && (last_add_mom_
!= now
)))
518 else if (!stems_
->size ())
528 ENTER_DESCRIPTION (Auto_beam_engraver
,
529 /* descr */ "Generate beams based on measure characteristics and observed "
530 "Stems. Uses beatLength, measureLength and measurePosition to decide "
531 "when to start and stop a beam. Overriding beaming is done through "
532 "@ref{Stem_engraver} properties @code{stemLeftBeamCount} and "
533 "@code{stemRightBeamCount}. "
536 /* accepts */ "beam-forbid-event",
537 /* acks */ "stem-interface rest-interface beam-interface bar-line-interface",
538 /* reads */ "autoBeaming autoBeamSettings beatLength subdivideBeams",