2 new-chord-tremolo-engraver.cc -- implement Chord_tremolo_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 2000--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
10 #include "engraver.hh"
12 #include "repeated-music.hh"
14 #include "rhythmic-head.hh"
15 #include "engraver-group-engraver.hh"
19 #include "note-head.hh"
22 #include "chord-tremolo-iterator.hh"
23 #include "stem-tremolo.hh"
24 #include "music-list.hh"
25 #include "math.h" // ceil
29 This acknowledges repeated music with "tremolo" style. It typesets
34 - perhaps use engraver this to steer other engravers? That would
35 create dependencies between engravers, which is bad.
37 - create dots if appropriate.
39 - create TremoloBeam iso Beam?
42 class Chord_tremolo_engraver : public Engraver
45 TRANSLATOR_DECLARATIONS (Chord_tremolo_engraver);
47 Repeated_music * repeat_;
49 /// moment (global time) where beam started.
53 int total_duration_flags_;
55 /// location within measure where beam started.
56 Moment beam_start_location_;
58 bool sequential_body_b_;
60 Spanner * finished_beam_;
63 virtual void finalize ();
64 virtual bool try_music (Music*);
65 virtual void acknowledge_grob (Grob_info);
66 virtual void stop_translation_timestep ();
67 virtual void start_translation_timestep ();
68 virtual void process_music ();
71 Chord_tremolo_engraver::Chord_tremolo_engraver ()
73 beam_ = finished_beam_ = 0;
77 sequential_body_b_ = false;
81 Chord_tremolo_engraver::try_music (Music * m)
83 Repeated_music * rp = dynamic_cast<Repeated_music*> (m);
85 && rp->get_property ("iterator-ctor") == Chord_tremolo_iterator::constructor_proc
88 Moment l = rp->get_length ();
90 start_mom_ = now_mom ();
91 stop_mom_ = start_mom_ + l;
93 Sequential_music * seq = dynamic_cast<Sequential_music*> (rp->body ());
94 sequential_body_b_ = seq;
96 int elt_count = seq ? scm_ilength (seq-> music_list ()) : 1;
98 if (seq && elt_count != 2)
100 rp->origin ()->warning (_f ("Chord tremolo with %d elements. Must have two elements.", elt_count));
106 Rational total_dur = l.main_part_;
107 Rational note_dur = total_dur / Rational (elt_count * repeat_->repeat_count ());
109 total_duration_flags_ = 0 >? (intlog2 (total_dur.den ()) - 2);
111 flags_ = intlog2 (note_dur.den ()) -2 ;
120 Chord_tremolo_engraver::process_music ()
122 if (repeat_ && sequential_body_b_ && !beam_)
124 beam_ = make_spanner ("Beam");
125 beam_->set_property ("chord-tremolo", SCM_BOOL_T);
127 SCM smp = get_property ("measurePosition");
129 = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
130 beam_start_location_ = mp;
131 announce_grob (beam_, repeat_->self_scm ());
136 Chord_tremolo_engraver::finalize ()
141 repeat_->origin ()->warning (_ ("unterminated chord tremolo"));
147 Chord_tremolo_engraver::typeset_beam ()
151 typeset_grob (finished_beam_);
157 Chord_tremolo_engraver::acknowledge_grob (Grob_info info)
159 if (beam_ && Stem::has_interface (info.grob_))
161 Grob * s = info.grob_;
163 if (start_mom_ == now_mom ())
164 Stem::set_beaming (s, flags_, RIGHT);
166 Stem::set_beaming (s, flags_, LEFT);
168 if (Stem::duration_log (s) != 1)
170 beam_->set_property ("gap-count", scm_int2num (flags_ - total_duration_flags_));
173 if (info.music_cause ()->is_mus_type ("rhythmic-event"))
175 Beam::add_stem (beam_, s);
179 String s = _ ("stem must have Rhythmic structure");
180 if (info.music_cause ())
181 info.music_cause ()->origin ()->warning (s);
187 flags_ && !sequential_body_b_ && Stem::has_interface (info.grob_))
189 stem_tremolo_ = make_item ("StemTremolo");
190 announce_grob (stem_tremolo_, repeat_->self_scm ());
191 stem_tremolo_->set_property ("flag-count",
192 scm_int2num (flags_));
193 stem_tremolo_->set_property ("stem",
194 info.grob_->self_scm ());
195 stem_tremolo_->set_parent (info.grob_, X_AXIS);
201 Chord_tremolo_engraver::start_translation_timestep ()
203 if (beam_ && stop_mom_ == now_mom ())
205 finished_beam_ = beam_;
213 Chord_tremolo_engraver::stop_translation_timestep ()
219 typeset_grob (stem_tremolo_);
226 ENTER_DESCRIPTION (Chord_tremolo_engraver,
227 /* descr */ "Generates beams for tremolo repeats.",
229 /* accepts */ "repeated-music",
230 /* acks */ "stem-interface note-head-interface",