2 metronome-engraver.cc -- implement Metronome_mark_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1998--2009 Jan Nieuwenhuizen <janneke@gnu.org>
12 #include "engraver.hh"
15 #include "duration.hh"
16 #include "grob-array.hh"
18 #include "stream-event.hh"
19 #include "text-interface.hh"
21 #include "translator.icc"
23 class Metronome_mark_engraver
: public Engraver
26 TRANSLATOR_DECLARATIONS (Metronome_mark_engraver
);
36 virtual void derived_mark () const;
37 void stop_translation_timestep ();
38 void process_music ();
41 Metronome_mark_engraver::Metronome_mark_engraver ()
44 last_duration_
= SCM_EOL
;
45 last_count_
= SCM_EOL
;
50 Metronome_mark_engraver::derived_mark () const
52 scm_gc_mark (last_count_
);
53 scm_gc_mark (last_duration_
);
54 scm_gc_mark (last_text_
);
58 Metronome_mark_engraver::stop_translation_timestep ()
62 Grob
*mc
= unsmob_grob (get_property ("currentMusicalColumn"));
63 text_
->set_parent (mc
, X_AXIS
);
64 text_
->set_object ("side-support-elements",
65 grob_list_to_grob_array (get_property ("stavesFound")));
71 Metronome_mark_engraver::process_music ()
73 SCM count
= get_property ("tempoUnitCount");
74 SCM duration
= get_property ("tempoUnitDuration");
75 SCM text
= get_property ("tempoText");
77 if ( ( (unsmob_duration (duration
) && scm_is_number (count
))
78 || Text_interface::is_markup (text
) )
79 && !(ly_is_equal (count
, last_count_
)
80 && ly_is_equal (duration
, last_duration_
)
81 && ly_is_equal (text
, last_text_
)))
83 text_
= make_item ("MetronomeMark", SCM_EOL
);
85 SCM proc
= get_property ("metronomeMarkFormatter");
86 SCM result
= scm_call_4 (proc
,
90 context ()->self_scm ());
92 text_
->set_property ("text", result
);
95 last_duration_
= duration
;
100 ADD_TRANSLATOR (Metronome_mark_engraver
,
102 "Engrave metronome marking. This delegates the formatting"
103 " work to the function in the @code{metronomeMarkFormatter}"
104 " property. The mark is put over all staves. The staves are"
105 " taken from the @code{stavesFound} property, which is"
106 " maintained by @ref{Staff_collecting_engraver}.",
113 "metronomeMarkFormatter "