2 time-signature-engraver.cc -- implement Time_signature_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
9 #include "time-signature.hh"
12 #include "engraver.hh"
13 #include "engraver-group-engraver.hh"
17 generate time_signatures.
19 class Time_signature_engraver
: public Engraver
21 Item
*time_signature_
;
22 SCM last_time_fraction_
;
25 virtual void stop_translation_timestep ();
26 virtual void process_music ();
28 TRANSLATOR_DECLARATIONS (Time_signature_engraver
);
32 Time_signature_engraver::Time_signature_engraver ()
35 last_time_fraction_
= SCM_BOOL_F
;
39 Time_signature_engraver::process_music ()
42 not rigorously safe, since the value might get GC'd and
43 reallocated in the same spot */
44 SCM fr
= get_property ("timeSignatureFraction");
46 && last_time_fraction_
!= fr
49 int den
= ly_scm2int (ly_cdr (fr
));
50 if (den
!= (1 << intlog2 (den
)))
53 Todo: should make typecheck?
55 OTOH, Tristan Keuris writes 8/20 in his Intermezzi.
57 warning (_f ("Found strange time signature %d/%d.",
59 ly_scm2int (ly_car (fr
))
64 last_time_fraction_
= fr
;
65 time_signature_
= make_item ("TimeSignature",SCM_EOL
);
66 time_signature_
->set_property ("fraction",fr
);
71 Time_signature_engraver::stop_translation_timestep ()
77 ENTER_DESCRIPTION (Time_signature_engraver
,
78 /* descr */ "Create a TimeSignature whenever @code{timeSignatureFraction} changes",
79 /* creats*/ "TimeSignature",