lily/time-signature-performer.cc

   1 /*
   2   time-signature-performer.cc -- implement Time_signature_performer
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "audio-item.hh"
  10 #include "lily-proto.hh"
  11 #include "performer.hh"
  12
  13
  14 class Time_signature_performer : public Performer
  15 {
  16 public:
  17   TRANSLATOR_DECLARATIONS(Time_signature_performer);
  18   ~Time_signature_performer ();
  19
  20 protected:
  21
  22   virtual void stop_translation_timestep ();
  23   virtual void create_audio_elements ();
  24
  25   SCM prev_fraction_;
  26 private:
  27
  28   Audio_time_signature* audio_p_;
  29 };
  30
  31
  32 Time_signature_performer::Time_signature_performer ()
  33 {
  34   prev_fraction_ = SCM_BOOL_F;
  35   audio_p_ = 0;
  36 }
  37
  38 Time_signature_performer::~Time_signature_performer ()
  39 {
  40 }
  41
  42
  43 void
  44 Time_signature_performer::create_audio_elements ()
  45 {
  46   SCM fr = get_property ("timeSignatureFraction");
  47   if (gh_pair_p (fr) && !gh_equal_p (fr, prev_fraction_))
  48     {
  49       prev_fraction_ = fr;
  50       int b = gh_scm2int (ly_car (fr));
  51       int o = gh_scm2int (ly_cdr (fr));
  52
  53       audio_p_ = new Audio_time_signature (b,o);
  54       Audio_element_info info (audio_p_, 0);
  55       announce_element (info);
  56
  57     }
  58 }
  59
  60 void
  61 Time_signature_performer::stop_translation_timestep ()
  62 {
  63   if (audio_p_)
  64     {
  65       play_element (audio_p_);
  66       audio_p_ = 0;
  67     }
  68 }
  69
  70 ENTER_DESCRIPTION (Time_signature_performer, "","","","","" );