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--2004 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "audio-item.hh"
  10 #include "performer.hh"
  11
  12 class Time_signature_performer : public Performer
  13 {
  14 public:
  15   TRANSLATOR_DECLARATIONS (Time_signature_performer);
  16   ~Time_signature_performer ();
  17
  18 protected:
  19
  20   virtual void stop_translation_timestep ();
  21   virtual void create_audio_elements ();
  22
  23   SCM prev_fraction_;
  24 private:
  25
  26   Audio_time_signature* audio_;
  27 };
  28
  29
  30 Time_signature_performer::Time_signature_performer ()
  31 {
  32   prev_fraction_ = SCM_BOOL_F;
  33   audio_ = 0;
  34 }
  35
  36 Time_signature_performer::~Time_signature_performer ()
  37 {
  38 }
  39
  40
  41 void
  42 Time_signature_performer::create_audio_elements ()
  43 {
  44   SCM fr = get_property ("timeSignatureFraction");
  45   if (scm_is_pair (fr) && !ly_c_equal_p (fr, prev_fraction_))
  46     {
  47       prev_fraction_ = fr;
  48       int b = scm_to_int (scm_car (fr));
  49       int o = scm_to_int (scm_cdr (fr));
  50
  51       audio_ = new Audio_time_signature (b,o);
  52       Audio_element_info info (audio_, 0);
  53       announce_element (info);
  54
  55     }
  56 }
  57
  58 void
  59 Time_signature_performer::stop_translation_timestep ()
  60 {
  61   if (audio_)
  62     {
  63       play_element (audio_);
  64       audio_ = 0;
  65     }
  66 }
  67
  68 ENTER_DESCRIPTION (Time_signature_performer,"","","","","","");