lily/rest-engraver.cc

   1 /*
   2   rest-engraver.cc -- implement Rest_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "engraver.hh"
  10
  11 #include "dots.hh"
  12 #include "duration.hh"
  13 #include "item.hh"
  14 #include "pitch.hh"
  15 #include "rhythmic-head.hh"
  16 #include "staff-symbol-referencer.hh"
  17 #include "stream-event.hh"
  18
  19 #include "translator.icc"
  20
  21 class Rest_engraver : public Engraver
  22 {
  23   Stream_event *rest_event_;
  24   Item *dot_;
  25   Grob *rest_;
  26 protected:
  27   void start_translation_timestep ();
  28   void process_music ();
  29   DECLARE_TRANSLATOR_LISTENER (rest);
  30 public:
  31   TRANSLATOR_DECLARATIONS (Rest_engraver);
  32 };
  33
  34 /*
  35   Should merge with Note_head_engraver
  36 */
  37 Rest_engraver::Rest_engraver ()
  38 {
  39   rest_event_ = 0;
  40   rest_ = 0;
  41   dot_ = 0;
  42 }
  43
  44 void
  45 Rest_engraver::start_translation_timestep ()
  46 {
  47   rest_event_ = 0;
  48   rest_ = 0;
  49   dot_ = 0;
  50 }
  51
  52 void
  53 Rest_engraver::process_music ()
  54 {
  55   if (rest_event_ && !rest_)
  56     {
  57       rest_ = make_item ("Rest", rest_event_->self_scm ());
  58       Pitch *p = unsmob_pitch (rest_event_->get_property ("pitch"));
  59
  60       if (p)
  61         {
  62           int pos = p->steps ();
  63           SCM c0 = get_property ("middleCPosition");
  64           if (scm_is_number (c0))
  65             pos += scm_to_int (c0);
  66
  67           rest_->set_property ("staff-position", scm_from_int (pos));
  68         }
  69     }
  70 }
  71
  72 IMPLEMENT_TRANSLATOR_LISTENER (Rest_engraver, rest);
  73 void
  74 Rest_engraver::listen_rest (Stream_event *ev)
  75 {
  76   ASSIGN_EVENT_ONCE (rest_event_, ev);
  77 }
  78
  79 ADD_TRANSLATOR (Rest_engraver,
  80                 /* doc */
  81                 "Engrave rests.",
  82
  83                 /* create */
  84                 "Rest ",
  85
  86                 /* read */
  87                 "middleCPosition ",
  88
  89                 /* write */
  90                 ""
  91                 );