lily/breathing-sign-engraver.cc

   1 /*
   2   breathing_sign-engraver.cc -- implement Breathing_sign_engraver
   3
   4   Copyright (C) 1999 Michael Krause
   5
   6   written for the GNU LilyPond music typesetter
   7
   8 TODO:
   9
  10   . Cancel any beams running through the breathing sign
  11  ([e8 \breathe f e f] should become [e8] \breathe [f e f])
  12   . Spacing is not yet completely pretty
  13
  14 */
  15
  16 #include "staff-symbol-referencer.hh"
  17 #include "breathing-sign.hh"
  18 #include "event.hh"
  19
  20 #include "engraver-group-engraver.hh"
  21 #include "item.hh"
  22 #include "engraver.hh"
  23
  24
  25 class Breathing_sign_engraver : public Engraver {
  26 public:
  27   TRANSLATOR_DECLARATIONS(Breathing_sign_engraver);
  28
  29 protected:
  30   virtual bool try_music (Music *req);
  31   virtual void process_acknowledged_grobs ();
  32   virtual void stop_translation_timestep ();
  33   virtual void start_translation_timestep ();
  34
  35 private:
  36   Music * breathing_sign_req_;
  37   Grob * breathing_sign_;
  38 };
  39
  40 Breathing_sign_engraver::Breathing_sign_engraver ()
  41 {
  42   breathing_sign_ = 0;
  43   breathing_sign_req_ = 0;
  44 }
  45
  46 bool
  47 Breathing_sign_engraver::try_music (Music*r)
  48 {
  49   breathing_sign_req_ = r;
  50   return true;
  51 }
  52
  53 void
  54 Breathing_sign_engraver::process_acknowledged_grobs ()
  55 {
  56   if (breathing_sign_req_ && ! breathing_sign_)
  57     {
  58       SCM b = get_property ("BreathingSign");
  59       breathing_sign_ = new Item (b);
  60
  61       announce_grob(breathing_sign_, breathing_sign_req_->self_scm());
  62       breathing_sign_req_ = 0;
  63     }
  64 }
  65
  66 void
  67 Breathing_sign_engraver::stop_translation_timestep ()
  68 {
  69   if (breathing_sign_)
  70     {
  71       typeset_grob (breathing_sign_);
  72       breathing_sign_ = 0;
  73     }
  74 }
  75
  76 void
  77 Breathing_sign_engraver::start_translation_timestep ()
  78 {
  79   breathing_sign_req_ = 0;
  80 }
  81
  82
  83 ENTER_DESCRIPTION(Breathing_sign_engraver,
  84 /* descr */       "",
  85 /* creats*/       "BreathingSign",
  86 /* accepts */     "breathing-event",
  87 /* acks  */      "",
  88 /* reads */       "",
  89 /* write */       "");