lily/melisma-translator.cc

   1 /*
   2   melisma-engraver.cc --  implement Melisma_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1999--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 /*
  11   duplicated in melisma-performer
  12  */
  13 #include "engraver.hh"
  14 #include "event.hh"
  15 #include "grob.hh"
  16 #include "context.hh"
  17
  18
  19 /**
  20    Signal existence of melismas.
  21  */
  22 class Melisma_translator : public Translator
  23 {
  24 public:
  25   TRANSLATOR_DECLARATIONS (Melisma_translator);
  26 protected:
  27   virtual bool try_music (Music *);
  28   virtual void process_music ();
  29   virtual void start_translation_timestep ();
  30   Music * event_;
  31 };
  32
  33
  34 bool
  35 Melisma_translator::try_music (Music *m)
  36 {
  37   if (m->is_mus_type ("melisma-playing-event"))
  38     {
  39       return melisma_busy (daddy_context_);
  40     }
  41   else if (m->is_mus_type ("melisma-span-event"))
  42     {
  43       event_ = m;
  44       return true;
  45     }
  46
  47   return false;
  48 }
  49
  50 void
  51 Melisma_translator::process_music ()
  52 {
  53   if (event_)
  54     {
  55       SCM sd = event_->get_property ("span-direction");
  56       Direction d = to_dir (sd);
  57       if (d == START)
  58         daddy_context_->set_property ("melismaBusy", SCM_BOOL_T);
  59       else
  60         daddy_context_->unset_property (ly_symbol2scm ("melismaBusy"));
  61     }
  62
  63 }
  64
  65 void
  66 Melisma_translator::start_translation_timestep ()
  67 {
  68   event_ = 0;
  69 }
  70
  71 Melisma_translator::Melisma_translator ()
  72 {
  73   event_ = 0;
  74 }
  75
  76 ENTER_DESCRIPTION (Melisma_translator,
  77 /* descr */       "This translator collects melisma information about ties, beams, and user settings (@code{melismaBusy}, and signals it to the @code{\addlyrics} code.  ",
  78 /* creats*/       "",
  79 /* accepts */     "melisma-playing-event melisma-span-event",
  80 /* acks  */      "",
  81 /* reads */       "melismaBusy melismaBusyProperties slurMelismaBusy tieMelismaBusy beamMelismaBusy",
  82 /* write */       "");