lily/arpeggio-engraver.cc

   1 /*
   2   arpeggio-engraver.cc -- implement Arpeggio_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000--2003 Jan Nieuwenhuizen <janneke@gnu.org>
   7  */
   8
   9 #include "engraver.hh"
  10 #include "group-interface.hh"
  11 #include "item.hh"
  12 #include "event.hh"
  13 #include "arpeggio.hh"
  14 #include "stem.hh"
  15 #include "rhythmic-head.hh"
  16 #include "side-position-interface.hh"
  17 #include "note-column.hh"
  18
  19 class Arpeggio_engraver : public Engraver
  20 {
  21 public:
  22   TRANSLATOR_DECLARATIONS(Arpeggio_engraver);
  23 protected:
  24   virtual void acknowledge_grob (Grob_info);
  25   virtual void process_music ();
  26
  27   virtual void stop_translation_timestep ();
  28   virtual bool try_music (Music *);
  29
  30 private:
  31   Item* arpeggio_;
  32   Music *arpeggio_req_;
  33 };
  34
  35 Arpeggio_engraver::Arpeggio_engraver ()
  36 {
  37   arpeggio_ = 0;
  38   arpeggio_req_ = 0;
  39 }
  40
  41 bool
  42 Arpeggio_engraver::try_music (Music* m)
  43 {
  44   if (!arpeggio_req_)
  45     {
  46       arpeggio_req_ = m;
  47     }
  48   return true;
  49 }
  50
  51 void
  52 Arpeggio_engraver::acknowledge_grob (Grob_info info)
  53 {
  54   if (arpeggio_)
  55     {
  56       if (Stem::has_interface (info.grob_))
  57         {
  58           if (!arpeggio_->get_parent  (Y_AXIS))
  59             arpeggio_->set_parent (info.grob_, Y_AXIS);
  60
  61           Pointer_group_interface::add_grob (arpeggio_, ly_symbol2scm ("stems"), info.grob_);
  62         }
  63
  64       /*
  65         We can't catch local key items (accidentals) from Voice context,
  66         see Local_key_engraver
  67       */
  68       else if (Rhythmic_head::has_interface (info.grob_))
  69         {
  70           Side_position_interface::add_support (arpeggio_, info.grob_);
  71         }
  72       else if (Note_column::has_interface (info.grob_ ))
  73         {
  74           info.grob_->set_grob_property ("arpeggio", arpeggio_->self_scm ());
  75         }
  76     }
  77 }
  78
  79 void
  80 Arpeggio_engraver::process_music ()
  81 {
  82   if (arpeggio_req_)
  83     {
  84       arpeggio_ = new Item (get_property ("Arpeggio"));
  85       announce_grob(arpeggio_, arpeggio_req_->self_scm());
  86     }
  87 }
  88
  89 void
  90 Arpeggio_engraver::stop_translation_timestep ()
  91 {
  92   if (arpeggio_)
  93     {
  94       typeset_grob (arpeggio_);
  95       arpeggio_ = 0;
  96     }
  97   arpeggio_req_ = 0;
  98 }
  99
 100
 101
 102
 103 ENTER_DESCRIPTION(Arpeggio_engraver,
 104 /* descr */       "Generate an Arpeggio from a Arpeggio_req",
 105 /* creats*/       "Arpeggio",
 106 /* accepts */     "arpeggio-event",
 107 /* acks  */       "stem-interface rhythmic-head-interface note-column-interface",
 108 /* reads */       "",
 109 /* write */       "");