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--2005 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "engraver.hh"
  10 #include "group-interface.hh"
  11 #include "arpeggio.hh"
  12 #include "stem.hh"
  13 #include "rhythmic-head.hh"
  14 #include "side-position-interface.hh"
  15 #include "note-column.hh"
  16
  17 class Arpeggio_engraver : public Engraver
  18 {
  19 public:
  20   TRANSLATOR_DECLARATIONS (Arpeggio_engraver);
  21
  22 protected:
  23   virtual void acknowledge_grob (Grob_info);
  24   virtual void process_music ();
  25   virtual void stop_translation_timestep ();
  26   virtual bool try_music (Music *);
  27 private:
  28   Item *arpeggio_;
  29   Music *arpeggio_req_;
  30 };
  31
  32 Arpeggio_engraver::Arpeggio_engraver ()
  33 {
  34   arpeggio_ = 0;
  35   arpeggio_req_ = 0;
  36 }
  37
  38 bool
  39 Arpeggio_engraver::try_music (Music *m)
  40 {
  41   if (!arpeggio_req_)
  42     {
  43       arpeggio_req_ = m;
  44     }
  45   return true;
  46 }
  47
  48 void
  49 Arpeggio_engraver::acknowledge_grob (Grob_info info)
  50 {
  51   if (arpeggio_)
  52     {
  53       if (Stem::has_interface (info.grob ()))
  54         {
  55           if (!arpeggio_->get_parent (Y_AXIS))
  56             arpeggio_->set_parent (info.grob (), Y_AXIS);
  57
  58           Pointer_group_interface::add_grob (arpeggio_,
  59                                              ly_symbol2scm ("stems"),
  60                                              info.grob ());
  61         }
  62
  63       /*
  64         We can't catch local key items (accidentals) from Voice context,
  65         see Local_key_engraver
  66       */
  67       else if (Rhythmic_head::has_interface (info.grob ()))
  68         {
  69           Side_position_interface::add_support (arpeggio_, info.grob ());
  70         }
  71       else if (Note_column::has_interface (info.grob ()))
  72         {
  73           info.grob ()->set_property ("arpeggio", arpeggio_->self_scm ());
  74         }
  75     }
  76 }
  77
  78 void
  79 Arpeggio_engraver::process_music ()
  80 {
  81   if (arpeggio_req_)
  82     {
  83       arpeggio_ = make_item ("Arpeggio", arpeggio_req_->self_scm ());
  84     }
  85 }
  86
  87 void
  88 Arpeggio_engraver::stop_translation_timestep ()
  89 {
  90   arpeggio_ = 0;
  91   arpeggio_req_ = 0;
  92 }
  93
  94 ADD_TRANSLATOR (Arpeggio_engraver,
  95                 /* descr */ "Generate an Arpeggio from a Arpeggio_req",
  96                 /* creats*/ "Arpeggio",
  97                 /* accepts */ "arpeggio-event",
  98                 /* acks  */ "stem-interface rhythmic-head-interface note-column-interface",
  99                 /* reads */ "",
 100                 /* write */ "");