lily/rest-collision-engraver.cc

   1 /*
   2   rest-collision-reg.cc -- implement Rest_collision_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "warn.hh"
  10 #include "rest-collision.hh"
  11 #include "engraver.hh"
  12 #include "note-collision.hh"
  13 #include "note-column.hh"
  14
  15 class Rest_collision_engraver : public Engraver
  16 {
  17   Item* rest_collision_;
  18
  19   Link_array<Grob> note_columns_;
  20 protected:
  21   virtual void acknowledge_grob (Grob_info);
  22   virtual void process_acknowledged_grobs ();
  23   virtual void stop_translation_timestep ();
  24 public:
  25   TRANSLATOR_DECLARATIONS(Rest_collision_engraver);
  26 };
  27
  28
  29
  30 Rest_collision_engraver::Rest_collision_engraver ()
  31 {
  32   rest_collision_ =0;
  33 }
  34
  35 void
  36 Rest_collision_engraver::process_acknowledged_grobs ()
  37 {
  38   if (rest_collision_ || note_columns_.size () < 2)
  39     return;
  40
  41   rest_collision_ = new Item (get_property ("RestCollision"));
  42
  43   announce_grob(rest_collision_, SCM_EOL);
  44   for (int i=0; i< note_columns_.size (); i++)
  45     Rest_collision::add_column (rest_collision_,note_columns_[i]);
  46 }
  47
  48 void
  49 Rest_collision_engraver::acknowledge_grob (Grob_info i)
  50 {
  51   if (Note_column::has_interface (i.grob_))
  52     note_columns_.push (i.grob_);
  53 }
  54
  55 void
  56 Rest_collision_engraver::stop_translation_timestep ()
  57 {
  58   if (rest_collision_)
  59     {
  60       typeset_grob (rest_collision_);
  61       rest_collision_ = 0;
  62     }
  63   note_columns_.clear ();
  64 }
  65 ENTER_DESCRIPTION(Rest_collision_engraver,
  66 /* descr */       "Handles collisions of rests.",
  67 /* creats*/       "RestCollision",
  68 /* accepts */     "",
  69 /* acks  */      "note-column-interface",
  70 /* reads */       "",
  71 /* write */       "");