lily/rest-collision-engraver.cc

   1 /*
   2   rest-collision-engraver.cc -- implement Rest_collision_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "warn.hh"
  10 #include "engraver.hh"
  11 #include "rest-collision.hh"
  12 #include "note-column.hh"
  13 #include "item.hh"
  14
  15 class Rest_collision_engraver : public Engraver
  16 {
  17   Item *rest_collision_;
  18   vsize rest_count_;
  19   vector<Grob*> note_columns_;
  20 protected:
  21   DECLARE_ACKNOWLEDGER (note_column);
  22   void process_acknowledged ();
  23   void stop_translation_timestep ();
  24 public:
  25   TRANSLATOR_DECLARATIONS (Rest_collision_engraver);
  26 };
  27
  28 Rest_collision_engraver::Rest_collision_engraver ()
  29 {
  30   rest_collision_ = 0;
  31   rest_count_ = 0;
  32 }
  33
  34 void
  35 Rest_collision_engraver::process_acknowledged ()
  36 {
  37   if (rest_collision_
  38       || note_columns_.empty ()
  39       || !rest_count_
  40       || (note_columns_.size () == rest_count_
  41           && rest_count_ < 2))
  42     return;
  43
  44   rest_collision_ = make_item ("RestCollision", SCM_EOL);
  45
  46   for (vsize i = 0; i < note_columns_.size (); i++)
  47     Rest_collision::add_column (rest_collision_, note_columns_[i]);
  48 }
  49
  50 void
  51 Rest_collision_engraver::acknowledge_note_column (Grob_info i)
  52 {
  53   note_columns_.push_back (i.grob ());
  54   if (Note_column::has_rests (i.grob ()))
  55     rest_count_++;
  56 }
  57
  58 void
  59 Rest_collision_engraver::stop_translation_timestep ()
  60 {
  61   rest_collision_ = 0;
  62   note_columns_.clear ();
  63   rest_count_ = 0;
  64 }
  65
  66 #include "translator.icc"
  67
  68 ADD_ACKNOWLEDGER (Rest_collision_engraver, note_column);
  69 ADD_TRANSLATOR (Rest_collision_engraver,
  70                 /* doc */
  71                 "Handle collisions of rests.",
  72
  73                 /* create */
  74                 "RestCollision ",
  75
  76                 /* read */
  77                 "",
  78
  79                 /* write */
  80                 ""
  81                 );