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--2006 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
  14 class Rest_collision_engraver : public Engraver
  15 {
  16   Item *rest_collision_;
  17   vsize rest_count_;
  18   Link_array__Grob_ note_columns_;
  19 protected:
  20   DECLARE_ACKNOWLEDGER (note_column);
  21   void process_acknowledged ();
  22   void stop_translation_timestep ();
  23 public:
  24   TRANSLATOR_DECLARATIONS (Rest_collision_engraver);
  25 };
  26
  27 Rest_collision_engraver::Rest_collision_engraver ()
  28 {
  29   rest_collision_ = 0;
  30   rest_count_ = 0;
  31 }
  32
  33 void
  34 Rest_collision_engraver::process_acknowledged ()
  35 {
  36   if (rest_collision_
  37       || note_columns_.empty ()
  38       || !rest_count_
  39       || (note_columns_.size () == rest_count_
  40           && rest_count_ < 2))
  41     return;
  42
  43   rest_collision_ = make_item ("RestCollision", SCM_EOL);
  44
  45   for (vsize i = 0; i < note_columns_.size (); i++)
  46     Rest_collision::add_column (rest_collision_, note_columns_[i]);
  47 }
  48
  49 void
  50 Rest_collision_engraver::acknowledge_note_column (Grob_info i)
  51 {
  52   note_columns_.push_back (i.grob ());
  53   if (Note_column::has_rests (i.grob ()))
  54     rest_count_++;
  55 }
  56
  57 void
  58 Rest_collision_engraver::stop_translation_timestep ()
  59 {
  60   rest_collision_ = 0;
  61   note_columns_.clear ();
  62   rest_count_ = 0;
  63 }
  64
  65 #include "translator.icc"
  66
  67 ADD_ACKNOWLEDGER (Rest_collision_engraver, note_column);
  68 ADD_TRANSLATOR (Rest_collision_engraver,
  69                 /* doc */ "Handles collisions of rests.",
  70                 /* create */ "RestCollision",
  71                 /* accept */ "",
  72                 /* read */ "",
  73                 /* write */ "");