lily/collision-engraver.cc

   1 /*
   2   collision-reg.cc -- implement Collision_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "note-column.hh"
  10 #include "collision.hh"
  11
  12 #include "engraver.hh"
  13 #include "axis-group-interface.hh"
  14
  15 /*
  16   collect Note_column, and as soon as there are 2 or more, put them in
  17   a collision object.  */
  18 class Collision_engraver : public Engraver {
  19   Item * col_p_;
  20   Link_array<Grob> note_column_l_arr_;
  21
  22 protected:
  23   virtual void acknowledge_grob (Grob_info);
  24   virtual void create_grobs ();
  25   virtual void stop_translation_timestep ();
  26 public:
  27   VIRTUAL_COPY_CONS (Translator);
  28   Collision_engraver ();
  29 };
  30
  31
  32 void
  33 Collision_engraver::create_grobs ()
  34 {
  35   if (col_p_ || note_column_l_arr_.size () < 2)
  36     return ;
  37   if (!col_p_)
  38     {
  39       col_p_ = new Item (get_property ("NoteCollision"));
  40       Axis_group_interface::set_interface (col_p_);
  41       Axis_group_interface::set_axes (col_p_, X_AXIS, Y_AXIS);
  42
  43       announce_grob (col_p_,0);
  44     }
  45
  46   for (int i=0; i< note_column_l_arr_.size (); i++)
  47     Collision::add_column (col_p_,note_column_l_arr_[i]);
  48 }
  49
  50 void
  51 Collision_engraver::acknowledge_grob (Grob_info i)
  52 {
  53   if (Note_column::has_interface (i.elem_l_))
  54     {
  55       /*should check Y axis? */
  56       if (Note_column::rest_b (i.elem_l_) || i.elem_l_->parent_l (X_AXIS))
  57         return ;
  58
  59       note_column_l_arr_.push (i.elem_l_);
  60     }
  61 }
  62
  63 void
  64 Collision_engraver::stop_translation_timestep ()
  65 {
  66   if (col_p_)
  67     {
  68       typeset_grob (col_p_);
  69       col_p_ =0;
  70     }
  71   note_column_l_arr_.clear ();
  72 }
  73
  74 Collision_engraver::Collision_engraver ()
  75 {
  76   col_p_ =0;
  77 }
  78
  79
  80
  81 ADD_THIS_TRANSLATOR (Collision_engraver);