lily/note-spacing-engraver.cc

   1 /*
   2   note-spacing-engraver.cc -- implement Note_spacing_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2006 Han-Wen Nienhuys <hanwen@lilypond.org>
   7
   8 */
   9
  10 #include "engraver.hh"
  11
  12 #include "context.hh"
  13 #include "item.hh"
  14 #include "pointer-group-interface.hh"
  15
  16 #include "translator.icc"
  17
  18 class Note_spacing_engraver : public Engraver
  19 {
  20   Grob *last_spacing_;
  21   Context *last_spacing_parent_context_;
  22
  23   Grob *spacing_;
  24
  25   void add_spacing_item (Grob *);
  26   TRANSLATOR_DECLARATIONS (Note_spacing_engraver);
  27 protected:
  28
  29   DECLARE_ACKNOWLEDGER (rhythmic_grob);
  30   DECLARE_ACKNOWLEDGER (note_column);
  31   void stop_translation_timestep ();
  32   virtual void finalize ();
  33   virtual void derived_mark () const;
  34 };
  35
  36 void
  37 Note_spacing_engraver::derived_mark () const
  38 {
  39   if (last_spacing_parent_context_)
  40     scm_gc_mark (last_spacing_parent_context_->self_scm ());
  41 }
  42
  43 Note_spacing_engraver::Note_spacing_engraver ()
  44 {
  45   last_spacing_parent_context_ = 0;
  46   last_spacing_ = 0;
  47   spacing_ = 0;
  48 }
  49
  50 void
  51 Note_spacing_engraver::add_spacing_item (Grob *g)
  52 {
  53   if (!spacing_)
  54     {
  55       spacing_ = make_item ("NoteSpacing", g->self_scm ());
  56     }
  57
  58   if (spacing_)
  59     {
  60       Pointer_group_interface::add_grob (spacing_,
  61                                          ly_symbol2scm ("left-items"),
  62                                          g);
  63
  64       if (last_spacing_)
  65         Pointer_group_interface::add_grob (last_spacing_,
  66                                            ly_symbol2scm ("right-items"),
  67                                            g);
  68     }
  69 }
  70
  71
  72 void
  73 Note_spacing_engraver::acknowledge_note_column (Grob_info gi)
  74 {
  75   add_spacing_item (gi.grob ());
  76 }
  77
  78 void
  79 Note_spacing_engraver::acknowledge_rhythmic_grob (Grob_info gi)
  80 {
  81   add_spacing_item (gi.grob ());
  82 }
  83
  84 void
  85 Note_spacing_engraver::finalize ()
  86 {
  87   if (last_spacing_
  88       && last_spacing_parent_context_
  89       && last_spacing_parent_context_ == context ()->get_parent_context ())
  90     {
  91       SCM ccol = get_property ("currentCommandColumn");
  92       Grob *column = unsmob_grob (ccol);
  93
  94       Pointer_group_interface::add_grob (last_spacing_,
  95                                          ly_symbol2scm ("right-items"),
  96                                          column);
  97     }
  98 }
  99
 100 void
 101 Note_spacing_engraver::stop_translation_timestep ()
 102 {
 103   if (last_spacing_
 104       && last_spacing_parent_context_
 105       && last_spacing_parent_context_ == context ()->get_parent_context ())
 106     {
 107       Grob *sep = unsmob_grob (get_property ("breakableSeparationItem"));
 108       if (sep)
 109         Pointer_group_interface::add_grob (last_spacing_,
 110                                            ly_symbol2scm ("right-items"),
 111                                            sep);
 112     }
 113
 114   if (spacing_)
 115     {
 116       last_spacing_ = spacing_;
 117       last_spacing_parent_context_ = context ()->get_parent_context ();
 118       spacing_ = 0;
 119     }
 120
 121 }
 122
 123 ADD_ACKNOWLEDGER (Note_spacing_engraver, note_column);
 124 ADD_ACKNOWLEDGER (Note_spacing_engraver, rhythmic_grob);
 125
 126 ADD_TRANSLATOR (Note_spacing_engraver,
 127                 /* doc */ "Generates NoteSpacing, an object linking horizontal lines for use in spacing.",
 128                 /* create */ "NoteSpacing",
 129                 /* read */ "",
 130                 /* write */ "");