lily/rhythmic-column-engraver.cc

   1 /*
   2   rhythmic-column-grav.cc -- implement Rhythmic_column_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #include "slur.hh"
  11 #include "engraver.hh"
  12 #include "rhythmic-head.hh"
  13 #include "stem.hh"
  14 #include "note-column.hh"
  15 #include "dot-column.hh"
  16 #include "event.hh"
  17 #include "item.hh"
  18 #include "group-interface.hh"
  19
  20
  21
  22 /*
  23   this engraver  glues together stems, rests and note heads into a NoteColumn
  24   grob.
  25
  26   It also generates spacing objects.  Originally, we have tried to
  27   have the spacing functionality at different levels.
  28
  29   - by simply using the sequence of Separation-item as
  30   spacing-sequences (at staff level). Unfortunately, this fucks up if
  31   there are different kinds of tuplets in different voices (8th and
  32   8ths triplets combined made the program believe there were 1/12 th
  33   notes.).
  34
  35   Doing it in a separate engraver using timing info is generally
  36   complicated (start/end time management), and fucks up if a voice
  37   changes staff.
  38
  39   Now we do it from here again. This has the problem that voices can
  40   appear and disappear at will, leaving lots of loose ends (the note
  41   spacing engraver don't know where to connect the last note of the
  42   voice on the right with), but we don't complain about those, and let
  43   the default spacing do its work.
  44
  45  */
  46
  47
  48 class Rhythmic_column_engraver :public Engraver
  49 {
  50   Link_array<Grob> rheads_;
  51   Grob * stem_;
  52   Grob * note_column_;
  53   Grob * dotcol_;
  54
  55   Grob * last_spacing_;
  56   Grob * spacing_;
  57
  58   TRANSLATOR_DECLARATIONS (Rhythmic_column_engraver);
  59 protected:
  60
  61   virtual void acknowledge_grob (Grob_info);
  62   virtual void process_acknowledged_grobs ();
  63   virtual void stop_translation_timestep ();
  64 };
  65
  66
  67
  68 Rhythmic_column_engraver::Rhythmic_column_engraver ()
  69 {
  70   spacing_ =0 ;
  71   last_spacing_ = 0;
  72
  73   stem_ =0;
  74   note_column_=0;
  75   dotcol_ =0;
  76 }
  77
  78
  79 void
  80 Rhythmic_column_engraver::process_acknowledged_grobs ()
  81 {
  82   if (rheads_.size ())
  83     {
  84       if (!note_column_)
  85         {
  86           note_column_ = make_item ("NoteColumn",rheads_[0]->self_scm ());
  87
  88           spacing_ = make_item ("NoteSpacing", SCM_EOL);
  89           spacing_->set_property ("left-items", scm_cons (note_column_->self_scm (), SCM_EOL));
  90
  91
  92
  93
  94           if (last_spacing_)
  95             {
  96               Pointer_group_interface::add_grob (last_spacing_,
  97                                                  ly_symbol2scm ("right-items" ),
  98                                                  note_column_);
  99             }
 100
 101         }
 102
 103       for (int i=0; i < rheads_.size (); i++)
 104         {
 105           if (!rheads_[i]->get_parent (X_AXIS))
 106             Note_column::add_head (note_column_, rheads_[i]);
 107         }
 108       rheads_.set_size (0);
 109     }
 110
 111
 112   if (note_column_)
 113     {
 114       if (dotcol_
 115           && !dotcol_->get_parent (X_AXIS))
 116         {
 117           Note_column::set_dotcol (note_column_, dotcol_);
 118         }
 119
 120       if (stem_
 121           && !stem_->get_parent (X_AXIS))
 122         {
 123           Note_column::set_stem (note_column_, stem_);
 124           stem_ = 0;
 125         }
 126
 127     }
 128 }
 129
 130 void
 131 Rhythmic_column_engraver::acknowledge_grob (Grob_info i)
 132 {
 133   Item * item =  dynamic_cast <Item *> (i.grob_);
 134   if (!item || item->get_parent (X_AXIS))
 135     return ;
 136   if (Stem::has_interface (item))
 137     {
 138       stem_ = item;
 139     }
 140   else if (Rhythmic_head::has_interface (item))
 141     {
 142       rheads_.push (item);
 143     }
 144   else if (Dot_column::has_interface (item))
 145     {
 146       dotcol_ = item;
 147     }
 148 }
 149
 150 void
 151 Rhythmic_column_engraver::stop_translation_timestep ()
 152 {
 153       note_column_ =0;
 154
 155   if (spacing_)
 156     {
 157       last_spacing_ = spacing_;
 158       spacing_ =0;
 159     }
 160
 161   dotcol_ =0;
 162   stem_ =0;
 163 }
 164
 165
 166
 167 ENTER_DESCRIPTION (Rhythmic_column_engraver,
 168 /* descr */       "Generates NoteColumn, an objects that groups stems, noteheads and rests.",
 169 /* creats*/       "NoteColumn NoteSpacing",
 170 /* accepts */     "",
 171 /* acks  */      "stem-interface rhythmic-head-interface dot-column-interface",
 172 /* reads */       "",
 173 /* write */       "");