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--2002 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 "musical-request.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   virtual void start_translation_timestep ();
  65 };
  66
  67
  68
  69 Rhythmic_column_engraver::Rhythmic_column_engraver ()
  70 {
  71   spacing_ =0 ;
  72   last_spacing_ = 0;
  73
  74   stem_ =0;
  75   note_column_=0;
  76   dotcol_ =0;
  77 }
  78
  79
  80 void
  81 Rhythmic_column_engraver::process_acknowledged_grobs ()
  82 {
  83   if (rheads_.size ())
  84     {
  85       if (!note_column_)
  86         {
  87           note_column_ = new Item (get_property ("NoteColumn"));
  88           announce_grob(note_column_, SCM_EOL);
  89
  90
  91          spacing_ = new Item (get_property ("NoteSpacing"));
  92          spacing_->set_grob_property ("left-items", gh_cons (note_column_->self_scm (), SCM_EOL));
  93
  94          /*
  95            Should insert a cause. Collision warnings go into the  void.
  96
  97           */
  98          announce_grob(spacing_, SCM_EOL);
  99
 100          if (last_spacing_)
 101            {
 102              Pointer_group_interface::add_grob (last_spacing_,
 103                                                 ly_symbol2scm ("right-items" ),
 104                                                 note_column_);
 105            }
 106
 107         }
 108
 109       for (int i=0; i < rheads_.size (); i++)
 110         {
 111           if (!rheads_[i]->get_parent (X_AXIS))
 112             Note_column::add_head (note_column_, rheads_[i]);
 113         }
 114       rheads_.set_size (0);
 115     }
 116
 117
 118   if (note_column_)
 119     {
 120       if (dotcol_
 121           && !dotcol_->get_parent (X_AXIS))
 122         {
 123           Note_column::set_dotcol (note_column_, dotcol_);
 124         }
 125
 126       if (stem_
 127           && !stem_->get_parent (X_AXIS))
 128         {
 129           Note_column::set_stem (note_column_, stem_);
 130           stem_ = 0;
 131         }
 132
 133     }
 134 }
 135
 136 void
 137 Rhythmic_column_engraver::acknowledge_grob (Grob_info i)
 138 {
 139   Item * item =  dynamic_cast <Item *> (i.grob_);
 140   if (!item || item->get_parent (X_AXIS))
 141     return ;
 142   if (Stem::has_interface (item))
 143     {
 144       stem_ = item;
 145     }
 146   else if (Rhythmic_head::has_interface (item))
 147     {
 148       rheads_.push (item);
 149     }
 150   else if (Dot_column::has_interface (item))
 151     {
 152       dotcol_ = item;
 153     }
 154 }
 155
 156 void
 157 Rhythmic_column_engraver::stop_translation_timestep ()
 158 {
 159   if (note_column_)
 160     {
 161       typeset_grob (note_column_);
 162       note_column_ =0;
 163     }
 164
 165   if (spacing_)
 166     {
 167       typeset_grob (spacing_);
 168       last_spacing_ = spacing_;
 169       spacing_ =0;
 170     }
 171 }
 172
 173 void
 174 Rhythmic_column_engraver::start_translation_timestep ()
 175 {
 176   dotcol_ =0;
 177   stem_ =0;
 178 }
 179
 180
 181
 182 ENTER_DESCRIPTION(Rhythmic_column_engraver,
 183 /* descr */       "Generates NoteColumn, an objects that groups stems, noteheads and rests.",
 184 /* creats*/       "NoteColumn NoteSpacing",
 185 /* acks  */       "stem-interface rhythmic-head-interface dot-column-interface",
 186 /* reads */       "",
 187 /* write */       "");