lily/separating-line-group-engraver.cc

   1 /*
   2   separating-line-group-engraver.cc -- implement Separating_line_group_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "engraver.hh"
  10
  11 #include "separating-group-spanner.hh"
  12 #include "separation-item.hh"
  13 #include "paper-column.hh"
  14 #include "output-def.hh"
  15 #include "axis-group-interface.hh"
  16 #include "note-spacing.hh"
  17 #include "accidental-placement.hh"
  18 #include "context.hh"
  19 #include "grob-array.hh"
  20 #include "pointer-group-interface.hh"
  21
  22 #include "translator.icc"
  23
  24 struct Spacings
  25 {
  26   Item *staff_spacing_;
  27   Link_array<Item> note_spacings_;
  28
  29   Spacings ()
  30   {
  31     staff_spacing_ = 0;
  32   }
  33
  34   bool is_empty () const
  35   {
  36     return !staff_spacing_ && !note_spacings_.size ();
  37   }
  38   void clear ()
  39   {
  40     staff_spacing_ = 0;
  41     note_spacings_.clear ();
  42   }
  43 };
  44
  45 class Separating_line_group_engraver : public Engraver
  46 {
  47 protected:
  48   Item *break_item_;
  49   Item *musical_item_;
  50   Item *last_musical_item_;
  51
  52   Spacings current_spacings_;
  53   Spacings last_spacings_;
  54
  55   Spanner *sep_span_;
  56
  57   DECLARE_ACKNOWLEDGER (item);
  58   void process_music ();
  59   virtual void finalize ();
  60   void stop_translation_timestep ();
  61   void start_translation_timestep ();
  62 public:
  63   TRANSLATOR_DECLARATIONS (Separating_line_group_engraver);
  64 };
  65
  66 Separating_line_group_engraver::Separating_line_group_engraver ()
  67 {
  68   sep_span_ = 0;
  69   break_item_ = 0;
  70   musical_item_ = 0;
  71 }
  72
  73 void
  74 Separating_line_group_engraver::process_music ()
  75 {
  76   if (!sep_span_)
  77     {
  78       sep_span_ = make_spanner ("SeparatingGroupSpanner", SCM_EOL);
  79
  80       sep_span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  81     }
  82 }
  83 void
  84 Separating_line_group_engraver::finalize ()
  85 {
  86   if (!sep_span_)
  87     return;
  88
  89   SCM ccol = get_property ("currentCommandColumn");
  90   Grob *column = unsmob_grob (ccol);
  91
  92   sep_span_->set_bound (RIGHT, unsmob_grob (ccol));
  93   sep_span_ = 0;
  94
  95   for (int i = 0; i < last_spacings_.note_spacings_.size (); i++)
  96     {
  97       Pointer_group_interface::add_grob (last_spacings_.note_spacings_[i],
  98                                          ly_symbol2scm ("right-items"),
  99                                          column);
 100     }
 101
 102   if (last_spacings_.staff_spacing_
 103       && last_spacings_.staff_spacing_->get_column () == column)
 104     last_spacings_.staff_spacing_->suicide ();
 105 }
 106
 107 void
 108 Separating_line_group_engraver::acknowledge_item (Grob_info i)
 109 {
 110   Item *it = dynamic_cast<Item *> (i.grob ());
 111   if (!it)
 112     return;
 113   if (it->get_parent (X_AXIS)
 114       && Axis_group_interface::has_axis (it->get_parent (X_AXIS), X_AXIS))
 115     return;
 116
 117   if (to_boolean (it->get_property ("no-spacing-rods")))
 118     return;
 119
 120   if (Note_spacing::has_interface (it))
 121     {
 122       current_spacings_.note_spacings_.push (it);
 123       return;
 124     }
 125
 126   bool ib = Item::is_breakable (it);
 127   Item *&p_ref_ (ib ? break_item_
 128                  : musical_item_);
 129
 130   if (!p_ref_)
 131     {
 132       p_ref_ = make_item ("SeparationItem", SCM_EOL);
 133
 134       if (ib)
 135         {
 136           p_ref_->set_property ("breakable", SCM_BOOL_T);
 137           context ()->set_property ("breakableSeparationItem", p_ref_->self_scm ());
 138         }
 139
 140       if (to_boolean (get_property ("createSpacing"))
 141           && p_ref_ == break_item_)
 142         {
 143           Item *it = make_item ("StaffSpacing", SCM_EOL);
 144           current_spacings_.staff_spacing_ = it;
 145           Pointer_group_interface::add_grob (it, ly_symbol2scm ("left-items"),
 146                                              break_item_);
 147
 148           if (int i = last_spacings_.note_spacings_.size ())
 149             {
 150               for (; i--;)
 151                 Pointer_group_interface::add_grob (last_spacings_.note_spacings_[i],
 152                                                    ly_symbol2scm ("right-items"),
 153                                                    break_item_);
 154             }
 155           else if (last_spacings_.staff_spacing_)
 156             {
 157               SCM ri = last_spacings_.staff_spacing_->get_object ("right-items");
 158               Grob_array *ga = unsmob_grob_array (ri);
 159               if (!ga)
 160                 {
 161                   SCM ga_scm = Grob_array::make_array ();
 162                   last_spacings_.staff_spacing_->set_object ("right-items", ga_scm);
 163                   ga = unsmob_grob_array (ga_scm);
 164                 }
 165
 166               ga->clear ();
 167               ga->add (break_item_);
 168             }
 169         }
 170     }
 171
 172   if (Accidental_placement::has_interface (it))
 173     Separation_item::add_conditional_item (p_ref_, it);
 174   else
 175     Separation_item::add_item (p_ref_, it);
 176 }
 177
 178 void
 179 Separating_line_group_engraver::start_translation_timestep ()
 180 {
 181   if (break_item_)
 182     {
 183       context ()->unset_property (ly_symbol2scm ("breakableSeparationItem"));
 184       break_item_ = 0;
 185     }
 186 }
 187
 188 void
 189 Separating_line_group_engraver::stop_translation_timestep ()
 190 {
 191   if (break_item_)
 192     Separating_group_spanner::add_spacing_unit (sep_span_, break_item_);
 193
 194   if (Item *sp = current_spacings_.staff_spacing_)
 195     {
 196       /*
 197         TODO: should really look at the left-items of following
 198         note-spacing grobs.
 199       */
 200       if (musical_item_)
 201         Pointer_group_interface::add_grob (sp, ly_symbol2scm ("right-items"),
 202                                            musical_item_);
 203     }
 204
 205   if (!current_spacings_.is_empty ())
 206     last_spacings_ = current_spacings_;
 207
 208   current_spacings_.clear ();
 209
 210   if (musical_item_)
 211     Separating_group_spanner::add_spacing_unit (sep_span_, musical_item_);
 212
 213   musical_item_ = 0;
 214 }
 215
 216 ADD_ACKNOWLEDGER (Separating_line_group_engraver, item);
 217 ADD_TRANSLATOR (Separating_line_group_engraver,
 218                 /* doc */ "Generates objects for computing spacing parameters.",
 219
 220                 /* create */
 221                 "SeparationItem "
 222                 "SeparatingGroupSpanner "
 223                 "StaffSpacing",
 224                 /* accept */ "",
 225                 /* read */ "createSpacing",
 226                 /* write */ "breakableSeparationItem");