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--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "separating-group-spanner.hh"
  11 #include "separation-item.hh"
  12 #include "paper-column.hh"
  13 #include "paper-def.hh"
  14 #include "engraver.hh"
  15 #include "axis-group-interface.hh"
  16 #include "note-spacing.hh"
  17 #include "group-interface.hh"
  18 #include "accidental-placement.hh"
  19 #include "translator-group.hh"
  20
  21
  22 struct Spacings
  23 {
  24   Item * staff_spacing_;
  25   Link_array<Item> note_spacings_;
  26
  27   Spacings ()
  28   {
  29     staff_spacing_ = 0;
  30   }
  31
  32   bool empty( )const
  33   {
  34     return !staff_spacing_ && !note_spacings_.size ();
  35   }
  36   void clear () {
  37     staff_spacing_ = 0;
  38     note_spacings_.clear();
  39   }
  40 };
  41
  42
  43 class Separating_line_group_engraver : public Engraver
  44 {
  45 protected:
  46   Item * break_item_;
  47   Item * musical_item_;
  48   Item * last_musical_item_;
  49
  50   Spacings current_spacings_;
  51   Spacings last_spacings_;
  52
  53   Spanner * sep_span_;
  54
  55   virtual void acknowledge_grob (Grob_info);
  56   virtual void process_music ();
  57   virtual void finalize ();
  58   virtual void stop_translation_timestep ();
  59   virtual void start_translation_timestep ();
  60 public:
  61   TRANSLATOR_DECLARATIONS(Separating_line_group_engraver);
  62 };
  63
  64 Separating_line_group_engraver::Separating_line_group_engraver ()
  65 {
  66   sep_span_ = 0;
  67   break_item_ = 0;
  68   musical_item_ =0;
  69 }
  70
  71 void
  72 Separating_line_group_engraver::process_music ()
  73 {
  74
  75   if (!sep_span_)
  76     {
  77       sep_span_ = make_spanner ("SeparatingGroupSpanner");
  78
  79       announce_grob(sep_span_, SCM_EOL);
  80       sep_span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  81     }
  82 }
  83 void
  84 Separating_line_group_engraver::finalize ()
  85 {
  86   SCM ccol = get_property ("currentCommandColumn");
  87   Grob *column = unsmob_grob (ccol);
  88
  89   sep_span_->set_bound (RIGHT, unsmob_grob (ccol));
  90   typeset_grob (sep_span_);
  91   sep_span_ =0;
  92
  93   for  (int i= 0 ; i < last_spacings_.note_spacings_.size(); i++)
  94     {
  95       Pointer_group_interface::add_grob (last_spacings_.note_spacings_[i],
  96                                          ly_symbol2scm ("right-items" ),
  97                                          column);
  98     }
  99
 100   if(last_spacings_.staff_spacing_
 101      && last_spacings_.staff_spacing_->get_column () == column)
 102     {
 103       last_spacings_.staff_spacing_->suicide ();
 104     }
 105 }
 106
 107 void
 108 Separating_line_group_engraver::acknowledge_grob (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       && it->get_parent (X_AXIS)
 115       ->has_extent_callback_b(Axis_group_interface::group_extent_callback_proc, X_AXIS))
 116     return;
 117
 118
 119   if (to_boolean (it->get_grob_property ("no-spacing-rods")))
 120     return ;
 121
 122   if (Note_spacing::has_interface (it))
 123     {
 124       current_spacings_.note_spacings_.push (it);
 125       return ;
 126     }
 127
 128   bool ib =Item::breakable_b (it);
 129   Item *&p_ref_ (ib ? break_item_
 130                  : musical_item_);
 131
 132   if (!p_ref_)
 133     {
 134       p_ref_ = make_item ("SeparationItem");
 135
 136       if (ib)
 137         {
 138           p_ref_->set_grob_property ("breakable", SCM_BOOL_T);
 139           daddy_trans_->set_property ("breakableSeparationItem", p_ref_->self_scm ());
 140         }
 141       announce_grob(p_ref_, SCM_EOL);
 142
 143       if (p_ref_ == break_item_)
 144         {
 145           Item *it  = make_item ("StaffSpacing");
 146           current_spacings_.staff_spacing_ = it;
 147           it->set_grob_property ("left-items", gh_cons (break_item_->self_scm (), SCM_EOL));
 148
 149           announce_grob(it, SCM_EOL);
 150
 151           if (int i = last_spacings_.note_spacings_.size ())
 152             {
 153               for (; i--;)
 154                 Pointer_group_interface::add_grob (last_spacings_.note_spacings_[i],
 155                                                    ly_symbol2scm ("right-items"),
 156                                                    break_item_);
 157
 158             }
 159           else if (last_spacings_.staff_spacing_)
 160             {
 161
 162               last_spacings_.staff_spacing_->set_grob_property ("right-items",
 163                                                                 gh_cons (break_item_->self_scm(), SCM_EOL));
 164             }
 165         }
 166     }
 167
 168   if (Accidental_placement::has_interface (it))
 169     Separation_item::add_conditional_item (p_ref_, it);
 170   else
 171     Separation_item::add_item (p_ref_,it);
 172 }
 173
 174 void
 175 Separating_line_group_engraver::start_translation_timestep ()
 176 {
 177   if (break_item_)
 178     daddy_trans_->unset_property (ly_symbol2scm ("breakableSeparationItem"));
 179   break_item_ =0;
 180 }
 181
 182 void
 183 Separating_line_group_engraver::stop_translation_timestep ()
 184 {
 185   if (break_item_)
 186     {
 187       Separating_group_spanner::add_spacing_unit (sep_span_, break_item_);
 188       typeset_grob (break_item_);
 189     }
 190
 191   if (Item * sp = current_spacings_.staff_spacing_)
 192     {
 193       /*
 194         TODO: should really look at the left-items of following
 195         note-spacing grobs.
 196        */
 197       if (musical_item_)
 198         Pointer_group_interface::add_grob (sp, ly_symbol2scm ("right-items"),
 199                                            musical_item_);
 200
 201       typeset_grob (sp);
 202     }
 203
 204
 205   if (!current_spacings_.empty ())
 206     {
 207       last_spacings_ = current_spacings_;
 208     }
 209
 210   current_spacings_.clear ();
 211
 212   if (musical_item_)
 213     {
 214       Separating_group_spanner::add_spacing_unit (sep_span_, musical_item_);
 215       typeset_grob (musical_item_);
 216     }
 217
 218   musical_item_ =0;
 219 }
 220
 221
 222 ENTER_DESCRIPTION(Separating_line_group_engraver,
 223 /* descr */       "Generates objects for computing spacing parameters.",
 224 /* creats*/       "SeparationItem SeparatingGroupSpanner",
 225 /* accepts */     "",
 226 /* acks  */      "item-interface",
 227 /* reads */       "",
 228 /* write */       "breakableSeparationItem");