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--2005 Han-Wen Nienhuys <hanwen@cs.uu.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       && it->get_parent (X_AXIS)
 115       ->has_extent_callback (Axis_group_interface::group_extent_callback_proc, X_AXIS))
 116     return;
 117
 118   if (to_boolean (it->get_property ("no-spacing-rods")))
 119     return;
 120
 121   if (Note_spacing::has_interface (it))
 122     {
 123       current_spacings_.note_spacings_.push (it);
 124       return;
 125     }
 126
 127   bool ib = Item::is_breakable (it);
 128   Item *&p_ref_ (ib ? break_item_
 129                  : musical_item_);
 130
 131   if (!p_ref_)
 132     {
 133       p_ref_ = make_item ("SeparationItem", SCM_EOL);
 134
 135       if (ib)
 136         {
 137           p_ref_->set_property ("breakable", SCM_BOOL_T);
 138           context ()->set_property ("breakableSeparationItem", p_ref_->self_scm ());
 139         }
 140
 141       if (to_boolean (get_property ("createSpacing"))
 142           && p_ref_ == break_item_)
 143         {
 144           Item *it = make_item ("StaffSpacing", SCM_EOL);
 145           current_spacings_.staff_spacing_ = it;
 146           Pointer_group_interface::add_grob (it, ly_symbol2scm ("left-items"),
 147                                              break_item_);
 148
 149           if (int i = last_spacings_.note_spacings_.size ())
 150             {
 151               for (; i--;)
 152                 Pointer_group_interface::add_grob (last_spacings_.note_spacings_[i],
 153                                                    ly_symbol2scm ("right-items"),
 154                                                    break_item_);
 155             }
 156           else if (last_spacings_.staff_spacing_)
 157             {
 158               SCM ri = last_spacings_.staff_spacing_->get_object ("right-items");
 159               Grob_array *ga = unsmob_grob_array (ri);
 160               if (!ga)
 161                 {
 162                   SCM ga_scm = Grob_array::make_array ();
 163                   last_spacings_.staff_spacing_->set_object ("right-items", ga_scm);
 164                   ga = unsmob_grob_array (ga_scm);
 165                 }
 166
 167               ga->clear ();
 168               ga->add (break_item_);
 169             }
 170         }
 171     }
 172
 173   if (Accidental_placement::has_interface (it))
 174     Separation_item::add_conditional_item (p_ref_, it);
 175   else
 176     Separation_item::add_item (p_ref_, it);
 177 }
 178
 179 void
 180 Separating_line_group_engraver::start_translation_timestep ()
 181 {
 182   if (break_item_)
 183     {
 184       context ()->unset_property (ly_symbol2scm ("breakableSeparationItem"));
 185       break_item_ = 0;
 186     }
 187 }
 188
 189 void
 190 Separating_line_group_engraver::stop_translation_timestep ()
 191 {
 192   if (break_item_)
 193     Separating_group_spanner::add_spacing_unit (sep_span_, break_item_);
 194
 195   if (Item *sp = current_spacings_.staff_spacing_)
 196     {
 197       /*
 198         TODO: should really look at the left-items of following
 199         note-spacing grobs.
 200       */
 201       if (musical_item_)
 202         Pointer_group_interface::add_grob (sp, ly_symbol2scm ("right-items"),
 203                                            musical_item_);
 204     }
 205
 206   if (!current_spacings_.is_empty ())
 207     last_spacings_ = current_spacings_;
 208
 209   current_spacings_.clear ();
 210
 211   if (musical_item_)
 212     Separating_group_spanner::add_spacing_unit (sep_span_, musical_item_);
 213
 214   musical_item_ = 0;
 215 }
 216
 217 ADD_ACKNOWLEDGER (Separating_line_group_engraver, item);
 218 ADD_TRANSLATOR (Separating_line_group_engraver,
 219                 /* doc */ "Generates objects for computing spacing parameters.",
 220
 221                 /* create */
 222                 "SeparationItem "
 223                 "SeparatingGroupSpanner "
 224                 "StaffSpacing",
 225                 /* accept */ "",
 226                 /* read */ "createSpacing",
 227                 /* write */ "breakableSeparationItem");