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--2007 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 "spanner.hh"
  20 #include "grob-array.hh"
  21 #include "pointer-group-interface.hh"
  22
  23 #include "translator.icc"
  24
  25 struct Spacings
  26 {
  27   Item *staff_spacing_;
  28   vector<Item*> note_spacings_;
  29
  30   Spacings ()
  31   {
  32     staff_spacing_ = 0;
  33   }
  34
  35   bool is_empty () const
  36   {
  37     return !staff_spacing_ && !note_spacings_.size ();
  38   }
  39   void clear ()
  40   {
  41     staff_spacing_ = 0;
  42     note_spacings_.clear ();
  43   }
  44 };
  45
  46 class Separating_line_group_engraver : public Engraver
  47 {
  48 protected:
  49   Item *break_item_;
  50   Item *musical_item_;
  51   Item *last_musical_item_;
  52
  53   Spacings current_spacings_;
  54   Spacings last_spacings_;
  55
  56   Spanner *sep_span_;
  57
  58   DECLARE_ACKNOWLEDGER (item);
  59   void process_music ();
  60   virtual void finalize ();
  61   void stop_translation_timestep ();
  62   void start_translation_timestep ();
  63 public:
  64   TRANSLATOR_DECLARATIONS (Separating_line_group_engraver);
  65 };
  66
  67 Separating_line_group_engraver::Separating_line_group_engraver ()
  68 {
  69   sep_span_ = 0;
  70   break_item_ = 0;
  71   musical_item_ = 0;
  72 }
  73
  74 void
  75 Separating_line_group_engraver::process_music ()
  76 {
  77   if (!sep_span_)
  78     {
  79       sep_span_ = make_spanner ("SeparatingGroupSpanner", SCM_EOL);
  80
  81       sep_span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  82     }
  83 }
  84 void
  85 Separating_line_group_engraver::finalize ()
  86 {
  87   if (!sep_span_)
  88     return;
  89
  90   SCM ccol = get_property ("currentCommandColumn");
  91   Grob *column = unsmob_grob (ccol);
  92
  93   sep_span_->set_bound (RIGHT, unsmob_grob (ccol));
  94   sep_span_ = 0;
  95
  96   if (last_spacings_.staff_spacing_
  97       && last_spacings_.staff_spacing_->get_column () == column)
  98     last_spacings_.staff_spacing_->suicide ();
  99 }
 100
 101 void
 102 Separating_line_group_engraver::acknowledge_item (Grob_info i)
 103 {
 104   Item *it = i.item ();
 105   if (it->get_parent (X_AXIS)
 106       && it->get_parent (X_AXIS) == it->get_parent (Y_AXIS)
 107       && Axis_group_interface::has_axis (it->get_parent (X_AXIS), X_AXIS)
 108       && Axis_group_interface::has_axis (it->get_parent (Y_AXIS), Y_AXIS))
 109     return;
 110
 111   if (to_boolean (it->get_property ("no-spacing-rods")))
 112     return;
 113
 114   if (Note_spacing::has_interface (it))
 115     {
 116       current_spacings_.note_spacings_.push_back (it);
 117       return;
 118     }
 119
 120   bool ib = Item::is_non_musical (it);
 121   Item *&p_ref_ (ib ? break_item_
 122                  : musical_item_);
 123
 124   if (!p_ref_)
 125     {
 126       p_ref_ = make_item ("SeparationItem", SCM_EOL);
 127
 128       if (ib)
 129         {
 130           p_ref_->set_property ("non-musical", SCM_BOOL_T);
 131           context ()->set_property ("breakableSeparationItem", p_ref_->self_scm ());
 132         }
 133
 134       if (to_boolean (get_property ("createSpacing"))
 135           && p_ref_ == break_item_)
 136         {
 137           Item *it = make_item ("StaffSpacing", SCM_EOL);
 138           current_spacings_.staff_spacing_ = it;
 139           Pointer_group_interface::add_grob (it, ly_symbol2scm ("left-items"),
 140                                              break_item_);
 141
 142           if (!last_spacings_.note_spacings_.size ()
 143               && last_spacings_.staff_spacing_)
 144             {
 145               SCM ri = last_spacings_.staff_spacing_->get_object ("right-items");
 146               Grob_array *ga = unsmob_grob_array (ri);
 147               if (!ga)
 148                 {
 149                   SCM ga_scm = Grob_array::make_array ();
 150                   last_spacings_.staff_spacing_->set_object ("right-items", ga_scm);
 151                   ga = unsmob_grob_array (ga_scm);
 152                 }
 153
 154               ga->clear ();
 155               ga->add (break_item_);
 156             }
 157         }
 158     }
 159
 160   if (Accidental_placement::has_interface (it))
 161     Separation_item::add_conditional_item (p_ref_, it);
 162   else
 163     Separation_item::add_item (p_ref_, it);
 164 }
 165
 166 void
 167 Separating_line_group_engraver::start_translation_timestep ()
 168 {
 169   if (break_item_)
 170     {
 171       context ()->unset_property (ly_symbol2scm ("breakableSeparationItem"));
 172       break_item_ = 0;
 173     }
 174 }
 175
 176 void
 177 Separating_line_group_engraver::stop_translation_timestep ()
 178 {
 179   if (break_item_)
 180     Separating_group_spanner::add_spacing_unit (sep_span_, break_item_);
 181
 182   if (Item *sp = current_spacings_.staff_spacing_)
 183     {
 184       /*
 185         TODO: should really look at the left-items of following
 186         note-spacing grobs.
 187       */
 188       if (musical_item_)
 189         Pointer_group_interface::add_grob (sp, ly_symbol2scm ("right-items"),
 190                                            musical_item_);
 191     }
 192
 193   if (!current_spacings_.is_empty ())
 194     last_spacings_ = current_spacings_;
 195
 196   current_spacings_.clear ();
 197
 198   if (musical_item_)
 199     Separating_group_spanner::add_spacing_unit (sep_span_, musical_item_);
 200
 201   musical_item_ = 0;
 202 }
 203
 204 ADD_ACKNOWLEDGER (Separating_line_group_engraver, item);
 205 ADD_TRANSLATOR (Separating_line_group_engraver,
 206                 /* doc */ "Generates objects for computing spacing parameters.",
 207
 208                 /* create */
 209                 "SeparationItem "
 210                 "SeparatingGroupSpanner "
 211                 "StaffSpacing",
 212                 /* read */ "createSpacing",
 213                 /* write */ "breakableSeparationItem");