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 "separation-item.hh"
  12 #include "paper-column.hh"
  13 #include "output-def.hh"
  14 #include "axis-group-interface.hh"
  15 #include "note-spacing.hh"
  16 #include "accidental-placement.hh"
  17 #include "context.hh"
  18 #include "spanner.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   vector<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   Spacings current_spacings_;
  49   Spacings last_spacings_;
  50
  51   DECLARE_ACKNOWLEDGER (item);
  52   void stop_translation_timestep ();
  53 public:
  54   TRANSLATOR_DECLARATIONS (Separating_line_group_engraver);
  55 };
  56
  57 Separating_line_group_engraver::Separating_line_group_engraver ()
  58 {
  59 }
  60
  61 void
  62 Separating_line_group_engraver::acknowledge_item (Grob_info i)
  63 {
  64   Item *it = i.item ();
  65
  66   if (Note_spacing::has_interface (it))
  67     {
  68       current_spacings_.note_spacings_.push_back (it);
  69       return;
  70     }
  71
  72   if (Item::is_non_musical (it)
  73       && !current_spacings_.staff_spacing_
  74       && to_boolean (get_property ("createSpacing")))
  75     {
  76       current_spacings_.staff_spacing_ = make_item ("StaffSpacing", SCM_EOL);
  77
  78       if (!last_spacings_.note_spacings_.size ()
  79           && last_spacings_.staff_spacing_)
  80         {
  81           SCM ri = last_spacings_.staff_spacing_->get_object ("right-items");
  82           Grob_array *ga = unsmob_grob_array (ri);
  83           if (!ga)
  84             {
  85               SCM ga_scm = Grob_array::make_array ();
  86               last_spacings_.staff_spacing_->set_object ("right-items", ga_scm);
  87               ga = unsmob_grob_array (ga_scm);
  88             }
  89
  90           ga->clear ();
  91           ga->add (unsmob_grob (get_property ("currentCommandColumn")));
  92         }
  93     }
  94 }
  95
  96 void
  97 Separating_line_group_engraver::stop_translation_timestep ()
  98 {
  99   if (!current_spacings_.is_empty ())
 100     last_spacings_ = current_spacings_;
 101
 102   current_spacings_.clear ();
 103 }
 104
 105 ADD_ACKNOWLEDGER (Separating_line_group_engraver, item);
 106 ADD_TRANSLATOR (Separating_line_group_engraver,
 107                 /* doc */ "Generates objects for computing spacing parameters.",
 108
 109                 /* create */ "StaffSpacing",
 110                 /* read */ "createSpacing",
 111                 /* write */ ""
 112                 );