lily/hara-kiri-group-spanner.cc

   1 /*
   2   hara-kiri-vertical-group-spanner.cc -- implement Hara_kiri_group_spanner
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1998--2000 Jan Nieuwenhuizen <janneke@gnu.org>
   7   Han-Wen Nienhuys <hanwen@cs.uu.nl>
   8 */
   9
  10 #include "axis-group-interface.hh"
  11 #include "spanner.hh"
  12 #include "hara-kiri-group-spanner.hh"
  13 #include "debug.hh"
  14 #include "item.hh"
  15
  16 void
  17 Hara_kiri_group_spanner::set_interface (Score_element*me)
  18 {
  19   me->set_elt_property ("items-worth-living", SCM_EOL);
  20   me->add_offset_callback (force_hara_kiri_callback, Y_AXIS);
  21   me->set_interface (ly_symbol2scm ("hara-kiri-spanner-interface"));
  22 }
  23
  24 bool
  25 Hara_kiri_group_spanner::has_interface (Score_element*me)
  26 {
  27   return me->has_interface (ly_symbol2scm ("hara-kiri-spanner-interface"));
  28 }
  29
  30 void
  31 Hara_kiri_group_spanner::add_interesting_item (Score_element* me,Score_element* n)
  32 {
  33   me->add_dependency (n);
  34   Pointer_group_interface (me, "items-worth-living").add_element (n);
  35 }
  36
  37 void
  38 Hara_kiri_group_spanner::consider_suicide(Score_element*me)
  39 {
  40   SCM worth = me->get_elt_property ("items-worth-living");
  41   if (gh_pair_p (worth))
  42     return ;
  43
  44   Link_array<Score_element> childs = Axis_group_interface::get_children (me);
  45   for (int i = 0; i < childs.size (); i++)
  46     childs[i]->suicide ();
  47
  48
  49   /*
  50     very appropriate name here :-)
  51    */
  52   me->suicide ();
  53 }
  54
  55
  56
  57 /*
  58   We can't rely on offsets and dimensions of elements in a hara-kiri
  59   group. Use a callback to make sure that hara-kiri has been done
  60   before asking for offsets.  */
  61 Real
  62 Hara_kiri_group_spanner::force_hara_kiri_callback (Score_element *elt, Axis a)
  63 {
  64   assert (a == Y_AXIS);
  65   consider_suicide (elt);
  66   return 0.0;
  67 }
  68