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--2004 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 "warn.hh"
  14 #include "item.hh"
  15
  16
  17 MAKE_SCHEME_CALLBACK (Hara_kiri_group_spanner,y_extent,2);
  18 SCM
  19 Hara_kiri_group_spanner::y_extent (SCM element_smob, SCM scm_axis)
  20 {
  21   Grob *me = unsmob_grob (element_smob);
  22   Axis a = (Axis) gh_scm2int (scm_axis);
  23
  24   assert (a == Y_AXIS);
  25   consider_suicide (me);
  26   return  Axis_group_interface::group_extent_callback (me->self_scm (), scm_axis);
  27 }
  28
  29
  30 void
  31 Hara_kiri_group_spanner::consider_suicide (Grob*me)
  32 {
  33   Spanner*sp = dynamic_cast<Spanner*> (me);
  34   SCM worth = me->get_property ("items-worth-living");
  35   if (gh_pair_p (worth))
  36     return ;
  37
  38   if (!to_boolean (me->get_property ("remove-first"))
  39       && broken_spanner_index (sp) == 0)
  40     {
  41       return ;
  42     }
  43
  44   Link_array<Grob> 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 MAKE_SCHEME_CALLBACK (Hara_kiri_group_spanner,force_hara_kiri_callback,2);
  62 SCM
  63 Hara_kiri_group_spanner::force_hara_kiri_callback (SCM element_smob, SCM axis)
  64 {
  65   Grob *me = unsmob_grob (element_smob);
  66   Axis a = (Axis) gh_scm2int (axis);
  67   assert (a == Y_AXIS);
  68   consider_suicide (me);
  69   return gh_double2scm (0.0);
  70 }
  71
  72
  73 MAKE_SCHEME_CALLBACK (Hara_kiri_group_spanner,force_hara_kiri_in_parent_callback,2);
  74 SCM
  75 Hara_kiri_group_spanner::force_hara_kiri_in_parent_callback (SCM element_smob, SCM axis)
  76 {
  77   Grob *daughter = unsmob_grob (element_smob);
  78   Axis a = (Axis) gh_scm2int (axis);
  79   assert (a == Y_AXIS);
  80   force_hara_kiri_callback (daughter->get_parent (a)->self_scm (), axis);
  81   return gh_double2scm (0.0);
  82 }
  83
  84 void
  85 Hara_kiri_group_spanner::add_element (Grob * me, Grob *e)
  86 {
  87   //  e->add_offset_callback (force_hara_kiri_in_parent_callback, Y_AXIS);
  88   Axis_group_interface::add_element (me, e);
  89 }
  90
  91
  92
  93
  94
  95 void
  96 Hara_kiri_group_spanner::add_interesting_item (Grob* me,Grob* n)
  97 {
  98   me->add_dependency (n);
  99   Pointer_group_interface::add_grob (me, ly_symbol2scm ("items-worth-living"),n);
 100 }
 101
 102
 103 ADD_INTERFACE (Hara_kiri_group_spanner,"hara-kiri-group-interface",
 104                "A group spanner that  keeps track of interesting items.  If it "
 105                "doesn't contain any after linebreaking, then it "
 106                "will remove itself and all its children."
 107                ,
 108                "items-worth-living remove-first");
 109