+/*
+ separating-group-spanner.cc -- implement Separating_group_spanner
+
+ source file of the GNU LilyPond music typesetter
+
+ (c) 1998--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+*/
+
+#include "separating-group-spanner.hh"
+
+#include "separation-item.hh"
+#include "paper-column.hh"
+#include "output-def.hh"
+#include "dimensions.hh"
+#include "pointer-group-interface.hh"
+#include "moment.hh"
+
+void
+Separating_group_spanner::find_rods (Item *r,
+ vector<Grob*> const &separators,
+ vsize idx,
+ Real padding)
+{
+
+ /*
+ This is an inner loop: look for the first normal (unbroken) Left
+ grob. This looks like an inner loop (ie. quadratic total), but in
+ most cases, the interesting L will just be the first entry of
+ NEXT, making it linear in most of the cases.
+ */
+ for (; idx != VPOS; idx--)
+ {
+ Item *l = dynamic_cast<Item *> (separators[idx]);
+ Item *lb = l->find_prebroken_piece (RIGHT);
+
+ if (lb)
+ {
+ Separation_item::set_distance (Drul_array<Item*> (lb, r), padding);
+ }
+
+ if (Separation_item::set_distance (Drul_array<Item *> (l, r), padding)
+ /*
+ This check is because grace notes are set very tight, and
+ the accidentals of main note may stick out so far to cover
+ a barline preceding the grace note.
+ */
+ && spanned_time_interval (l, r).length ().main_part_ > Rational (0))
+ break;
+
+ /*
+ this grob doesn't cause a constraint. We look further until we
+ find one that does.
+ */
+ }
+}
+
+MAKE_SCHEME_CALLBACK (Separating_group_spanner, set_spacing_rods, 1);
+SCM
+Separating_group_spanner::set_spacing_rods (SCM smob)
+{
+ Grob *me = unsmob_grob (smob);
+
+ /*
+ Ugh: padding is added doubly, also for SeparationItem
+ */
+ Real padding = robust_scm2double (me->get_property ("padding"), 0.1);
+
+ extract_grob_set (me, "elements", elts);
+ for (vsize i = elts.size (); i-- > 1;)
+ {
+ Item *r = dynamic_cast<Item *> (elts[i]);
+ if (!r)
+ continue;
+
+ if (Separation_item::width (r).is_empty ())
+ continue;
+
+ Item *rb
+ = dynamic_cast<Item *> (r->find_prebroken_piece (LEFT));
+
+ find_rods (r, elts, i - 1, padding);
+ if (rb)
+ find_rods (rb, elts, i - 1, padding);
+ }
+
+ return SCM_UNSPECIFIED;
+}
+
+void
+Separating_group_spanner::add_spacing_unit (Grob *me, Item *i)
+{
+ Pointer_group_interface::add_unordered_grob (me, ly_symbol2scm ("elements"), i);
+}
+
+ADD_INTERFACE (Separating_group_spanner,
+ "A spanner that calculates spacing constraints (\"rods\") "
+ "using the @code{separation-item-interface} grobs in @code{elements}.",
+
+ /* properties */
+ "elements "
+ "padding ");