Approximates cross-staff slurs in VerticalAxisGroup vertical-skylines.

lily/script-column.cc

 /*
   This file is part of LilyPond, the GNU music typesetter.
 
   Copyright (C) 1999--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
 
@@ skipping 23 matching lines @@
 void
 Script_column::add_side_positioned (Grob *me, Grob *script)
 {
   SCM p = script->get_property ("script-priority");
   if (!scm_is_number (p))
     return;
 
   Pointer_group_interface::add_grob (me, ly_symbol2scm ("scripts"), script);
 }
 
+int
+pushed_by_slur (Grob *g)
+{
+  return g->get_property ("avoid-slur") == ly_symbol2scm ("outside")
+         || g->get_property ("avoid-slur") == ly_symbol2scm ("around");
+}
+
 LY_DEFINE (ly_grob_script_priority_less, "ly:grob-script-priority-less",
            2, 0, 0, (SCM a, SCM b),
            "Compare two grobs by script priority.  For internal use.")
 {
   Grob *i1 = unsmob_grob (a);
   Grob *i2 = unsmob_grob (b);
+
+  /*
+   * avoid-staff of slur trumps script priority. If one grob is

[Keith, 2012/09/22 18:06:47]

'avoid-slur supersedes 'script-priority

+   * supposed to be printed outside a slur and another grob inside,
+   * we place the inside grob below the outside even if the inside
+   * grob has a higher script-priority.
+   */
+  if (unsmob_grob (i1->get_object ("slur"))
+      && unsmob_grob (i2->get_object ("slur")))
+    {
+      int push1 = pushed_by_slur (i1);
+      int push2 = pushed_by_slur (i2);
+      if (push1 != push2)
+        return push1 < push2 ? SCM_BOOL_T : SCM_BOOL_F;
+    }
 
   SCM p1 = i1->get_property ("script-priority");
   SCM p2 = i2->get_property ("script-priority");
 
   return scm_to_int (p1) < scm_to_int (p2) ? SCM_BOOL_T : SCM_BOOL_F;
 }
 
 MAKE_SCHEME_CALLBACK (Script_column, row_before_line_breaking, 1);
 SCM
 Script_column::row_before_line_breaking (SCM smob)
@@ skipping 113 matching lines @@
     }
 }
 
 ADD_INTERFACE (Script_column,
                "An interface that sorts scripts according to their"
                " @code{script-priority} and @code{outside-staff-priority}.",
 
                /* properties */
                ""
               );