From 4ed1fc73b3949bceb6d6cfb973d6f9e6ab0bb9ba Mon Sep 17 00:00:00 2001
From: Joe Neeman <joeneeman@gmail.com>
Date: Fri, 4 Jul 2008 09:50:48 +0300
Subject: [PATCH] Fix beaming problems with cross-staff beams and slurs.

Mark as cross-staff any grob that is outside or around a
cross-staff slur.
---
 lily/grob-closure.cc | 12 +++++++++---
 lily/include/grob.hh |  1 +
 lily/include/slur.hh |  1 +
 lily/slur.cc         | 22 ++++++++++++++++++++++
 4 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/lily/grob-closure.cc b/lily/grob-closure.cc
index b2d0160ada..124d143793 100644
--- a/lily/grob-closure.cc
+++ b/lily/grob-closure.cc
@@ -67,9 +67,9 @@ add_offset_callback (Grob *g, SCM proc, Axis a)
 
 */
 void
-chain_offset_callback (Grob *g, SCM proc, Axis a)
+chain_callback (Grob *g, SCM proc, SCM sym)
 {
-  SCM data = g->get_property_data (axis_offset_symbol (a));
+  SCM data = g->get_property_data (sym);
 
   if (ly_is_procedure (data))
     data = ly_make_simple_closure (scm_list_1  (data));
@@ -84,9 +84,15 @@ chain_offset_callback (Grob *g, SCM proc, Axis a)
     data = SCM_UNDEFINED;
 
   SCM expr = scm_list_2 (proc, data);
-  g->set_property (axis_offset_symbol (a),
+  g->set_property (sym,
 		   
 		   // twice: one as a wrapper for grob property routines,
 		   // once for the actual delayed binding. 
 		   ly_make_simple_closure (ly_make_simple_closure (expr)));
 }
+
+void
+chain_offset_callback (Grob *g, SCM proc, Axis a)
+{
+  chain_callback (g, proc, axis_offset_symbol (a));
+}
diff --git a/lily/include/grob.hh b/lily/include/grob.hh
index 82591eb7c3..f0191e3e44 100644
--- a/lily/include/grob.hh
+++ b/lily/include/grob.hh
@@ -146,6 +146,7 @@ Interval robust_relative_extent (Grob *, Grob *, Axis);
 /* offset/extent callbacks. */
 void add_offset_callback (Grob *g, SCM proc, Axis a);
 void chain_offset_callback (Grob *g, SCM proc, Axis a);
+void chain_callback (Grob *g, SCM proc, SCM sym);
 SCM axis_offset_symbol (Axis a);
 SCM axis_parent_positioning (Axis a);
 
diff --git a/lily/include/slur.hh b/lily/include/slur.hh
index 3680c73749..5059bdff96 100644
--- a/lily/include/slur.hh
+++ b/lily/include/slur.hh
@@ -27,6 +27,7 @@ public:
   DECLARE_SCHEME_CALLBACK (height, (SCM));
   DECLARE_SCHEME_CALLBACK (outside_slur_callback, (SCM, SCM));
   DECLARE_SCHEME_CALLBACK (pure_outside_slur_callback, (SCM, SCM, SCM, SCM));
+  DECLARE_SCHEME_CALLBACK (outside_slur_cross_staff, (SCM, SCM));
   DECLARE_SCHEME_CALLBACK (calc_cross_staff, (SCM));
   DECLARE_GROB_INTERFACE();
   static Bezier get_curve (Grob *me);
diff --git a/lily/slur.cc b/lily/slur.cc
index 3d47e876fc..faa40725ad 100644
--- a/lily/slur.cc
+++ b/lily/slur.cc
@@ -349,6 +349,7 @@ Slur::auxiliary_acknowledge_extra_object (Grob_info const &info,
       if (slur)
 	{
 	  chain_offset_callback (e, outside_slur_callback_proc, Y_AXIS);
+	  chain_callback (e, outside_slur_cross_staff_proc, ly_symbol2scm("cross-staff"));
 	  e->set_object ("slur", slur->self_scm ());
 	}
     }
@@ -357,6 +358,27 @@ Slur::auxiliary_acknowledge_extra_object (Grob_info const &info,
 		    e->name().c_str ()));
 }
 
+/*
+  A callback that will be chained together with the original cross-staff
+  value of a grob that is placed 'outside or 'around a slur. This just says
+  that any grob becomes cross-staff if it is placed 'outside or 'around a
+  cross-staff slur.
+*/
+MAKE_SCHEME_CALLBACK (Slur, outside_slur_cross_staff, 2)
+SCM
+Slur::outside_slur_cross_staff (SCM smob, SCM previous)
+{
+  if (previous == SCM_BOOL_T)
+    return previous;
+
+  Grob *me = unsmob_grob (smob);
+  Grob *slur = unsmob_grob (me->get_object ("slur"));
+
+  if (!slur)
+    return SCM_BOOL_F;
+  return slur->get_property ("cross-staff");
+}
+
 MAKE_SCHEME_CALLBACK (Slur, calc_cross_staff, 1)
 SCM
 Slur::calc_cross_staff (SCM smob)
-- 
2.39.2