Sketchy sketch for a modification to the typesetting backend. (issue4446060)

[mtsolo]

Reviewers: ,

Message:
This patch fixes issue 1632.

Cheers,
MS


Description:
Sketchy sketch for a modification to the typesetting backend.

Please review this at http://codereview.appspot.com/4446060/

Affected files:
  M lily/beam-collision-engraver.cc
  M lily/beam.cc


Index: lily/beam-collision-engraver.cc
diff --git a/lily/beam-collision-engraver.cc  
b/lily/beam-collision-engraver.cc
index  
19e9b82caf2c1d482d1a944a5da588ed89298c0b..cdb4be6270dad054ee13c8a8d55d88e52ef12285  
100644
--- a/lily/beam-collision-engraver.cc
+++ b/lily/beam-collision-engraver.cc
@@ -76,8 +76,6 @@ Beam_collision_engraver::finalize ()
   for (vsize i = 0; i < beams_.size (); i++)
     {
       Grob *beam_grob = beams_[i].grob ();
-      if (Beam::is_cross_staff (beam_grob))
-        continue;

       Context *beam_context = beams_[i].context ();

Index: lily/beam.cc
diff --git a/lily/beam.cc b/lily/beam.cc
index  
1ae30fb5f83745f373671348062be98800f6dbb4..97136c51f578536f8cfb85a54f011f21bd7edc9c  
100644
--- a/lily/beam.cc
+++ b/lily/beam.cc
@@ -1204,7 +1204,16 @@ Beam::shift_region_to_valid (SCM grob, SCM posns)
     {
       if (!covered[i]->is_live())
         continue;
-
+
+      if ((Beam::is_cross_staff (me)
+          && ((Stem::has_interface (covered[i])
+              || Beam::has_interface (covered[i])))))
+        continue;
+
+      if (Beam::has_interface (covered[i]))
+        if (Beam::is_cross_staff (covered[i]))
+          continue;
+
       Box b;
       for (Axis a = X_AXIS; a < NO_AXES; incr (a))
         b[a] = covered[i]->extent (common[a], a);