Fix off-by-one error in max_system_count.

[lilypond.git] / lily / grob.cc

diff --git a/lily/grob.cc b/lily/grob.cc
index 495fe2437f97cbddabfb90712d08afbc9c6f3928..fbb4683f4a7f2173c1d9e70b2afe7d86db73cd20 100644 (file)
--- a/lily/grob.cc
+++ b/lily/grob.cc
@@ -288,16 +288,23 @@ Grob::pure_relative_y_coordinate (Grob const *refp, int start, int end)
   Real off = 0;
 
   if (dim_cache_[Y_AXIS].offset_)
-    off = *dim_cache_[Y_AXIS].offset_;
+    {
+      if (to_boolean (get_property ("pure-Y-offset-in-progress")))
+       programming_error ("cyclic chain in pure-Y-offset callbacks");
+
+      off = *dim_cache_[Y_AXIS].offset_;
+    }
   else
     {
       SCM proc = get_property_data ("Y-offset");
 
       dim_cache_[Y_AXIS].offset_ = new Real (0.0);
+      set_property ("pure-Y-offset-in-progress", SCM_BOOL_T);
       off = robust_scm2double (call_pure_function (proc,
                                                   scm_list_1 (self_scm ()),
                                                   start, end),
                               0.0);
+      del_property ("pure-Y-offset-in-progress");
       delete dim_cache_[Y_AXIS].offset_;
       dim_cache_[Y_AXIS].offset_ = 0;
     }
@@ -433,7 +440,8 @@ Grob::pure_height (Grob *refp, int start, int end)
   if (!iv.is_empty () && is_number_pair (min_ext))
     iv.unite (ly_scm2interval (min_ext));
 
-  iv.translate (offset);
+  if (!iv.is_empty ())
+    iv.translate (offset);
   return iv;
 }
 
@@ -625,6 +633,7 @@ ADD_INTERFACE (Grob,
               "outside-staff-horizontal-padding "
               "outside-staff-padding "
               "outside-staff-priority "
+              "pure-Y-offset-in-progress "
               "rotation "
               "springs-and-rods "
               "staff-symbol "