Uses the pure-from-neighbor-interface to calculate BarLine extra-spacing-height

[lilypond.git] / lily / bar-line.cc

diff --git a/lily/bar-line.cc b/lily/bar-line.cc
index a56c5f6408bfb684d054958bcf01db4ada238a7b..b9e23a95e4f97ffc9cb8527734289148152527de 100644 (file)
--- a/lily/bar-line.cc
+++ b/lily/bar-line.cc
@@ -34,8 +34,22 @@ Bar_line::calc_bar_extent (SCM smob)
   Interval result;
   Grob *me = unsmob_grob (smob);
   if (Grob *staff = Staff_symbol_referencer::get_staff_symbol (me))
-    result = staff->extent (staff, Y_AXIS);
-
+    {
+      result = staff->extent (staff, Y_AXIS);
+
+      /* Due to rounding problems, bar lines extending to the outermost edges
+         of the staff lines appear wrongly in on-screen display
+         (and, to a lesser extent, in print) - they stick out a pixel.
+         The solution is to extend bar lines only to the middle
+         of the staff line - unless they have different colors,
+         when it would be undesirable.
+      */
+      SCM bar_line_color = me->get_property ("color");
+      SCM staff_color = staff->get_property ("color");
+      Real radius = Staff_symbol_referencer::staff_radius (me);
+      if (bar_line_color == staff_color && radius)
+       result *= (1 - 0.5 * (Staff_symbol_referencer::line_thickness (me) / radius));
+    }
   return ly_interval2scm (result);
 }
 
@@ -453,6 +467,7 @@ ADD_INTERFACE (Bar_line,
                "kern "
                "thin-kern "
                "hair-thickness "
+               "has-span-bar "
                "thick-thickness "
                "glyph "
                "glyph-name "