(overline_margin): New variable.

(x_produce_glyphs): Use it.
(syms_of_xdisp): DEFVAR_INT it.

1 files changed, 13 insertions, 3 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 640f7006dd1..4144cf51f6a 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -710,6 +710,10 @@ Lisp_Object Vresize_mini_windows;
 
 struct buffer *displayed_buffer;
 
+/* Space between overline and text. */
+
+EMACS_INT overline_margin;
+
 /* Value returned from text property handlers (see below).  */
 
 enum prop_handled
@@ -20357,7 +20361,7 @@ x_produce_glyphs (it)
           /* If face has an overline, add the height of the overline
              (1 pixel) and a 1 pixel margin to the character height.  */
           if (face->overline_p)
-            it->ascent += 2;
+            it->ascent += overline_margin;
 
           if (it->constrain_row_ascent_descent_p)
             {
@@ -20559,7 +20563,7 @@ x_produce_glyphs (it)
           /* If face has an overline, add the height of the overline
              (1 pixel) and a 1 pixel margin to the character height.  */
           if (face->overline_p)
-            it->ascent += 2;
+            it->ascent += overline_margin;
 
           take_vertical_position_into_account (it);
 
@@ -20834,7 +20838,7 @@ x_produce_glyphs (it)
       /* If face has an overline, add the height of the overline
          (1 pixel) and a 1 pixel margin to the character height.  */
       if (face->overline_p)
-        it->ascent += 2;
+        it->ascent += overline_margin;
 
       take_vertical_position_into_account (it);
 
@@ -24110,6 +24114,12 @@ whose contents depend on various data.  */);
                doc: /* Inhibit try_cursor_movement display optimization.  */);
   inhibit_try_cursor_movement = 0;
 #endif /* GLYPH_DEBUG */
+
+  DEFVAR_INT ("overline-margin", &overline_margin,
+               doc: /* *Space between overline and text, in pixels.
+The default value is 2: the height of the overline (1 pixel) plus 1 pixel
+margin to the caracter height.  */);
+  overline_margin = 2;
 }