(struct font_driver): New member get_variation_glyphs.

1 files changed, 11 insertions, 1 deletions

diff --git a/src/font.h b/src/font.h
index 12781d95384..a33577cc130 100644
--- a/src/font.h
+++ b/src/font.h
@@ -653,8 +653,18 @@ struct font_driver
   /* Optional.
 
      If FONT is usable on frame F, return 0.  Otherwise return -1.
-   */
+     This method is used only for debugging.  If this method is NULL,
+     Emacs assumes that the font is usable on any frame.  */
   int (*check) P_ ((FRAME_PTR F, struct font *font));
+
+  /* Optional.
+
+     Return the number of variation glyphs of character C supported by
+     FONT.  VARIATIONS is an array of 256 elements.  If the variation
+     selector N (1..256) defines a glyph, that glyph code is stored in
+     the (N-1)th element of VARIATIONS.  */
+  int (*get_variation_glyphs) P_ ((struct font *font,
+                                   int c, unsigned variations[256]));
 };