Ignore global advance width unconditionally

Some (arguably) broken CJK fonts claim to have a fixed advance width,
but they actually use two different widths for half-width and full-width
characters. Even worse, some use proportional width.
This can cause problems under certain circumstances.  A big project
(Cairo) uses a FreeType load flag to ignore the global advance width
for such fonts, so I assume it can be used safely. Let's do it just
like them.

diff --git a/libass/ass_font.c b/libass/ass_font.c
index 7db1f076f7b3988fae04eab4c67372adfb7ccefe..bb2b96a97d74bee5641ed36e4cb7e93bb757edb4 100644 (file)
--- a/libass/ass_font.c
+++ b/libass/ass_font.c
@@ -451,22 +451,22 @@ FT_Glyph ass_font_get_glyph(void *fontconfig_priv, ASS_Font *font,
     }
 #endif
 
+    flags = FT_LOAD_NO_BITMAP | FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH;
     switch (hinting) {
     case ASS_HINTING_NONE:
-        flags = FT_LOAD_NO_HINTING;
+        flags |= FT_LOAD_NO_HINTING;
         break;
     case ASS_HINTING_LIGHT:
-        flags = FT_LOAD_FORCE_AUTOHINT | FT_LOAD_TARGET_LIGHT;
+        flags |= FT_LOAD_FORCE_AUTOHINT | FT_LOAD_TARGET_LIGHT;
         break;
     case ASS_HINTING_NORMAL:
-        flags = FT_LOAD_FORCE_AUTOHINT;
+        flags |= FT_LOAD_FORCE_AUTOHINT;
         break;
     case ASS_HINTING_NATIVE:
-        flags = 0;
         break;
     }
 
-    error = FT_Load_Glyph(face, index, FT_LOAD_NO_BITMAP | flags);
+    error = FT_Load_Glyph(face, index, flags);
     if (error) {
         ass_msg(font->library, MSGL_WARN, "Error loading glyph, index %d",
                 index);