Clarification on Font size calculation using Pango

[arjuna rao chavala <arjunaraoc googlemail com>]

Hi,
I have reported a bug about incorrect title bar sizing when displaying indic-telugu text on title bar.
http://bugzilla.gnome.org/show_bug.cgi?id=571056

The question mark is pointed to pango as the below extract from the above bug shows.
Any feedback will be helpful in addressing this usability feature which must be impacting several languages in Linux.

Regards
Arjun
------- Comment #3 from Thomas Thurman  2009-02-09 16:34 UTC -------
Any Pango experts reading this?  Metacity calculates the height thus:

  PangoFontMetrics *metrics;
  PangoLanguage *lang;

  lang = pango_context_get_language (context);
  metrics = pango_context_get_metrics (context, font_desc, lang);

  retval = PANGO_PIXELS (pango_font_metrics_get_ascent (metrics) +
                         pango_font_metrics_get_descent (metrics));

  pango_font_metrics_unref (metrics);

According to
http://library.gnome.org/devel/pango/unstable/pango-Fonts.html#PangoFontMetrics

the ascent plus the descent *ought* to be the greatest possible height of any
character in the font.  Is this a misinterpretation on Metacity's part, or is
this a problem with the font or with Pango?