[Fontconfig] How to block glyph fallback in a QT application?

Pierre Hanser hanser at club-internet.fr
Thu Jan 9 22:16:43 PST 2014

On 09/01/2014 09:59, Janusz S. Bien wrote:
> Quote/Cytat - Konstantin Ritt <ritt.ks at gmail.com> (Wed 08 Jan 2014
> 01:58:46 AM CET):
> Thank you very much for your explanation.
>> If you're talking about the font fallback implementation:
>> If a font has a gaps in coverage for characters in a given script,
>> then Qt
>> asks FT for a font that best matches the family, style, size, and script
>> (the "most-common" language for that script).
> Is it possible to switch on tracing of the selection process?

fontconfig can be traced with setting FC_DEBUG=xx before running the

xx is a bit field (see fontconfig documentation)

>> In case of ambiguous script,
>> like Inherited, Common, or Han, the language is determined from the
>> environment. If some of those not covered characters still not covered
>> with
>> this font, the loop continues.
>> If that's not what you was asking about, plz provide a context.
> I have to make some additional tests.
> Best regards
> Janusz

More information about the Fontconfig mailing list