[Fontconfig] Improving Latin font selection for CJK locales

[Behdad Esfahbod]

(Keith, you forgot Reply All?)

On Tue, 2008-01-29 at 06:56 +1100, Keith Packard wrote:
> On Mon, 2008-01-28 at 13:59 -0500, Behdad Esfahbod wrote:
> 
> > Yes, and with my proposed syntax of having a separate "script" element
> > you can do that.  So you have a pattern of :lang="ja":script="han " for
> > example.
> 
> What standard do we reference for these 'script' tags?

I see three possibilities:

  - Human-readable names defined in Unicode.  That's what Pango uses.

  - ISO-15924.  Problem with this one is that mapping from Unicode names
is not unique.  Some may say that's an advantage though.

  - OpenType script tags.  Not a good idea really.

> And, what standard do we reference for the related sub-orthography?

Not sure.  The main reason I need it is not to refine charset selection,
but to make it easier to match on all languages using a script.
Fontconfig can add that info to its orth files such that it
automatically fills script="arabic" if lang="fa", but that's not
necessary.

That said, I'm not sure about this feature yet as it's not trivial to
make pango pass this info, because pango groups common characters with
non-common characters, so if a run starts with a common characters, we
need to choose a font but we don't have a script yet.

Anyway, main purpose of my mail was the "locale" element which can be
used to solve real problems now.


Thanks,
-- 
behdad
http://behdad.org/

"Those who would give up Essential Liberty to purchase a little
 Temporary Safety, deserve neither Liberty nor Safety."
        -- Benjamin Franklin, 1759