Re: Font Problems

[Owen Taylor <otaylor redhat com>]

Roozbeh Pournader <roozbeh sharif edu> writes:

> On Tue, 20 Aug 2002, Eric Mader wrote:
> 
> > (Also, while debuggin this, it looks like arabic-xft.c is getting called
> > for *each word* in the Arabic text. I guess that it's finding the space
> > character in another font. This is probably a performance hit...)
> 
> I also noticed this, but I guess this is a feature. Owen?

It's not a feature; it's just hard avoid. The idea I've had in 
mind for a long time is that some characters should be "neutral"
for shaper selection ... and Pango should just use the same shaper
as for the preceding characters.

The issue has been in pango/TODO.xml; I've just filed:

 http://bugzilla.gnome.org/show_bug.cgi?id=91542

To make sure that it is in bugzilla as well.

> > did we perhaps loose some of the bullet-proofing when things got updated
> > to ft2?
> 
> Well, the X Arabic shaper is more powerful (and dirtier) than the OpenType
> one. Just compare 'modules/arabic/arconv.c' and
> 'modules/arabic/arabic-ot.c' (both need a rewrite, of course).

What features in particular do you think are missing from the
OpenType shaper for Arabic?

Most of the complexitiy in the X Arabic shaper is concerned
with being able to use all sorts of different glyph encodings,
which becomes uninteresting when you have OpenType.

Regards,
                                        Owen