[XeTeX] OT features

[Khaled Hosny]

On Mon, Feb 14, 2011 at 10:24:14PM +0100, Georg A. Duffner wrote:
> For my font project (see www.georgduffner.at/ebgaramond) i have been
> playing around with some opentype features. It seems, that
> contextual features involving the character "space" don’t work as
> expected.

AFAIK, XeTeX processes each word in isolation, so space never part of
context (also in TeX space is not a character/glyph but a kind of a
property named glue, so it does not get handled by OT layout).

Generally speaking, using space in context is fragile and not guaranteed
to work everywhere.

> I wanted to implement a feature for latin texts that
> replaces "u" at the beginning of a word by a letter that looks like
> "v". The rule looks like this:

'init' feature should be more suitable here, but almost all OT engine
supports it for few selected scripts (Arabic mainly). With 'init' it is
the responsibility of the engine to detect word beginning.

Regards,
 Khaled

-- 
 Khaled Hosny
 Egyptian