Re: [NTG-context] font trickery

Am 15.05.2013 00:51, schrieb Idris Samawi Hamid ادريس سماوي حامد:

Hi Hans,

On Tue, 14 May 2013 12:01:36 -0600, Hans Hagen wrote:

...

I'm on-and-off working on the more technical font manual and in the process also check some old code i've laying around (deciding on what to include and not). I'm also revising the tracer styles.

Which makes me wonder: are there specific additional features that one would like to see in context (mkiv only of course) with respect to font support?

This may be beyond the scope of your current plans, but worth considering: It would be nice to have a mechanism where we can override/add opentype gsub and gpos features. Early on in the history of luatex we once had a mechanism that did this using FontForge's version of Adobe Feature Files. From what I understand, the AFF syntax is finally mature and supports all lookup types:

http://www.adobe.com/devnet/opentype/afdko/topic_feature_file_syntax.html

Or maybe we have our own syntax in lua, goodies etc. Anyway, a way to control/override opentype gsub and gpos behavior would be interesting. Even if a total controller is too ambitious/unwieldy, just being able to do a few basic gsub/gpos tricks may be useful for, e.g., bugs in the font.

Anyway, something to think about.

Best wishes Idris

Hi Idris and Hans, this is a great idea. Is this not available any longer in current luatex? The fontspec (xelatex+lualatex) manual lists this as a luatex only feature (I’ve used it once some time ago). I know a lot of fonts and other problems that could be fixed this way. I’d prefer to stay with the AFF syntax which is well established. Best regards, Georg