[lltx] luaotfload update

[Khaled Hosny]

On Mon, Oct 17, 2011 at 06:23:13PM +0200, Ulrike Fischer wrote:
> Am Mon, 17 Oct 2011 10:19:48 +0200 schrieb Khaled Hosny:
> 
>  
> >>> Now the main issue holding the new release is the removed tlig and trep
> >>> feature, I'm still not sure what to do here.
>  
> >> Sorry, I've been away and unable to look into this.
>  
> >> Could we provide a feature-file including the standard TeX ligatures
> >> and use that?
> 
> I sent a small file some days ago which worked fine. It only needs
> some polishing on the script/language side where I don't know the
> best combinition. 
> 
> I personally think a feature file is a good idea. Using lua-code /
> virtual fonts or something like this is imho problematic as the
> context interfaces are not stable enough.    

I think it just needs a (not so) few more `languagesystem` statements
with all possible scripts and language `dflt` (though I need to test
what happens if the font have languages other than default).

> > I think we can have a feature file for that, it would even include all
> > scripts recognised by fontspec so it can work regardless of the chosen
> > script.
> 
> >> Is it possible to use more than a single .fea file to construct the
> >> additional OpenType information? Even if not, it's not the end of the
> >> world, as XeTeX "mapping" files can only be applied single-y and that
> >> hasn't been a big impediment.
> 
> > `featurefile` (should) accept a coma-separated list of files, but this
> > does not work now. I think I found a fix, though.
> 
> I have seen some posting where feature files have been used to
> change the kerning. Actually I think they will be used more with
> luatex as there are text files and so much easier to use. 

My opinion too, (unless if someone wants to implement it by direct node
list processing).

> So I think it is important that you can use more than one feature
> file (or that they can be assembled on-the-fly by fontspec). 

In git now one can pass "featurefile=foo,bar,whatever", but fontspec
FeatureFile option need to be updated to "accumulate" all its
invocations and pass it once to luaotfload so it can be used more than
once. Not something I co do, though.

Regards,
 Khaled