[luatex] luatextra font system

[Ulrike Fischer]

Am Sat, 14 Mar 2009 10:19:24 +0100 schrieb Elie Roux:

>>     The main problem with EU1 encoding, is that it's XeTeX oriented,
>>     so it calls fonts with the XeTeX syntax, which means
>>     \font="[file]" for files in the TDS. I don't really understand why
>>     XeTeX did such an incompatible font syntax, 

Incompatible to who? XeTeX *extended* the standard \font syntax to 
handle the loading of open type fonts but the syntax for all fonts 
that pdftex and raw luatex can handle too is unchanged.


With a font callback luatex can be enable to handle also open types 
fonts. It shouldn't be a problem (as far as I know context/mkiv) 
contains already the necessary code) to write this font back in a 
way that enables luatex to handle also font syntax of XeTeX. 

>> nonsense.

> That's true, it's not really the eu1 encoding itself, but more the 
> eu1*.fd files (for lmroman for example). The problem is we can't have 
> two eu1lmr.fd in the TDS... so they'll need to be adapted, so euenc.dtx 
> need to be adapted...

As long as the lua+latex code needed to load and handle the open 
type fonts is not there it doesn't make much sense to think about 
fd-files. But even if lualatex settles on a extended font syntax for 
open type and/or system fonts incompatible to the XeTeX-syntax the 
eu1*.fd-files are a quite small problem. They are not vital, the 
declaration of the lmodern fonts could be done with fontspec 
commands or luatex use EU2 as generic encoding name. 

And in no case generate a lot of eu1*.fd-files. As you can see if 
you look at xetex/fontspec there are quite unnecessary. Also you 
will never be able to generate all entries for all possible 
combinations of open type features. (fontspec generates the entries 
on the fly and use counters in the family name to distinguish 
different variants.)


If you really want to improve font handling in lualatex you could 
write the necessary code so that until unicode fonts can be used 
with luatex non-ascii input works with TS1,T1....-fonts. 

\documentclass{article}

\usepackage[T1]{fontenc}
\usepackage{textcomp}
\begin{document}

ä, ü, ö, ß, €


\catcode`\ß=\active
\defß{\ss}
\catcode`\€=\active
\def€{\texteuro}

ä, ü, ö, ß, €
\end{document}


-- 
Ulrike Fischer