[Aleph] OpenType-to-TeX and other musings...

[Idris Samawi Hamid]

Dear friends,

Just some thoughts, while Giuseppe wraps up things...

It is my hope that Aleph eventually be integrated into pdfetex, its key  
features activated with a switch. If that can work, then much of the  
problem of full TeX support of OTF features can be reduced to the  
following:
Convert the otf tables to otp files, perhaps even on the fly (a la  
metafont sources).

One of the problems with the initial implementation of otp's by Omega is  
that the transcription-to-font macros were hard-wired. What is needed, for  
a given language, is the abstraction of the transcription-to-language otp  
sets from the language-to-font otp for that language. I did a proof of  
concept for that a while back, with Giuseppe's and Hans' help, so it's  
certainly doable.

A related issue was mentioned recently to me by William Poser (tangent off  
of a Slashdot discussion on Emacs): Omega tends

"to be oriented toward customization for single languages, not easy use  
with whatever mixture of characters you wanted".

I have had problems mapping some of Unicode's direction-switching commands  
to TeX macros, but assuming that is fixable, then the overall problem  
reduces to the following:

A set of transcription-to-language otp's (presumably transcription=unicode  
but need not be restricted to such) can be loaded, maybe even in the  
format file, covering a multiple of languages. Then one loads the  
language-to-font otps as needed, types in a unicode editor, calls tex and,  
presto! all loaded languages are output, with correct bidirectional order.  
There is no need to make explicit bidi commands because the unicode  
symbols for those commands will be translated into TeX macros via otp.  
(Perhaps XeTeX already does something similar?)

With otf unicode fonts, the tables can be converted to otp and  
automatically plugged into our abstraction layer. All the user has to do  
is write a typescript or fd file, and I have hopes that even that can be  
partially automated, with advanced tweaking left to experts.

I have a feeling that the coming year will be a watershed, and I intend to  
work hard to make that happen!

Best
Idris