[XeTeX] XeTeX maintenance

[Ross Moore]

Hi all,

On 26/04/2015, at 20:51, Joseph Wright <joseph.wright at morningstar2.co.uk> wrote:

> On 26/04/2015 11:47, Philip Taylor wrote:
>> To my mind, XeTeX /is/ the future of TeX.  The days of entering
>> "français" as "fran\c cais" are surely numbered, and it has never been
>> possible to enter "العربية", "ελληνικά" or "עברית" (etc) in an analogous
>> way.  Therefore, is it not time to petition the TUG Board to adopt XeTeX
>> as a formal TUG project, and to allocate adequate funding to ensure not
>> only its continued existence but its continued development, at least
>> until such time as a clearly superior alternative not only emerges but
>> becomes adopted as the /de facto/ replacement for TeX ?
>> 
>> Philip Taylor
> 
> The problem as always is not so much money as people. [Also, you do know
> about LuaTeX, yes? ;-) More seriously, XeTeX isn't a drop-in replacement
> for TeX90/pdfTeX.]

There is an even bigger issue which is going to affect the future of TeX.

http://www.access-board.gov/guidelines-and-standards/communications-and-it/about-the-ict-refresh/proposed-rule

The laws (in the US, but this will propagate) are going to becoming much tougher about requiring Accessibility of electronic documents, both for websites and PDFs.
Basically all PDFs (produced by government agencies for public consumption) *must* satisfy the PDF/UA published standard. That is, they must be Tagged PDF, and satisfy all the extra recommendations for enhancing Accessibility of the document's content and structure.
Being a legal requirement for Government Agencies has a knock-on effect for everyone, so TeX software will need to be enhanced to meet such requirements, else extinction becomes a real possibility.

No standard TeX implementation currently comes close to producing Tagged PDF.
LuaTeX, with it's extra scripting, has the potential to do so.
Extra primitives for pdfTeX go a long way, but require 1000s of extra lines of TeX/LaTeX coding to implement proper structure tagging without placing a burden on authors.
(Those primitives are not yet standard in pdfTeX, but are in a separate development branch.)

It may be possible to continue with a  .tex  —> .dvi —> .pdf  workflow, but I doubt it very much.
Structure tagging requires a completely separate tree-like view of a document’s structure and which must be interleaved with the content within the page-tree structure. Storing everything that will be required into the .dvi  file, on a page-page basis for later processing by a separate program, is unlikely to give a viable solution; at least not without substantial extension of  dvips , dvipdfmx, etc. and Ghostscript itself perhaps.

Direct production of the PDF by a single engine is surely the best approach.


> --
> Joseph Wright


Hope this helps,

    Ross