On 7/10/2025 9:08 AM, Max Chernoff via ntg-context wrote:
Hi Pablo,
(resending since my attachments were too large for the mailing list the
first time)
I did some experiments yesterday, and I was able to produce a file (PDF
and source attached) that validates as PDF/UA-2 with veraPDF and that
Ulrike Fischer and David Carlisle (who work on the LaTeX accessibility)
confirmed was actually accessible.
I started from the "lpdf-tag-imp-testing.lmt" file that you posted on
the mailing list a while back (I've attached my modified version), and I
also had to modify "lpdf-tag.lmt" (also attached). To get the WTPDF
tags, I also had to uncomment the "conformance" lines in both
lpdf-fmt-imp-ua2.lmt and lpdf-fmt.lmt.
thanks for testing
Some notes:
here's the thing: without yoyur changes (like markinfo which I'm was
checking for the version for a reason, i don't add that kind of checks
for fun), the document validates here, so then i thought, well, let's
update verapdf and for sure a document that validated a while ago
doesn't now .. one can wondert how many validated documents there are
around that actually invalidate now ...
- I had to manually tag every paragraph with
\startparagraph/\stopparagraph, which was annoying.
well, that also depends on the concept of paragraph i guess .. one can't
make structure from non-structure
- I had to hardcode mapping all sections to H1 for the validation to
pass; this obviously won't work in real documents. There's code that
purports to handle this at the end of "lpdf-tag-imp-testing.lmt", but
I couldn't get it to work.
but you still have a lot of NonStructs (the way to play safe) and span's
also can be tricky as (last time Mikael and I looked into that there
were quite some restrictions of what could go in there; the sam eis true
for lbl etc)
- "\setupbackend[format=pdf/ua-2]" needs to come before
"\setuptagging[state=start]", otherwise lots of stuff will silently
break.
Indeed, the format influences some later settings (arbitrary order
initializations would complicate the code with no real gain) .. it might
im prove over time but all this tagging is mostly a "when we're in the
mood and has to be done when we are motivated" and it comes for free (so
it's not driven by some paid project that can set priorities) which btw
is true for pretty much most of context anyway.
> - I've heard that it's actually usually better to put the TeX source in
the Alt text for math instead of the current generated prose, because
most people reading math are familiar with TeX anyways.
Well, i never meet people who are familiar with latex input ... or
expect that from us ... do you expect me to generate something latex
math from less verbose context math? And what about all kind of
(educational) stuff inside there. We try to accomodate what users expect
and challenge us to because that's the world we deal with. The latex is
just a different world (to us); little or no overlap.
Also, isn't the persistent messaging (and ranting) that one should not
use context for articles and such, so why bother. And the embeded xml
blob is probably more reliable than any context -> latex math
conversion. When it comes to math I think most context users are in
education so that's what we focus on.
The proze is also our way to deal with making sure the meaning is kept.
You need to keep in mind that when we started with all this there were
no programs that did anything useful with tagging, that the spec was
(and is) not stable, that validation is a moving target etc ... it's all
about adaptation and it's always easy to point out whatever without
looking at the past and reality one has / had to deal with.
A few decades from not all this tagging will probably be seen as kind of
rediculous anyway.
- The file validates successfully, but there are lots of "Nested MCID"
warnings.
But not invalid, right?
Anyway, I need to check these proposed changes against the (older and
newer) specification,
Again, thanks,
Hans
-----------------------------------------------------------------
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl /
https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive : https://github.com/contextgarden/context
wiki : https://wiki.contextgarden.net
___________________________________________________________________________________
