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Re: Z-Order and Tag Order Need to Match?

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From: L Snider
Date: May 28, 2020 8:33AM

Hi Duff,

Yes, it is complex. However, what I would say is that in Word, we don't
need to deal with layers...So what I am saying is why is PDF different? Now
is Word perfect? Nope...but why are we having to spend endless hours trying
to fix PDFs? This is my question, and I am sorry if I went off the original
answer into the weeds, but how many years we will have the same discussion
about PDFs? I wish EPUB had awesome readers, it would change the ballgame
slowly and surely (I know, another story for another thread!).

Cheers

Lisa

On Thu, May 28, 2020 at 9:56 AM Duff Johnson < <EMAIL REMOVED> > wrote:

> Hi Lisa,
>
> There are no "multiple layers" in the PDF in this sense of the term. There
> is simply... content and tags.
> Content is text, graphics, form fields, annotations, etc.
> Tags are semantic structures (H2, P, Table, etc). These are applied to
> content and are used to describe "info and relationships' as per WCAG SC
> 1.3.1. Tags are the only means of providing these structures in PDF.
> Otherwise I fully agree with you, and am very encouraged to hear that you
> are working to convince other software developers to improve their support
> for Tagged PDF.
>
> Duff.
>
> > On May 28, 2020, at 07:53, L Snider < <EMAIL REMOVED> > wrote:
> >
> > Hi Duff,
> >
> > Unfortunately I know all about these layers, but there is still no
> reason.
> > There is no reason to have multiple layers, what you see should be what
> you
> > get...whether you print, tag or whatever...This is partially why, in my
> > personal opinion, PDFs are still inaccessible. 90% of the ones I have
> seen
> > since 2000 are a problem in some way, and most in major ways. Plus tags
> are
> > just one aspect of PDFs, people will all sorts of disabilities use PDFs
> as
> > you know well.
> >
> > I gave up on Adobe, they moved forward for a long, long time and the last
> > 10 years they moved backward. Not in InDesign, InDesign is amazing and
> > kudos to whoever worked on the accessibility aspect of it, now if they
> > could move back those people to PDF we might get back to where PDF
> > was...Microsoft has been kicking butt in terms of accessibility the last
> 5
> > years, so maybe one day Adobe will follow suit.
> >
> > I am now trying to find other PDF creation programs and convince them to
> do
> > better, may have a shot!
> >
> > Cheers
> >
> > Lisa
> >
> > On Wed, May 27, 2020 at 7:48 PM Duff Johnson < <EMAIL REMOVED> >
> wrote:
> >
> >> Hi Lisa,
> >>
> >> Content order and logical reading order are "separate" in PDF because
> the
> >> technology is obliged to represent content for different purposes.
> >> Rendering (e.g., printing) is a different purpose than accessibility,
> for
> >> example, and often requires ordering of content for processing purposes
> >> that differs from logical reading order. PDF was originally designed for
> >> maximum fidelity in print. Accessibility considerations were only
> addressed
> >> in 2000 with the addition of the Tagged PDF feature to the format.
> >>
> >> In 2020 the difficulty is not in the format but in the software.
> >> Unfortunately it remains the case that...
> >> PDF viewer developers don't do a great job of supporting tagged PDF in
> >> many cases. This is simply a business decision.
> >> Users continue to use software that doesn't understand tagged PDF
> instead
> >> of seeking out and demanding better.
> >> Authors continue to author content without consideration for semantics
> >> (e.g., use tab stops instead of table structures, etc.)
> >> I'll beat my usual drum once again: if you want better PDF support,
> >> complain to those who make your software. Demand better support for
> Tagged
> >> PDF. In 2020 there's simply no excuse.
> >>
> >> Duff.
> >>
> >>> On May 27, 2020, at 18:30, Paul Rayius < <EMAIL REMOVED> > wrote:
> >>>
> >>> As per ISO 32000, one of the intents of PDF is that the "accessible
> >> layer" and the visual layer are independent of each other.
> >>>
> >>> Paul Rayius
> >>> Director of Training
> >>> CommonLook
> >>>
> >>> -----Original Message-----
> >>> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of
> >> Ilana Gordon
> >>> Sent: Wednesday, May 27, 2020 5:19 PM
> >>> To: WebAIM Discussion List < <EMAIL REMOVED> >
> >>> Subject: Re: [WebAIM] Z-Order and Tag Order Need to Match?
> >>>
> >>> Agree so completely!
> >>>
> >>> Ilana
> >>>
> >>> On Wed, May 27, 2020 at 5:11 PM L Snider < <EMAIL REMOVED> > wrote:
> >>>
> >>>> What I have been wondering since Acrobat came out with the Z-Order and
> >>>> Tags in the dark ages, why the heck are they still separate in 2020?
> >>>> Can someone enlighten me on why PDFs have to have so many layers, and
> >>>> why they can't be converted to one layer...so we just remediate one
> >>>> layer? I am getting increasingly frustrated with tech from the
> 2000s...
> >>>>
> >>>> Cheers
> >>>>
> >>>> Lisa
> >>>>
> >>>> On Wed, May 27, 2020 at 3:36 PM Paul Rayius < <EMAIL REMOVED> >
> >>>> wrote:
> >>>>
> >>>>> Hi Ilana,
> >>>>> There's often a lot of question/ debate about this. When it comes
> >>>>> to PDF standards (both ISO 32000 and PDF/UA, as well as WCAG 2.0 and
> >>>>> 2.1)
> >>>> they're
> >>>>> all quite clear that the reading order in a PDF shall be determined
> >>>>> by
> >>>> the
> >>>>> order of the tags. (To be more clear, WCAG doesn't specify the
> >>>>> reading order "rules" for PDF but does provide some guidance in the
> >>>>> WCAG
> >>>>> Techniques.)
> >>>>>
> >>>>> The confusion comes into play because some assistive technologies
> >>>>> don't actually follow the standards and so they'll read content from
> >>>>> "other areas" in a PDF - for example from the Content and or
> >>>>> "Z-Order" pane in Acrobat. (The "Z-Order" pane is the one labeled
> >>>>> "Order" but many people call it the "Z-Order" because of the "Z" in
> >>>>> the icon.)
> >>>>>
> >>>>> The problem, however, is that as accessible document creators and/or
> >>>>> remediators, we can't possibly be called on to remediate according
> >>>>> to
> >>>> how a
> >>>>> particular processor or AT will handle a PDF. In fact, to that
> >>>>> point,
> >>>> one
> >>>>> of the great things about WCAG is that it's intended for
> >>>>> accessibility while being technology independent. Personally, I
> >>>>> think it's time for
> >>>> PDF
> >>>>> processors and AT developers to be held accountable and that their
> >>>> products
> >>>>> should adhere to the standards that are not only available but also
> >>>>> achievable. But, that's my soapbox.
> >>>>>
> >>>>> I hope this helps to clarify, though, that the reading order in a
> >>>>> PDF is to be determined by the order of the Tags and not the
> "Z-Order."
> >>>>>
> >>>>> Best,
> >>>>> Paul
> >>>>>
> >>>>> Paul Rayius
> >>>>> Director of Training
> >>>>> CommonLook
> >>>>>
> >>>>> -----Original Message-----
> >>>>> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf
> >>>>> Of Ilana Gordon
> >>>>> Sent: Wednesday, May 27, 2020 12:56 PM
> >>>>> To: WebAIM Discussion List < <EMAIL REMOVED> >
> >>>>> Subject: Re: [WebAIM] Z-Order and Tag Order Need to Match?
> >>>>>
> >>>>> I wish they had a checklist. They are a moving target and keep
> >>>>> asking for things that seem over the top and in additional to the HHS
> >> checklist.
> >>>>>
> >>>>> Ilana
> >>>>>
> >>>>> On Wed, May 27, 2020 at 12:46 PM Ryan E. Benson
> >>>>> < <EMAIL REMOVED> >
> >>>>> wrote:
> >>>>>
> >>>>>> Are you talking to the agency 508 Coordinator directly, or
> >>>>>> somebody
> >>>> else?
> >>>>>> Does the agency have a checklist?
> >>>>>>
> >>>>>> --
> >>>>>> Ryan E. Benson
> >>>>>>
> >>>>>>
> >>>>>> On Wed, May 27, 2020 at 12:23 PM Ilana Gordon
> >>>>>> < <EMAIL REMOVED> >
> >>>>>> wrote:
> >>>>>>
> >>>>>>> I should clarify that this is specifically for PDFs. And some
> >>>>>>> government employee says it's a requirements.
> >>>>>>>
> >>>>>>> Ilana
> >>>>>>>
> >>>>>>> On Wed, May 27, 2020 at 12:17 PM Steve Green <
> >>>>>>> <EMAIL REMOVED> >
> >>>>>>> wrote:
> >>>>>>>
> >>>>>>>> Who is saying it's absolutely necessary? I can see how it
> >>>>>>>> might cause accessibility issues when the layout of pages
> >>>>>>>> change as they are
> >>>>>> zoomed,
> >>>>>>>> but it's by no means inevitable.
> >>>>>>>>
> >>>>>>>> That said, I tend to regard the presence of "z-index"
> >>>>>>>> attributes as a warning that there might be other nastiness
> >>>>>>>> because it suggests the
> >>>>>>> design
> >>>>>>>> is fundamentally flawed. It's the same as when you see
> >>>>>>>> positive
> >>>>>>> "tabindex"
> >>>>>>>> attributes.
> >>>>>>>>
> >>>>>>>> Steve Green
> >>>>>>>> Managing Director
> >>>>>>>> Test Partners Ltd
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> -----Original Message-----
> >>>>>>>> From: WebAIM-Forum < <EMAIL REMOVED> > On
> >>>>>>>> Behalf Of Ilana Gordon
> >>>>>>>> Sent: 27 May 2020 16:58
> >>>>>>>> To: WebAIM Discussion List < <EMAIL REMOVED> >
> >>>>>>>> Subject: [WebAIM] Z-Order and Tag Order Need to Match?
> >>>>>>>>
> >>>>>>>> Can the group weigh in on the latest techniques and efficacy
> >>>>>>>> regarding Z-Order and Tag Order having to match and why this
> >>>>>>>> would be absolutely necessary for Accessibility?
> >>>>>>>>
> >>>>>>>> I'm having many discussions with government 508 officers going
> >>>>>>>> around
> >>>>>> in
> >>>>>>>> circles regarding this issue.
> >>>>>>>>
> >>>>>>>> Any info is appreciated.
> >>>>>>>> Ilana
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>> Ilana Gordon
> >>>>>>>> CEO
> >>>>>>>> Word Wizards, Inc
> >>>>>>>> 8609 2nd Avenue, Unit 406-B
> >>>>>>>> Silver Spring, MD 20910
> >>>>>>>> *v.*301-986-0808 *fax.*301-986-0809
> >>>>>>>> *Direct: 240-380-2639*
> >>>>>>>> www.wordwizardsinc.com
> >>>>>>>> > >>>>>>>> > >>>>>>>> List
> >>>>>> archives
> >>>>>>>> at http://webaim.org/discussion/archives
> >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>> --
> >>>>>>> Ilana Gordon
> >>>>>>> CEO
> >>>>>>> Word Wizards, Inc
> >>>>>>> 8609 2nd Avenue, Unit 406-B
> >>>>>>> Silver Spring, MD 20910
> >>>>>>> *v.*301-986-0808 *fax.*301-986-0809
> >>>>>>> *Direct: 240-380-2639*
> >>>>>>> www.wordwizardsinc.com
> >>>>>>> > >>>>>>> > >>>>>>> archives at http://webaim.org/discussion/archives
> >>>>>>> > >>>>>>>
> >>>>>> > >>>>>> > >>>>>> archives at http://webaim.org/discussion/archives
> >>>>>> > >>>>>>
> >>>>>
> >>>>>
> >>>>> --
> >>>>> Ilana Gordon
> >>>>> CEO
> >>>>> Word Wizards, Inc
> >>>>> 8609 2nd Avenue, Unit 406-B
> >>>>> Silver Spring, MD 20910
> >>>>> *v.*301-986-0808 *fax.*301-986-0809
> >>>>> *Direct: 240-380-2639*
> >>>>> www.wordwizardsinc.com
> >>>>> > >>>>> > >>>>> archives at http://webaim.org/discussion/archives
> >>>>> > >>>>> > >>>>> > >>>>> archives at http://webaim.org/discussion/archives
> >>>>> > >>>>>
> >>>> > >>>> > >>>> archives at http://webaim.org/discussion/archives
> >>>> > >>>>
> >>>
> >>>
> >>> --
> >>> Ilana Gordon
> >>> CEO
> >>> Word Wizards, Inc
> >>> 8609 2nd Avenue, Unit 406-B
> >>> Silver Spring, MD 20910
> >>> *v.*301-986-0808 *fax.*301-986-0809
> >>> *Direct: 240-380-2639*
> >>> www.wordwizardsinc.com
> >>> > >>> > >> archives at http://webaim.org/discussion/archives
> >>> > >>> > >>> > >>> > >>> > >>
> >> > >> > >> > >> > >>
> > > > > > > > >
> > > > >