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Re: Your comments on WCAG 2.0 Public Working Draft of May, 2007

From: Loretta Guarino Reid <lorettaguarino@google.com>
Date: Tue, 11 Dec 2007 15:32:00 -0800
Message-ID: <824e742c0712111532w461a2cf1k47ae7c385023e052@mail.gmail.com>
To: yukie.motomiya.zm@hitachi.com
Cc: public-comments-WCAG20@w3.org

We have removed the clause "and down to 50 percent" from the success criterion.

The kind of functionality loss that often occurs as users increase the
font size is that text overlaps with other content on the page so that
it cannot be read. This may happen because the author has used layout
measurements that do not scale with the text size.

Regards,

Loretta Guarino Reid, WCAG WG Co-Chair
Gregg Vanderheiden, WCAG WG Co-Chair
Michael Cooper, WCAG WG Staff Contact

On behalf of the WCAG Working Group

> >----------------------------------------------------------
> >Comment 1: Grounds for "200%"
> >Source: http://lists.w3.org/Archives/Public/public-comments-wcag20/2007Jun/0283.html
> >(Issue ID: 2112)
> >----------------------------
> >Original Comment:
> >----------------------------
> >
> >We have two questions on 1.4.4 and 1.4.7:
> >
> > Q1. Why "200%" and "50%"?
> >
> > Q2. Why do the authors have to be responsible for "200%"?
> >
> >
> >We couldn't understand the reason why the authors should ensure that
> >the "visually rendered text can be resized without assistive
> >technology up to 200 percent and down to 50 percent". In the section
> >of "Intent of this Success Criterion", it reads "The working group
> >feels that 200% is a reasonable accommodation that can support a wide
> >range of designs and layouts, ...". However there should be more
> >concrete reason why the working group feels "200%" and "50%" are
> >reasonable. Also we'd like to know this percentage can be applied to
> >the characters in any other languages such as CJK languages.
> >
> >
> >Additionally, all the authors have to do is to use relative
> >measurements in order to make text resizable. Do these SC mean that
> >the authors should provide the mechanism with users to resize text up
> >to 200 percent and down to 50 percent? If so, it should be done by the
> >user agents.
> >
> >Proposed Change:
> >- Add the concrete reason why "200%"/"50%" and the sufficient grounds
> >for any other languages than English. Or change these SCs to simply
> >saying "Visually rendered text can be resized by the user agents
> >without assistive technology."
> >
> >- Add the concrete reason why "authors" should be responsible for
> >"200%" and "50%".
> >
> >---------------------------------------------
> >Response from Working Group:
> >---------------------------------------------
> >
> >The working group spent a lot of time discussing such options; in
> >fact, some of our initial proposals looked very much like your
> >suggestion, "Visually rendered text can be resized by the user agents
> >without assistive technology." However, we discovered several
> >problems.
>
> >
> >As text is scaled larger and larger, it becomes impossible to prevent
> >loss of content or functionality. When horizontal text is enlarged
> >beyond a certain level, text wrapping algorithms turn the text into a
> >vertical column of words, possibly clipped if the word itself is too
> >large to fit into the available horizontal space on screen. For
> >vertical text, similar problems occur.
> >
> >Arbitrary resizing also introduces problems with testing. How does an
> >author know when he has satisfied the success criterion, particularly
> >for more sophisticated web pages that may change their layout  based
> >on the text size to produce more readable results. An example would be
> >a page that switches between single and multiple column text so that
> >line widths stay within the ~16 word range recommended for some
> >cognitive, learning, and language disabilities.
> >
> >So we felt that some choice of explicit values was necessary to make
> >these success criteria testable. 200% was chosen after experimenting
> >with various web pages that the working group felt were well designed,
> >to see when scaling started to introduce problems. We also looked at
> >the scaling supported directly by popular browsers. (IE's largest text
> >scaling factor is only about 180%). And we looked at the support
> >provided by screen magnifiers. For older screen magnifiers, 200% was
> >the smallest scale factor that could be chosen. 50% was chosen to
> >provide symmetry in the ranges. The ability to scale in both
> >directions is desirable.
> >
> >We believe that there is a range of visual disabilities that can best
> >be addressed directly and a range where the most effective solutions
> >rely on assistive technology such as screen magnifiers. Other success
> >criteria ensure that assistive technology can access the content
> >successfully. These new success criteria identify the author's
> >responsibility when supporting users where direct access is more
> >effective.
> >
> >Note, by the way, that the success criteria don't require just scaling
> >to 200% and 50%, but to all the values between. Our expectation is
> >that solutions that work across that range will continue to work "as
> >well as possible" beyond those limits.
> >
> >This is explained in the Intent Section of Understanding SC 1.4.4. The
> >Working Group welcomes suggestions for ways to make this information
> >clearer.
>
> >---------------------------------------------
> >My Comment:
> >---------------------------------------------
> I wonder if you have checked that this percentage can be applied to the characters in any other languages such as CJK languages as I mentioned in my original comment.
>
> Thinking about Japanese, I can't imagine in what case loss of content or functionality happens.
> I mean if we make text resizable.
>
> For example, sentences in Japanese don't have "space" in between words and wrapping algorithms merely make the text into a vertical column of words.
> Please check this in our company's web site.
>
> -Hitachi(Japan site)
> http://www.hitachi.co.jp/
>
>
> Also the percentage "50%" is too small for at least Japanese language and if we make the text in 50% we can't recognize what is written because the text(character) sometimes very complicated and can be crashed.
>
>
> So I again propose that
> >- Add the concrete reason why "200%"/"50%" and the sufficient grounds
> >for any other languages than English. Or change these SCs to simply
> >saying "Visually rendered text can be resized by the user agents
> >without assistive technology."
> >
> >- Add the concrete reason why "authors" should be responsible for
> >"200%" and "50%".
Received on Tuesday, 11 December 2007 23:32:13 UTC

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