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

From: Loretta Guarino Reid <lorettaguarino@google.com>
Date: Sat, 3 Nov 2007 20:58:49 -0700
Message-ID: <824e742c0711032058n6682c59euc478e80a0151e081@mail.gmail.com>
To: "Alastair Campbell" <ac@alastairc.ac>
Cc: public-comments-WCAG20@w3.org

Dear Alastair Campbell,

Thank you for your comments on the 17 May 2007 Public Working Draft of
the Web Content Accessibility Guidelines 2.0 (WCAG 2.0
http://www.w3.org/TR/2007/WD-WCAG20-20070517/). The WCAG Working Group
has reviewed all comments received on the May draft, and will be
publishing an updated Public Working Draft shortly. Before we do that,
we would like to know whether we have understood your comments
correctly, and also whether you are satisfied with our resolutions.

Please review our resolutions for the following comments, and reply to
us by 19 November 2007 at public-comments-wcag20@w3.org to say whether
you are satisfied. Note that this list is publicly archived. Note also
that we are not asking for new issues, nor for an updated review of
the entire document at this time.

Please see below for the text of comments that you submitted and our
resolutions to your comments. Each comment includes a link to the
archived copy of your original comment on
http://lists.w3.org/Archives/Public/public-comments-wcag20/, and may
also include links to the relevant changes in the WCAG 2.0 Editor's
Draft of May-October 2007 at

Thank you for your time reviewing and sending comments. Though we
cannot always do exactly what each commenter requests, all of the
comments are valuable to the development of WCAG 2.0.


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: LC-1437 - font scaling
Source: http://lists.w3.org/Archives/Public/public-comments-wcag20/2007Jun/0070.html
(Issue ID: 1990)
Original Comment:

Source: http://www.w3.org/mid/44BEB85A.80707@alastairc.ac
(Issue ID: LC-1437)

1.5 (missing)

I cannot find anything on relative sizing of fonts or layout, at all.
(Also noted in other comments.) I believe these are important aspects
for accessible computers in general as well as the Internet, for
anyone with a mild to moderate visual impairment.

   * The most common user agent Internet Explorer (installed on many
corporate networks) does not allow the resizing of pixel sized fonts.
Nor does the version 7(b3) update. (It does include 'zoom', but this
causes horizontal scrolling on any currently accessible site).
   * Proper 'zooming' is not generally available yet (although some
are working on it.)
   * Fixed width/height layouts suffer from a similar problem, partly
because they often do not react well to increases in font size. There
are some basic layout guidelines for HTML/CSS websites.
   * It is applicable to all screen technologies. For example, Flash
scales well, but is often trapped in a fixed size window. Acrobat has
re-flow & scaling. Other new technologies should be required to scale

Relative fonts or layout may be covered in the techniques (although
not when I last searched), but I believe it should be part of the
normative document (level 2 success criteria).

Proposed Change:

Include a revised version of WCAG 1.0's checkpoint 3.4, example
included below. The font aspects could be added to 1.3, but it does
not seem a natural fit.

Guideline 1.5 Use scalable fonts and layout
Level 1 Success Criteria for Guideline 1.5

(No level 1 success criteria for this guideline.)
Level 2 Success Criteria for Guideline 1.5

1.5.1 text sizing should be specified in a unit that is user
re-sizable. The interface should be perceivable and operable with text
increased to a 200% size.

1.5.2 the layout of the page should allow for a variety of screen
resolutions and sizes by using relative units for the primary layout
areas, such as overall layout, and content area.

Somewhat short, rough and ready, but I can expand on this if the
concept is agreeable. This article on basic layout guidelines
(http://alastairc.ac/2006/05/accessible-layouts/) could provide
inspiration for the CSS techniques.

Response from Working Group:

Although resizing is primarily a user agent function, we have added
new success criteria to address the author's responsibility for
supporting text resizing:

SC 1.4.4 (Level AA): Visually rendered text can be resized without
assistive technology up to 200 percent and down to 50 percent without
loss of content or functionality.

SC 1.4.7 (Level AAA): Visually rendered text can be resized without
assistive technology up to 200 percent and down to 50 percent without
loss of content or functionality and in a way that does not require
the user to scroll horizontally.

Response from Alastair:

My initial response to the decision is here:

Which can be summarised as:
"Ok, that seems reasonable for the issue of font-scaling, but I'm not
sure it's practical to put all the layout scaling issues into the
corner of the user-agent."

The main issue I see when you do scale fonts is fixed (pixel) height
areas that then cause overlapping text. This is an example of a
navigation with increased font sizes in Firefox and zoomed in Opera:

Sometimes narrow fixed widths can be an issue, but it's less common
for it to create an issue.

Response from Working Group:

Content fails both 1.4.4. and 1.4.7 if the letters overlap when
increased using zoom and font resizing (with wrap) respectively (F70).
The different sufficient techniques for SC 1.4.4 rely on the user
agent to different degrees to address layout scaling issues. See

G142 (Using a technology that has commonly-available user agents that
support zoom) relies on the user agent completely. WCAG 2.0 uses
"zoom" to mean scaling all the content, not just the text. So zooming
should not change the layout at all. There are only a few versions of
user agents that currently support zoom, so authors must know their
target environment well to rely on this technique at this time.

The second sufficient technique addresses the author's responsibility
when the user agent provides functionality to change the text size,
but changing text size changes the layout of the Web page. This
technique places requirements both on the measurements used for the
fonts and the measurements used for the containers. A Web page that
uses these techniques should not have overlapping text when the text
size is changed within the 50% to 200% scale. If the letters overlap
when increased using zoom or font resizing (with wrap) respectively,
the content fails both SC 1.4.4. and 1.4.7.

We would welcome help in improving the existing techniques or writing
additional techniques to advise authors on the best ways to address
these layout scaling issues.
Received on Sunday, 4 November 2007 03:59:00 UTC

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