- From: Loretta Guarino Reid <lorettaguarino@google.com>
- Date: Sat, 3 Nov 2007 20:58:49 -0700
- 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 http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-20071102/ 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. 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: 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) W2 1.5 (missing) Intent, Description, Examples 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 well. 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: http://alastairc.ac/2007/02/wcag-2-response-on-relative-units/ 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: http://alastairc.ac/images/examples/fixed_height_zoomed.gif 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 http://www.w3.org/TR/UNDERSTANDING-WCAG20/Overview.html#visual-audio-contrast-scale. 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