- From: Jim Allan <jimallan@tsbvi.edu>
- Date: Thu, 17 May 2012 11:38:08 -0500
- To: WAI-ua <w3c-wai-ua@w3.org>
There is no current wording. The proposal below incorporates the discussion of the thread beginning at http://lists.w3.org/Archives/Public/w3c-wai-ua/2011OctDec/0057.html Proposed: 1.8.z Maintain Point of Regard: By default, when the user changes viewport or content size the point of regard remains at the same relative location within the visible portion of the viewport. {removed the words 'rendering size', not sure what that means. the user can change the viewport size (change the dimensions of the bounding window. the user can change the content size but using the zoom feature, changing the default font size setting, or changing the font size (at least for IE) on a site} Intent of Success Criteria 1.8.z It can be disorienting and confusing when a user changes the viewport size or zooms the content and the current content shifts out of the viewport causing different content on the same page to be displayed in the viewport. Starting with the base assumption that regardless of other content that may have focus, or be selected, the current point of regard is that information that is visible to the user with the bounds of the viewport (user agent content area). There are at least three cases where the user agent may have to take action to keep the point of regard in essentially the same location within the visible portion of the viewport: (a) the viewport is resized; (b) the zoom/scale on the content is changed; or (c) the formatting of some or all of the content changes (e.g. font or text size, causing content to change height and/or rewrap). In these cases the user agent should maintain the same top-left (top-right for RTL) corner UNLESS there is a focussed/selected content INSIDE the pre-zoomed viewport, in which case the focused/selected content remains in the post-zoom viewport. Note: "Content" and "selected" are used because there may be cases where the viewport is zooming into just part of an element (e.g. if I select a few words of text that are part of a <p> and zoom in) (thought of adding this as as the 2nd sentence in the intent. it serves as an alternate example to try to get the point across. "Just as the location in audio does not change when the user increases the volume, the current point of regard should not change when the user changes the size of the window or zooms the content.") Examples of Success Criteria 1.8.z - A user with a distraction disorder (not the best term) is trying to read a text disclaimer (fine print - a smaller font that the default font size) on a page. The disclaimer starts in the top left corner of viewport. The user makes the font size bigger using the zoom feature of the browser. The fonts and images get larger and the top left corner of the content remains the same. The user has a known recognized reference point from which to read the disclaimer. - A user with low vision is trying to read a text disclaimer (fine print a smaller font that the default font size) on a page. The selects (highlights) the disclaimer in the viewport. The user makes the font size bigger using the zoom feature of the browser. The fonts and images get larger. The content shifts as it gets larger to keep the top left portion (at least 5 characters) of the selected content within the viewport The user has a known reference point from which to continue reading the disclaimer. reworded the definition...changed the order of the examples to put graphical window first. added reference to this proper SC point of regard The point of regard is the position in rendered content that the user is presumed to be viewing. The dimensions of the point of regard may vary. For example, it may be a two-dimensional area (e.g. content rendered through a two-dimensional graphical viewport), or a point (e.g. a moment during an audio rendering or a cursor position in a graphical rendering), or a range of text (e.g. focused text). The point of regard is almost always within the viewport, but it may exceed the spatial or temporal dimensions of the viewport (see the definition of rendered content for more information about viewport dimensions). The point of regard may also refer to a particular moment in time for content that changes over time (e.g. an audio-only presentation). User agents may determine the point of regard in a number of ways, including based on viewport position in content, keyboard focus, and selection. The stability of the point of regard is addressed by 1.8.z -- Jim Allan, Accessibility Coordinator & Webmaster Texas School for the Blind and Visually Impaired 1100 W. 45th St., Austin, Texas 78756 voice 512.206.9315 fax: 512.206.9264 http://www.tsbvi.edu/ "We shape our tools and thereafter our tools shape us." McLuhan, 1964
Received on Thursday, 17 May 2012 16:38:41 UTC