- From: John M Slatin <john_slatin@austin.utexas.edu>
- Date: Fri, 14 May 2004 10:34:50 -0500
- To: "Gregg Vanderheiden" <gv@trace.wisc.edu>, <w3c-wai-gl@w3.org>
I think we could add an SVG example without implying that all graphics have to be SVG to conform-- though we might have to say that out loud:-) I was looking for a way to make it clear that it's possible for graphics to have explicit structure. It may be possible for someone who knows SVG bettert to make that point *without* explicitly referencing SVG, and it could be possible to do the same thing for mathematical expressions too. Flash and PDF might be major problems in this regard: Bob Regan has said many times that one of the key *strengths* of Flash, from Macromedia's standpoint, is that it doesn't have structure in the way HTML and other markup languages do; and the strength of PDF is that it basically strips out information about structure in order to preserve the visual presentation as pure presentation. Tagged PDF restores information about document structure, but it's not "natural" to PDF (Loretta, please correct me if I'm wrong about that-- is all PDF now Tagged PDF?). John "Good design is accessible design." Please note our new name and URL! John Slatin, Ph.D. Director, Accessibility Institute University of Texas at Austin FAC 248C 1 University Station G9600 Austin, TX 78712 ph 512-495-4288, f 512-495-4524 email jslatin@mail.utexas.edu web http://www.utexas.edu/research/accessibility/ -----Original Message----- From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Gregg Vanderheiden Sent: Friday, May 14, 2004 10:26 am To: w3c-wai-gl@w3.org Subject: RE: Issue 556 and 669 (and 506 definition of structure) I like this It is more theoretical than older definitions -- but that is good. It gets at the essence of structure rather than its implementation in HTML. I think some HTML examples mixed with the MathML etc would be good. Be careful though. I was just going to suggest we add the SVG example - but that might imply that all graphics had to be SVG in order for content to conform.. hmmmmm Gregg -- ------------------------------ Gregg C Vanderheiden Ph.D. Professor - Ind. Engr. & BioMed Engr. Director - Trace R & D Center University of Wisconsin-Madison -----Original Message----- From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of John M Slatin Sent: Friday, May 14, 2004 8:52 AM To: caldwell@trace.wisc.edu; w3c-wai-gl@w3.org; tcroucher@netalleynetworks.com Subject: RE: Issue 556 and 669 (and 506 definition of structure) This thread is closely related to the thread about #506, in which David and Gregg discuss a revised definition of structure that was put forward by David. Earlier this week, in a message about the 506 thread [1], I wrote that I was concerned that we were defining structure in a way that's too HTML-specific (and too text-specific as well, though I didn't actually say that). I'll paste my proposed definition in here for ease of reference; the full message at [1] includes the exchange between David and Gregg as well as a dictionary definition of structure that was the starting point for mine. <proposed> structure Structure refers to the set of elements and relationships that make up a Web resource. Elements may contain text, graphics, mathematical equations, etc. Some elements may contain other elements, and may also define relationships between two or more elements. We User agents, including Web browsers and some assistive technologies, make the structure of Web resources evident to the user. Some relationships are hierarchical. For example, an HTML document may contain multiple sections. Each section begins with an HTML heading element (<h1>...<h6>) that contains the title of the section or sub-section. The heading element may also show the logical relationship of one section or sub-section to the sections and sub-sections before and after it. In MathML, certain elements are used to show the syntactic structure of mathematical notation-for example, to make it clear that calculations have to be performed in a specific order. In SVG, certain elements (such as the <g> element) are used to define groups of related graphical objects and to provide information about the document's structure. Some relationships are non-hierarchical. For example, non-hierarchical relationships may be created by links between one part of the document and another part, or between the document and another resource. </proposed> I do *not* think this definition is ready for primte-time. I'm not at all certain that it accurately conveys the ideas of structure embodied in SVG and MathML, for example. I put it out here in hopes that we can try to come up with a definition that's broad enough to encompass the broad range of technologies we're concerned with. [1] http://lists.w3.org/Archives/Public/w3c-wai-gl/2004AprJun/0375.html#star t John "Good design is accessible design." Please note our new name and URL! John Slatin, Ph.D. Director, Accessibility Institute University of Texas at Austin FAC 248C 1 University Station G9600 Austin, TX 78712 ph 512-495-4288, f 512-495-4524 email jslatin@mail.utexas.edu web http://www.utexas.edu/research/accessibility/ -----Original Message----- From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Ben Caldwell Sent: Thursday, May 13, 2004 5:08 pm To: w3c-wai-gl@w3.org; tcroucher@netalleynetworks.com Subject: RE: Issue 556 and 669 Finishing some thoughts from the call today... I like the proposal to move emphasis into a separate criterion. Questions: > 1. "Structures and relationships of the content can be derived > programmatically (for example, through a markup or data model)" Tom, are you proposing that we remove the references to hierarchical and non-hierarchical relationships? I think the specific mention of paragraphs, lists, headings, tables, etc. is important to understanding this guideline and helpful to those who come to the guidelines searching for answers to questions like "how do I make tables accessible". > 2. "Differentiation of content to imply additional meaning or stress, > such as the types of emphasis commonly denoted by bold or italics, can > be derived programmatically." Is there a better word than "stress"? Perhaps "... imply additional meaning, emphasis or distinction, such as ..." With regard to the questions raised about whether these criteria imply that the archives of this list would not be accessible, it may be that this is answered through questions about scoping and whether technologies have been used according to specification (guideline 4.1). For scoping, one could claim that the W3C list archives interface meets WCAG 2.0 level one, but that the scope of the claim does not include the content that it receives/processes from external sources (i.e. plain text emails). For the according to spec. question, there is no spec that I know of by which one might mark up structure using plain text. So, plain text content (like the emails submitted to the W3C archives or the comments we've been collecting via form submissions in WCAG Bugzilla) would be excepted. However, in the case of content written in (X)HTML, not using a header tag to mark a header would fail the requirements of 4.1. -Ben
Received on Friday, 14 May 2004 11:35:11 UTC