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Re: SURVEY: Accept requirement for immediate mode graphics a la canvas element?

From: Richard Schwerdtfeger <schwer@us.ibm.com>
Date: Wed, 21 Nov 2007 13:16:11 -0600
To: "Anne van Kesteren" <annevk@opera.com>
Cc: "HTML WG" <public-html@w3.org>, public-html-request@w3.org
Message-ID: <OF8C0BE92A.59601204-ON8625739A.0069376B-8625739A.0069DA7E@us.ibm.com>

Hi Anne,

That is a start. I am not convinced that is workable today since you could
place almost anything on a canvas. and your alternative may depend on the
user. I am looking at providing a vehicle to provide this infrastructure
now in UWA but that is a long way off.

Make sense?


Rich Schwerdtfeger
Distinguished Engineer, SWG Accessibility Architect/Strategist
Chair, IBM Accessibility Architecture Review  Board
blog: http://www.ibm.com/developerworks/blogs/page/schwer

             "Anne van                                                     
             <annevk@opera.com                                          To 
             >                         Richard                             
             Sent by:                  Schwerdtfeger/Austin/IBM@IBMUS      
             public-html-reque                                          cc 
             st@w3.org                 "HTML WG" <public-html@w3.org>      
                                       Re: SURVEY: Accept requirement for  
             11/21/2007 12:04          immediate mode graphics a la canvas 
             PM                        element?                            

Hi Rich,

On Wed, 21 Nov 2007 18:31:53 +0100, Richard Schwerdtfeger
<schwer@us.ibm.com> wrote:
> I object to having <canvas> in HTML 5. There is no vehicle to apply
> accessibility semantics to the markup - unlike SVG.

 From http://www.w3.org/html/wg/html5/#canvas

"When authors use the canvas element, they should also provide content
that, when presented to the user, conveys essentially the same function or

purpose as the bitmap canvas. This content may be placed as content of the

canvas element. The contents of the canvas element, if any, are the
element's fallback content."

And also

"In non-visual media, and in visual media with scripting disabled, the
canvas element's fallback content must be used instead."

So if you could clarify your comment in light of that (and the rest the
section of <canvas> states on this subject, I haven't quoted everything),
that would be much appreciated so we can alleviate the concern.

Kind regards,

Anne van Kesteren

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Received on Wednesday, 21 November 2007 19:17:17 UTC

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