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Re: HTML 5 Canvas Accessibility Call on January 10

From: Richard Schwerdtfeger <schwer@us.ibm.com>
Date: Mon, 10 Jan 2011 13:44:06 -0600
To: Charles Pritchard <chuck@jumis.com>
Cc: Cynthia Shelly <cyns@microsoft.com>, "david.bolter@gmail.com" <david.bolter@gmail.com>, Frank Olivier <Frank.Olivier@microsoft.com>, "janina@rednote.net" <janina@rednote.net>, "oedipus@hicom.net" <oedipus@hicom.net>, "public-canvas-api@w3.org" <public-canvas-api@w3.org>, "public-html-a11y@w3.org" <public-html-a11y@w3.org>, Shawn Warren <swarren@aisquared.com>, Tim Lalor <tlalor@aisquared.com>
Message-ID: <OF564F4EF7.93F535D4-ON86257814.006C234C-86257814.006C6861@us.ibm.com>
Yes. Even if Rich Text Editing is not supported, at this time, we will need
to support a caret and focus ring. We also need to address what is allowed
in the canvas subtree. Those proposals are all there.


Rich Schwerdtfeger
CTO Accessibility Software Group

From:	Charles Pritchard <chuck@jumis.com>
To:	Frank Olivier <Frank.Olivier@microsoft.com>
Cc:	Richard Schwerdtfeger/Austin/IBM@IBMUS, Shawn Warren
            <swarren@aisquared.com>, Tim Lalor <tlalor@aisquared.com>,
            "janina@rednote.net" <janina@rednote.net>,
            "public-canvas-api@w3.org" <public-canvas-api@w3.org>,
            "david.bolter@gmail.com" <david.bolter@gmail.com>, Cynthia
            Shelly <cyns@microsoft.com>, "public-html-a11y@w3.org"
            <public-html-a11y@w3.org>, "oedipus@hicom.net"
Date:	01/10/2011 10:46 AM
Subject:	Re: HTML 5 Canvas Accessibility Call on January 10

Where is the IE team on implementing the drawFocusRing and caret
mechanisms? Our hope, as web developers, is that those methods be made
available for a11y purposes.

Even the cursor semantics (notably, blink rate) are useful for our
applications, apart from text editing.

On Jan 10, 2011, at 7:15 AM, Frank Olivier <Frank.Olivier@microsoft.com>

      My apologies; I won’t be able to attend the meeting on Monday

      At this point, the IE team does not think that text editing via
      canvas is a problem that we should tackle for HTML5 due to the
      inherent complexities of the problem and limited options to solve
      this correctly. The best solution for HTML5 (via tooling, education,
      author guidance) is to not fake text entry via canvas elements – much
      better native mechanisms for text editing already exist in HTML5.



      From: Richard Schwerdtfeger [mailto:schwer@us.ibm.com]
      Sent: Friday, January 07, 2011 7:36 PM
      To: Shawn Warren; Tim Lalor
      Cc: chuck@jumis.com; janina@rednote.net; public-canvas-api@w3.org;
      Frank Olivier; david.bolter@gmail.com; Cynthia Shelly;
      public-html-a11y@w3.org; oedipus@hicom.net
      Subject: RE: HTML 5 Canvas Accessibility Call on January 10

      Shawn, Tim,

      That is excellent. We are pleased AI Squared is able to attend the

      The call-in information and agenda are here:


      You will note that we also run an IRC channel where people will be
      taking minutes. You can use use the free chatzilla plug-in to Firefox
      to participate.

      The W3C IRC server is:


      The chat room is #html-a11y

      As an FYI you will see at the bottom of the page above an attached
      file called canvaseditor.html This file shows how we are using a
      shadow DOM to populate platform accessibility APIs for user drawn
      check boxes. A problem is the lack of accurate positioning
      information. Some of which is addressed in the change proposal (caret
      and focus ring) to the Canvas 2D Context API calls. The proposed
      changes to the Canvas 2D API specification are marked between <zzz>
      and </zzz> sections. Currently the DOM Accessibility API mapping of
      the shadow DOM (this is all the elements that are children of the
      <canvas> element in HTML) only is done in Beta versions of the IE 9
      browser. The shadow DOM is also participates in the keyboard
      navigation of HTML in the IE 9 implementation.

      Frank and David it will be very helpful if you are able to attend the
      call on Monday.

      Best Regards,

      Rich Schwerdtfeger
      CTO Accessibility Software Group
      [attachment "atth1n3n.binary" deleted by Richard
      Schwerdtfeger/Austin/IBM] "Shawn Warren" ---01/07/2011 10:57:26
      AM---Well I don't know much...about a lot of things really ;)...but I
      usually do know who to ask. I secur

      From: "Shawn Warren" <swarren@aisquared.com>
      To: Richard Schwerdtfeger/Austin/IBM@IBMUS
      Cc: <janina@rednote.net>, <chuck@jumis.com>, <
      public-canvas-api@w3.org>, "Tim Lalor" <tlalor@aisquared.com>
      Date: 01/07/2011 10:57 AM
      Subject: RE: Canvas Accessibility

      Well I don’t know much…about a lot of things really ;)…but I usually
      do know who to ask. I secured time from a senior engineer, Tim Lalor
      (CC), for your next Monday meeting (1/10).


      From: Richard Schwerdtfeger [mailto:schwer@us.ibm.com]
      Sent: Thursday, January 06, 2011 7:48 PM
      To: Shawn Warren
      Cc: janina@rednote.net; chuck@jumis.com; public-canvas-api@w3.org
      Subject: Canvas Accessibility

      Hi Shawn,

      I am not sure how much you know about HTML 5 <canvas> but requiring
      authors to provide positioning information for all the content found
      in canvas is a very expensive proposition. I am not sure we are going
      to be able to get that to fly with authors. Would you be willing to
      discuss options on how we can get you what you need for a Monday HTML
      Canvas Accessibility Meeting?

      This is response to your email response to my question in December:

      The canvas accessibility meeting runs at 2pm CST on Mondays for an

      Best Regards,


      Rich Schwerdtfeger
      CTO Accessibility Software Group

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Received on Monday, 10 January 2011 19:45:46 UTC

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