Re: hit testing and retained graphics

When we were work on canvas accessibility in the working group I had Shawn
Warren from AI Squared come to the call and discuss requirements. He
clearly stated that in addition to focus and caret/selection tracking (for
those limited text situations) that he needed to know where all the drawing
objects were in the drawing space that aligned with accessibles generated
from the fallback content.

Not providing access to the bounds of an object is an accessibility 101
issue for magnifiers.

Rich

Rich Schwerdtfeger
CTO Accessibility Software Group



From:	Steve Faulkner <faulkner.steve@gmail.com>
To:	Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
Cc:	Charles Pritchard <chuck@jumis.com>, Henri Sivonen
            <hsivonen@iki.fi>, Sean Hayes <Sean.Hayes@microsoft.com>, "E.J.
            Zufelt" <everett@zufelt.ca>, Paul Bakaus <pbakaus@zynga.com>,
            "Tab Atkins Jr." <jackalmage@gmail.com>, John Foliot
            <jfoliot@stanford.edu>, Charles McCathieNevile
            <chaals@opera.com>, Richard Schwerdtfeger/Austin/IBM@IBMUS,
            Cameron McCormack <cam@mcc.id.au>, Cynthia Shelly
            <cyns@microsoft.com>, "david.bolter@gmail.com"
            <david.bolter@gmail.com>, Frank Olivier
            <Frank.Olivier@microsoft.com>, "Mike@w3.org" <Mike@w3.org>,
            "public-canvas-api@w3.org" <public-canvas-api@w3.org>,
            "public-html@w3.org" <public-html@w3.org>,
            "public-html-a11y@w3.org" <public-html-a11y@w3.org>
Date:	07/03/2011 07:38 AM
Subject:	Re: hit testing and retained graphics




Hi ben,

     Also, in practice, such AT tends to have additional features like
     reading out the text in focus, re-rendering the text at higher zoom.
     Remote AT is better placed to do those things,
     and I think users would expect those features to work. So I'm not sure
     of the advantage of taking a slice of current functionality and trying
     to deliver that to local AT?

it is true screen magnifiers come in all shapes and sizes, i myself have
zoomtext 9.1 magnifier/reader. I have friends who have only the magnifier
version as they don't want or require the reading function.

Providing such a basic feature as programatic focus on areas of the canvas
will be the difference between interactive canvas content being usable or
unusable for some users.

regards
stevef


On 3 July 2011 10:49, Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
wrote:
  On Sun, Jul 3, 2011 at 7:29 AM, Steve Faulkner <faulkner.steve@gmail.com>
  wrote:
  > I thought I was clear, I have been talking about the screen magnifier
  case ,
  > not the general AT case. The only information that would need to be
  provided
  > from the remote machine is the size and position of the focused object,
  this
  > could then be used to provide the focus information to the local
  > accessibility layer.

  You're still going to need custom code to get this information out of
  custom views
  on the remote side.

  Also, in practice, such AT tends to have additional features like
  reading out the text in focus, re-rendering the text at higher zoom.
  Remote AT is better placed to do those things,
  and I think users would expect those features to work. So I'm not sure
  of the advantage of taking a slice of current functionality and trying
  to deliver that to local AT?

  --
  Benjamin Hawkes-Lewis



--
with regards

Steve Faulkner
Technical Director - TPG

www.paciellogroup.com | www.HTML5accessibility.com |
www.twitter.com/stevefaulkner
HTML5: Techniques for providing useful text alternatives -
dev.w3.org/html5/alt-techniques/
Web Accessibility Toolbar -
www.paciellogroup.com/resources/wat-ie-about.html