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Re: Request to re-open issue 131

From: Steve Faulkner <faulkner.steve@gmail.com>
Date: Sun, 18 Dec 2011 10:15:59 +0000
Message-ID: <CA+ri+VmWqmyYRdh3QxK0Tjy=tWy_Vj4tNpKFM+_EhYoeXvtLhA@mail.gmail.com>
To: Jonas Sicking <jonas@sicking.cc>
Cc: Sam Ruby <rubys@intertwingly.net>, david bolter <david.bolter@gmail.com>, Richard Schwerdtfeger <schwer@us.ibm.com>, chuck@jumis.com, Cynthia Shelly <cyns@microsoft.com>, dbolter@mozilla.com, franko@microsoft.com, Maciej Stachowiak <mjs@apple.com>, Paul Cotton <Paul.Cotton@microsoft.com>, public-canvas-api@w3.org, public-html@w3.org, public-html-a11y@w3.org
Hi Jonas,

thanks for your reply.

you wrote:
> For any feature that we introduce to the web platform we need to have
> use cases.

Laura Carlson collected information on the use cases:
http://www.w3.org/WAI/PF/HTML/wiki/Canvas_Accessibility_Use_Cases


you wrote:

>However even for hit testing and focus management, maybe we would
>design the API differently if we weren't trying to use them to built
>text editors. I really don't know enough about accessibility to fully
>answer that.

For hit testing, example uses and background is provided by  Frank
Olivier in the  doc i pointed to:
http://www.w3.org/wiki/Canvas_hit_testing

He has also publicly stated that building text editors in canvas is a
'fools errand':
http://lists.w3.org/Archives/Public/public-html/2011Nov/0210

So I think it is reasonable to assume that Franks hit testing proposal
is not motivated by the desire to build text editors in canvas.

For text baseline the rationale is outlined in the change proposal:
Modify existing Canvas 2D API to expose text baseline and facilitate
drawing of focus rings
http://www.w3.org/html/wg/wiki/ChangeProposals/FocusRingTextBaseline

in essence:
"to facilitate drawing of focus rings around text to support screen
magnifier users"

Is this minor addition to the canvas text drawing methods proposed to
facilitate the building of text editors in canvas? I think not, but
clarification from Rich/Charles would be useful.


For Focus Management the details are in the change proposal
Modify existing Canvas 2D API caret and focus ring support to drive
screen magnification
http://www.w3.org/html/wg/wiki/ChangeProposals/CaretSelection

Are the methods proposed designed to facilitate the building of text
editors in canvas? I think not, but clarification from Rich/Charles
would be useful.

regards
Stevef

On 16 December 2011 23:45, Jonas Sicking <jonas@sicking.cc> wrote:
> On Fri, Dec 16, 2011 at 3:25 AM, Steve Faulkner
> <faulkner.steve@gmail.com> wrote:
>> Hi Jonas
>>
>> you wrote:
>> "I am personally not at all interested in implementing APIs that are
>> there solely for building text editors in canvas."
>>
>> Of the proposed APIs which do you consider are solely for building text editors?
>>
>> focus management
>> http://dev.w3.org/html5/canvas-extensions/Overview.html#focus-management-1
>> caret and selection management
>> http://dev.w3.org/html5/canvas-extensions/Overview.html#caret-and-selection-management
>> extensions to text metrics
>> http://dev.w3.org/html5/canvas-extensions/Overview.html#extension-to-the-textmetrics-interface
>> hit testing
>> http://www.w3.org/wiki/Canvas_hit_testing
>
> The question can easily be answered using the age old saying: "what is
> the use case".
>
> For any feature that we introduce to the web platform we need to have
> use cases. If the only use case we can come up with are ones to
> implement text editors, then it would seem like an API "solely for
> building text editors".
>
> Based on that, it would seem like at least hit testing and focus
> management has other use cases. The rest of the APIs I don't know well
> enough to answer.
>
> However even for hit testing and focus management, maybe we would
> design the API differently if we weren't trying to use them to built
> text editors. I really don't know enough about accessibility to fully
> answer that.
>
> / Jonas



-- 
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
Received on Sunday, 18 December 2011 10:17:06 GMT

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