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Re: hit testing and retained graphics

From: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
Date: Tue, 21 Jun 2011 07:18:03 +0100
Message-ID: <BANLkTi=gEAMi7o2_Lq=ZuP5DOKv=EM8zgg@mail.gmail.com>
To: Charles Pritchard <chuck@jumis.com>
Cc: Frank Olivier <Frank.Olivier@microsoft.com>, Richard Schwerdtfeger <schwer@us.ibm.com>, "Mike@w3.org" <Mike@w3.org>, "david.bolter@gmail.com" <david.bolter@gmail.com>, Cynthia Shelly <cyns@microsoft.com>, "public-canvas-api@w3.org" <public-canvas-api@w3.org>, "public-html-a11y@w3.org" <public-html-a11y@w3.org>, "public-html@w3.org" <public-html@w3.org>
On Mon, Jun 20, 2011 at 5:07 PM, Charles Pritchard <chuck@jumis.com> wrote:
> I've concerns about this approach. It would mean the sub-tree is no longer
> separably viewable -- though not implemented at the moment, it is still an
> option.

I strongly agree that preventing the sub-tree being separably viewable
is problematic, indeed to the point of it being a non-starter. The
sub-tree was intended to act as an alternative for canvas like @alt is
for "img". Making it nonsensical in complex cases would discourage UAs
from making it viewable. This would prevent, for example, a user with
at least some sight and images and canvas disabled from getting access
to consistent text equivalents. This would break the specified use of
"canvas" as a dynamic
version of "img".

> A clickable area is more like an SVG path, not a CSS box.

Also true.

--
Benjamin Hawkes-Lewis
Received on Tuesday, 21 June 2011 06:18:47 GMT

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