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Re: Example canvas element use - accessibility concerns

From: Rob Sayre <rsayre@mozilla.com>
Date: Thu, 19 Feb 2009 16:56:21 -0500
Message-ID: <499DD585.3030202@mozilla.com>
To: "John Foliot - WATS.ca" <foliot@wats.ca>
CC: 'Ian Hickson' <ian@hixie.ch>, 'David Bolter' <david.bolter@utoronto.ca>, 'Boris Zbarsky' <bzbarsky@MIT.EDU>, 'HTML WG' <public-html@w3.org>, 'W3C WAI-XTECH' <wai-xtech@w3.org>
On 2/19/09 4:18 PM, John Foliot - WATS.ca wrote:
> And/Or re-visit flawed current features?
>    

These discussions work better if you stick to technical issues, rather 
than making subjective claims rooted in your own value system. Debates 
on accessibility requirements for HTML are particularly prone to this 
kind of moralizing.

I want the accessibility of the Web to improve, and I think I understand 
and share the morals underlying your positions. I disagree that the 
tactics you're advocating will be effective. Similar rules in HTML4 are 
not effective, so the approach of mandated fallback doesn't seem 
promising to me. In Ian's current document, there is a short novel 
written on alternate content for the img element. I do not think it is 
useful for this WG to attempt to distill a single RFC 2119 imperative 
from these issues. In fact, doing so is probably counter to Section 6 of 
RFC 2119 itself.

I am interested in issues like how table summaries affect interoperation 
with screen readers. Those are technical problems this Working Group is 
in a position to fix. I don't think this is a very good venue to solve 
the social issues surrounding accessibility.

Taking a step back, I see many have raised the issue that canvas has 
poor reuse characteristics in comparison to some other Web technologies. 
This observation is correct, but that doesn't make the feature bad. The 
choice presented here is described in the REST paper, the best 
description of how the Web actually works at a high level:

http://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm#sec_5_1_7

The canvas element allows content to occur that couldn't otherwise have 
been created, and it does so without coordination in this Working Group. 
Features like that always admit the possibility that people are going to 
do things wrong as they stumble through.

- Rob
Received on Thursday, 19 February 2009 21:57:05 GMT

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