W3C home > Mailing lists > Public > public-html-a11y@w3.org > March 2011

Re: feedback requested: Canvas change for improved hit testing that also facilitates accessibility

From: Richard Schwerdtfeger <schwer@us.ibm.com>
Date: Wed, 30 Mar 2011 10:39:08 -0500
To: Boris Zbarsky <bzbarsky@mit.edu>
Cc: chuck@jumis.com, cyns@exchange.microsoft.com, david.bolter@gmail.com, faulkner.steve@gmail.com, franko@microsoft.com, public-canvas-api@w3.org, public-html@w3.org, public-html-a11y@w3.org, public-html-request@w3.org
Message-ID: <OF17F8871D.3D67E8D8-ON86257863.0054BB0D-86257863.0055FAF3@us.ibm.com>

Thanks Boris. Sorry for being a pest but I really want developers to work
through the issues.

So, you would do the following:

- Assign the a closed draw path to an element in fallback content:
setClickableRegion(element). This immediately makes the association and
places it at the bottom of the list.
- Any time you draw the element it moves it to the top of the list.
- If the fallback element is removed the association would need to go away.
I did not address that so I will need to add that to the proposal
- When a pointer event (click, etc.) goes to the fallback element the
normal capture/bubbling event processing would apply


Rich Schwerdtfeger
CTO Accessibility Software Group

From:	Boris Zbarsky <bzbarsky@mit.edu>
To:	Richard Schwerdtfeger/Austin/IBM@IBMUS
Cc:	public-canvas-api@w3.org, public-html@w3.org,
            public-html-a11y@w3.org, public-html-request@w3.org,
            chuck@jumis.com, cyns@exchange.microsoft.com,
            david.bolter@gmail.com, faulkner.steve@gmail.com,
Date:	03/30/2011 10:05 AM
Subject:	Re: feedback requested: Canvas change for improved hit testing
            that also   facilitates accessibility

On 3/30/11 10:55 AM, Richard Schwerdtfeger wrote:
> Seeing as nobody has commented can we assume that developers have no
> problem with our totally changing the canvas 2D API to support clickable
> regions?

It might just mean that people don't read their mailing list spam every
few hours.

 From reading over your proposal, I'm not sure I follow how it would
behave in the face of DOM mutations (e.g. elements being removed from
the fallback content).

Or put another way, once you draw, you're permanently attaching some
element to the canvas, right?  Or is that not the proposal?


(image/gif attachment: graycol.gif)

Received on Wednesday, 30 March 2011 15:40:20 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 19:55:53 UTC