Re: Final changes to Hit Regions before return to Last Call

OK. That is as I remember us agreeing on in the last meeting I attended.

Continue dispatching the event, but with the updated event object and
target as given in the above steps.

This step was not clear that when you said target you mean the ID and not
the target object.

Thank you for the clarification.

OK. Back to vacation.


Rich Schwerdtfeger



From:	Mark Sadecki <mark@w3.org>
To:	Richard Schwerdtfeger/Austin/IBM@IBMUS
Cc:	"public-canvas-api@w3.org" <public-canvas-api@w3.org>, Jay
            Munro <jaymunro@microsoft.com>
Date:	04/16/2014 03:47 PM
Subject:	Re: Final changes to Hit Regions before return to Last Call



Hi Rich,

On 4/16/14, 4:36 PM, Richard Schwerdtfeger wrote:
> I am on vacation and with limited access to email but didn't we decide to
> dispatch the event to the actual control in v1.0? Rather, I thought the
id of
> the target would be included in The dispatch to the canvas element.

We came to a resolution on 31 MAR 2014 [1] that the canvas element would
receive
the event.  We further discussed the mechanics of this approach with
Philippe on
14 APR 2014 and concluded that the ID of the region will be included in
that
event and the developer can do what they wish with it [2].  This should be
forward compatible and easily implementable for L1.

[1] http://www.w3.org/2014/03/31-1-html-a11y-minutes.html#item05
[2] http://www.w3.org/2014/04/14-html-a11y-minutes.html#item03
>
> Rich
>
> Sent from my iPad
>
>> On Apr 15, 2014, at 3:53 PM, "Mark Sadecki" <mark@w3.org> wrote:
>>
>> The following changes were discussed during the canvas accessibility sub
group
>> call on 14 APR 2014
>>
>> <http://www.w3.org/2014/04/14-html-a11y-minutes.html>
>>
>> ## The region representing the control
>>
>> * Add a step that handles a null value for control, similar to the one
that is
>> defined for ID, just before the existing step 1.
>>
>> > "If control is null, return nothing and abort these steps."
>>
>> ## The region for a pixel
>>
>> * Change "set of pixels" to "path" in step 2 and link "path" to
>> <
http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/#hit-region%27s-path
>
>>
>> ## addHitRegion()
>>
>> * add the following step after step 3 (Let specified pixels be the
pixels
>> contained in source path.)
>>
>> > "Remove from specified pixels any pixels not contained within the
clipping
>> region."
>>
>> ## clearHitRegions()
>>
>> * Remove Step 2 RE: Garbage Collection
>>
>> ## MouseEvent
>>
>> We agreed that we would eliminate event retargeting altogether and just
pass the
>> event.region to the canvas element.  This would require the following
changes:
>>
>> * Revert order of steps and add step for handling a canvas element with
no hit
>> region list.  The first 4 steps should read as follows:
>>
>>    1. If the pointing device is not indicating a pixel on the canvas,
act as
>> normal and abort these steps.
>> -> 2. If the canvas element has no hit region list, act as normal and
abort
>> these steps.
>>    3. Let pixel be the pixel indicated by the pointing device.
>>    4. Let region be the hit region that is the region for the pixel
pixel on
>> this canvas element's bitmap, if any.
>>
>> * The following steps are no longer required (the numbers will be
shifted by one
>> if the above steps have been followed) and should be removed:
>>
>> 7. Let control be the region's control, if any.
>> 8. Let the canvas element be the target of the event object, unless
there is a
>> control, then target the control instead.
>> 9. Continue dispatching the event, but with the updated event object and
target
>> as given in the above steps.
>>
>> --
>> Mark Sadecki
>> Web Accessibility Engineer
>> World Wide Web Consortium, Web Accessibility Initiative
>> Telephone: +1.617.715.4017
>> Email: mark@w3.org
>> Web: http://w3.org/People/mark
>>
>


--
Mark Sadecki
Web Accessibility Engineer
World Wide Web Consortium, Web Accessibility Initiative
Telephone: +1.617.715.4017
Email: mark@w3.org
Web: http://w3.org/People/mark