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Re: hit testing and retained graphics

From: paniz alipour <alipourpaniz@gmail.com>
Date: Fri, 8 Jul 2011 11:11:47 +0430
Message-ID: <CADfq16iup3SFHwhqDYEPsY9iRww3Q=7UhFOJGopGTTNYnFAiqA@mail.gmail.com>
To: Charles Pritchard <chuck@jumis.com>
Cc: Richard Schwerdtfeger <schwer@us.ibm.com>, "cyns@exchange.microsoft.com" <cyns@exchange.microsoft.com>, "david.bolter@gmail.com" <david.bolter@gmail.com>, "franko@microsoft.com" <franko@microsoft.com>, "Mike@w3.org" <Mike@w3.org>, "public-canvas-api@w3.org" <public-canvas-api@w3.org>, "public-canvas-api-request@w3.org" <public-canvas-api-request@w3.org>, "public-html@w3.org" <public-html@w3.org>, "public-html-a11y@w3.org" <public-html-a11y@w3.org>
I knew Charles,but I remember that shadow Dom and fallback content sub-tree
is just supported in IE9.Am I right?

On Fri, Jul 8, 2011 at 10:51 AM, Charles Pritchard <chuck@jumis.com> wrote:

> IE8 does not support canvas; it shows the fallback content.
>
>
>
> On Jul 7, 2011, at 11:18 PM, paniz alipour <alipourpaniz@gmail.com> wrote:
>
> Hi Richard,
>
> There was some thing marvelous! As I found out shadow Dom or fallback
> content was just supported in IE9 ,but I saw that it is run in IE8 too.
>
> I mean your sample that you had sent it for me.
>
> Am I right ? What has happened?
>
> Thanks
>
> On Thu, Jul 7, 2011 at 6:45 PM, Richard Schwerdtfeger <<schwer@us.ibm.com>
> schwer@us.ibm.com> wrote:
>
>> Yes, the author draws the widget on the canvas based on the information in
>> the canvas subtree.
>>
>> If you don't use the subtree it won't be in the keyboard navigation order
>> and you can't provide the accessibility information
>>
>> From the HTML 5 spec on canvas:
>> <http://dev.w3.org/html5/spec/the-canvas-element.html#the-canvas-element>
>> http://dev.w3.org/html5/spec/the-canvas-element.html#the-canvas-element
>>
>> "When a *canvas*<http://dev.w3.org/html5/spec/the-canvas-element.html#the-canvas-element>element
>> *represents* <http://dev.w3.org/html5/spec/rendering.html#represents> *embedded
>> content*<http://dev.w3.org/html5/spec/content-models.html#embedded-content>,
>> the user can still focus descendants of the *canvas*<http://dev.w3.org/html5/spec/the-canvas-element.html#the-canvas-element>element (in the
>> *fallback content*<http://dev.w3.org/html5/spec/content-models.html#fallback-content>).
>> When an element is focused, it is the target of keyboard interaction events
>> (even though the element itself is not visible). This allows authors to make
>> an interactive canvas keyboard-accessible: authors should have a one-to-one
>> mapping of interactive regions to focusable elements in the *fallback
>> content*<http://dev.w3.org/html5/spec/content-models.html#fallback-content>.
>> (Focus has no effect on mouse interaction events.) *[DOMEVENTS]*<http://dev.w3.org/html5/spec/the-canvas-element.html#DOMEVENTS>
>> "
>>
>> Attached is a basic example:
>>
>>
>> *(See attached file: CanvasEditor.html)*
>>
>> Rich Schwerdtfeger
>> CTO Accessibility Software Group
>>
>> <graycol.gif>paniz alipour ---07/07/2011 09:04:12 AM---Hi Richard, Yes I
>> get your purpose,except one part :
>>
>>
>> From: paniz alipour < <alipourpaniz@gmail.com>alipourpaniz@gmail.com>
>> To: Richard Schwerdtfeger/Austin/IBM@IBMUS
>> Cc: <chuck@jumis.com>chuck@jumis.com, <cyns@exchange.microsoft.com>
>> cyns@exchange.microsoft.com, <david.bolter@gmail.com>
>> david.bolter@gmail.com, <franko@microsoft.com>franko@microsoft.com,
>> <Mike@w3.org>Mike@w3.org, <public-canvas-api@w3.org>
>> public-canvas-api@w3.org, <public-canvas-api-request@w3.org>
>> public-canvas-api-request@w3.org, <public-html@w3.org>public-html@w3.org,
>> <public-html-a11y@w3.org>public-html-a11y@w3.org
>> Date: 07/07/2011 09:04 AM
>>
>> Subject: Re: hit testing and retained graphics
>> Sent by: <public-canvas-api-request@w3.org>
>> public-canvas-api-request@w3.org
>> ------------------------------
>>
>>
>>
>> Hi Richard,
>>
>> Yes I get your purpose,except one part :
>>
>> * You control the drawing * ?!
>>
>>
>> in this sentence:
>> If you wanted to create a canvas rendering of a checkbox in the fallback
>> content, on the canvas that was 70X70 you can do it. You control the drawing
>>
>> and some thing else if a developer doesn't use sub-tree in shadow DOM?
>> what does happen?
>>
>>
>> Thanks
>>
>>
>> On Thu, Jul 7, 2011 at 6:25 PM, Richard Schwerdtfeger <*schwer@us.ibm.com
>> * <schwer@us.ibm.com>> wrote:
>>
>>    Hi Paniz,
>>
>>    I am not sure if I am answering your question but you could create
>>    these objects on canvas and create equivalents in the canvas subtree whereby
>>    the canvas is a rendering of the HTML element in the canvas subtree and you
>>    can give it any size and dimension you want. All the elements in canvas
>>    subtree could be placed in the keyboard navigation order. If you wanted to
>>    create a canvas rendering of a checkbox in the fallback content, on the
>>    canvas that was 70X70 you can do it. You control the drawing. Accessibility
>>    wise I don't yet have a way to communicate those bounds to the accessibility
>>    API. This is what we have been discussing. We have been discussing creating
>>    a drawing path on canvas that represents the bounds of the object, binding
>>    it to the canvas subtree element (which is in the keyboard navigation
>>    order). In doing so we would have the user agent to do hit testing on the
>>    drawing objects in canvas and pass the pointing event to the corresponding
>>    object in the accessibility subtree. The bounds of the object used for hit
>>    testing would be passed to the corresponding accessible object
>>    (corresponding the to the DOM element in the subtree). Now a magnifier would
>>    know how to zoom to the corresponding 70x70 checkbox on the canvas.
>>
>>    To be honest, this is not new. This is how desktops like Windows work.
>>    You have a graphic on the screen bound to a COM object which supports MSAA.
>>    The MSAA bounding rectangle is retrieved from the retained mode graphic.
>>    We are arguing for putting this capability into canvas.
>>
>>
>>    Rich
>>
>>
>>    Rich Schwerdtfeger
>>    CTO Accessibility Software Group
>>
>>    <graycol.gif>paniz alipour ---07/07/2011 08:42:16 AM---Hi Richard, I
>>    mean for example I have an interaction UI on canvas as like web pages,
>>
>>
>>
>>    From: paniz alipour <*alipourpaniz@gmail.com* <alipourpaniz@gmail.com>
>>    >
>>    To: Richard Schwerdtfeger/Austin/IBM@IBMUS
>>    Cc: *chuck@jumis.com* <chuck@jumis.com>, *cyns@exchange.microsoft.com*<cyns@exchange.microsoft.com>,
>>    *david.bolter@gmail.com* <david.bolter@gmail.com>, *
>>    franko@microsoft.com* <franko@microsoft.com>, *Mike@w3.org*<Mike@w3.org>,
>>    *public-canvas-api@w3.org* <public-canvas-api@w3.org>, *
>>    public-html@w3.org* <public-html@w3.org>, *public-html-a11y@w3.org*<public-html-a11y@w3.org>
>>    Date: 07/07/2011 08:42 AM
>>
>>    Subject: Re: hit testing and retained graphics
>>    Sent by: *public-canvas-api-request@w3.org*<public-canvas-api-request@w3.org>
>>
>>    ------------------------------
>>
>>
>>
>>
>>    Hi Richard,
>>
>>    I mean for example I have an interaction UI on canvas as like web
>>    pages,
>>
>>    textbox,radiobutton ,checkbox,.... .I want to know these elements that
>>    are drawn or are images on canvas
>>
>>    could be incredible,Of course they can but in your opinion how many
>>    percent it is possible(forexample checkbox with height 70 and width 70)
>>
>>    Best Regards
>>
>>    On Thu, Jul 7, 2011 at 6:02 PM, Richard Schwerdtfeger <*
>>    schwer@us.ibm.com* <schwer@us.ibm.com>> wrote:
>>    Hi Paniz,
>>
>>       I am not quite following you. Could you please provide more detail?
>>
>>       Thanks,
>>
>>
>>       Rich
>>
>>
>>       Rich Schwerdtfeger
>>       CTO Accessibility Software Group
>>
>>       <graycol.gif>paniz alipour ---07/07/2011 06:32:18 AM---Hello to
>>       all, Maybe you think that this question is not related to this discussion,
>>
>>
>>       From: paniz alipour <*alipourpaniz@gmail.com*<alipourpaniz@gmail.com>
>>       >
>>       To: Richard Schwerdtfeger/Austin/IBM@IBMUS
>>       Cc: *chuck@jumis.com* <chuck@jumis.com>, *franko@microsoft.com*<franko@microsoft.com>,
>>       *Mike@w3.org* <Mike@w3.org>, *david.bolter@gmail.com*<david.bolter@gmail.com>,
>>       *cyns@exchange.microsoft.com* <cyns@exchange.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>
>>       Date: 07/07/2011 06:32 AM
>>
>>       Subject: Re: hit testing and retained graphics
>>
>>       ------------------------------
>>
>>
>>
>>
>>       Hello to all,
>>
>>       Maybe you think that this question is not related to this
>>       discussion,
>>
>>       But I want to know whether the web widget that are located on
>>       canvas,
>>
>>       are they incredible .I mean a check box with height 70,weight 70,
>>
>>       or no it will design as the common web widget on websites?
>>
>>       Thanks
>>
>>       On Fri, Jun 17, 2011 at 11:11 PM, Richard Schwerdtfeger <*
>>       schwer@us.ibm.com* <schwer@us.ibm.com>> wrote:
>>          Charles, Frank, Mike,
>>
>>          I am back from vacation. How far do we need to go with hit
>>          testing? Right now I am looking at associating a closed draw path with a DOM
>>          object in the canvas subtree. We would then need to address the routing of
>>          pointing device input events to the DOM object. The drawing path can be used
>>          to provide bound information to platform accessibility API.
>>
>>          Do we need to bind any other drawing properties to the canvas
>>          object - similar to the way device context's are handled on graphic
>>          subsystems like Windows?
>>
>>          Mike, I am including you as before I went on vacation you
>>          indicated that a number of developers desired this feature and wanted to be
>>          involved.
>>
>>          Rich
>>
>>
>>          Rich Schwerdtfeger
>>          CTO Accessibility Software Group
>>
>>
>>
>>
>>       --
>>       Paniz Alipour
>>
>>
>>
>>
>>
>>
>>    --
>>    Paniz Alipour
>>
>>
>>
>>
>>
>>
>> --
>> Paniz Alipour
>>
>>
>
>
> --
> Paniz Alipour
>
>


-- 
Paniz Alipour
Received on Friday, 8 July 2011 06:42:29 UTC

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