W3C home > Mailing lists > Public > public-html@w3.org > April 2007

Re: Canvas (was: Microsoft has now joined the HTML Working Group)

From: Maciej Stachowiak <mjs@apple.com>
Date: Fri, 6 Apr 2007 12:59:42 -0700
Message-Id: <0428091C-259F-456D-A072-8EF936C819D3@apple.com>
Cc: "public-html@w3.org" <public-html@w3.org>
To: Doug Schepers <doug.schepers@vectoreal.com>


On Apr 6, 2007, at 10:59 AM, Doug Schepers wrote:

>
> Hi, Maciej-
>
> Maciej Stachowiak wrote:
>> On Apr 5, 2007, at 3:40 PM, Doug Schepers wrote:
>>> Surely this would be handled under the W3C Graphics Activity [1],  
>>> not the HTML Activity?
>> I think new HTML elements and DOM APIs are in scope for the HTML  
>> Working Group. These may include graphics capabilities, just as  
>> Graphics Activity specs include hypertext capabilities.
>> More specifically, the charter calls for:
>> * A language evolved from HTML4 for describing the semantics of  
>> documents and applications on the World Wide Web. This will be a  
>> complete specification, not a delta specification.
>> * Document Object Model (DOM) interfaces providing APIs for such a  
>> language.
>> Clearly, <canvas> would be covered by these categories and indeed  
>> is used by HTML web applications today.
>
> I don't see how your conclusion is derived from those points in the  
> charter; that seems an overly broad interpretation.  The SVG WG in  
> the past has been accused of scope-creep, which delayed its  
> progress and publication; it's had to take pains to separate out  
> the more generalizable part of the SVG Tiny 1.2 spec to the WebAPI  
> WG.  I don't want HTML to get bogged down in this same mire.

<canvas> is already specced pretty well in WHATWG's HTML5 draft so it  
would not cause scope creep or bog anything down in any mire.

I think you are trying to say that HTML can't have support for  
graphics because that is the job of the Graphics Activity. But SVG  
has support for hypertext, and objections about its increasingly  
complex text features have been rejected by the Director. So clearly  
the partition between W3C Activities is not meant to be a firm one.

> 'canvas' is sufficiently different to the HTML functionality and  
> philosophy that I think it should be a separate specification,  
> possibly as a joint Task Force between groups from both the HTML  
> and Graphics Activities.  I honestly think it could move faster  
> this way.  It's not a huge spec, so it could be published quickly  
> and without being dependent upon the entirety of the HTML spec.

Joint task forces with the Graphics Activity do not have a track  
record of making things move faster. A notable past example, sXBL,  
resulted in failure. If the Graphics Activity wants to make major  
changes to <canvas> then a joint task force is unlikely to be  
productive. If there is no desire to make major changes to the basic  
syntax, then there's no reason not to do the work here.

I can't really see any reason to break it out other than turf issues  
or desire to delay.

> Notable differences are:
> * no DOM
> * no semantic richness
> * unable to be styled via CSS (or the like)
> * an idiosyncratic API unlike anything in HTML

I think these points apply to <img> just as much as <canvas>.

> It's really a black box.  I also don't see why its use should be  
> restricted to HTML... it could be used in SVG or WebCGM, too.

Other specs could to copy it into their own namespace or use it from  
the HTML namespace directly. Moving it out of the HTML namespace in  
HTML would probably be too big a compatbility break.

Regards,
Maciej
Received on Friday, 6 April 2007 19:59:54 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 9 May 2012 00:15:52 GMT