[html4all] Discussion: "Accept requirement for immediate mode graphics a la canvas element"

[Anne van Kesteren]

On Wed, 21 Nov 2007 16:34:24 +0100, Charles McCathieNevile  
<chaals at opera.com> wrote:
>> Would you talk me through your reading of the draft
>> spec. in support of that ?  I would like to belive
>> that it is true, but failed to find evidence in
>> the draft spec. as currently written.
>
> I haven't looked for a while, but last I did you could just put content
> inside
>
> <canvas> </canvas>
>
> tags if you want.

Relevant quotes from  
http://www.whatwg.org/specs/web-apps/current-work/#canvas

"Authors should not use the canvas element in a document when a more  
suitable element is available. For example, it is inappropriate to use a  
canvas element to render a page heading: if the desired presentation of  
the heading is graphically intense, it should be marked up using  
appropriate elements (typically h1) and then styled using CSS and  
supporting technologies such as XBL.

When authors use the canvas element, they should also provide content  
that, when presented to the user, conveys essentially the same function or  
purpose as the bitmap canvas. This content may be placed as content of the  
canvas element. The contents of the canvas element, if any, are the  
element's fallback content.

In interactive visual media with scripting enabled, the canvas element is  
an embedded element with a dynamically created image.

In non-interactive, static, visual media, if the canvas element has been  
previously painted on (e.g. if the page was viewed in an interactive  
visual medium and is now being printed, or if some script that ran during  
the page layout process painted on the element), then the canvas element  
must be treated as embedded content with the current image and size.  
Otherwise, the element's fallback content must be used instead.

In non-visual media, and in visual media with scripting disabled, the  
canvas element's fallback content must be used instead."


-- 
Anne van Kesteren
<http://annevankesteren.nl/>
<http://www.opera.com/>