[whatwg] A question about the drawimage() canvas function

Glenn Maynard glenn at zewt.org
Fri Mar 1 14:40:56 PST 2013

On Fri, Mar 1, 2013 at 4:24 PM, Rik Cabanier <cabanier at gmail.com> wrote:

> I think it should say:
>> 1. If the image argument is an HTMLImageElement object in the broken
>> state, then throw an InvalidStateError exception, return aborted and abort
>> these steps.
>> 2. If the image argument is an HTMLImageElement object that is not fully
>> decodable, or if the image argument is an HTMLVideoElement object whose
>> readyState attribute is either HAVE_NOTHING or HAVE_METADATA, then return
>> bad and abort these steps.
>> 3. (original step 2, unchanged)
> I think original step 2 should be updated to *CanvasImageSource* instead
> of HTMLImageElement. This is certainly how webkit implemented it.

That sounds fine too, as long as you mean in addition to the above and not
instead of.

(If you mean instead of, I disagree.  As far as throwing or not throwing
based on the broken or loading state question, it seems like WebKit should
change to match FF and IE, since those two already agree, and WebKit also
agrees with one of the two drawImage overloads tested.)

Glenn Maynard

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