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

Rik Cabanier cabanier at gmail.com
Fri Mar 1 14:45:09 PST 2013

On Fri, Mar 1, 2013 at 2:40 PM, Glenn Maynard <glenn at zewt.org> wrote:

> 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.)
Sorry about being unclear. Yes, I meant in addition of.
- add your suggested step 1
- change HTMLImageElement from original step 2 to CanvasImageSource

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