- From: Ian Hickson <ian@hixie.ch>
- Date: Fri, 28 Aug 2009 01:03:19 +0000 (UTC)
- To: Simon Pieters <simonp@opera.com>
- Cc: "public-html@w3.org" <public-html@w3.org>
On Mon, 17 Aug 2009, Simon Pieters wrote: > On Fri, 14 Aug 2009 03:54:08 +0200, Ian Hickson <ian@hixie.ch> wrote: > > On Thu, 6 Aug 2009, Simon Pieters wrote: > > > > > > The spec says that canvas drawImage() should throw INVALID_STATE_ERR > > > when the image isn't loaded yet or video isn't enough loaded. I > > > think this is a bad idea. > > > > > > I expect authors to just draw a video on a canvas when they see fit, > > > test locally or on a stable network, see that it works fine. Then > > > the script will stop working completely for some users because of > > > the uncaught exception when the script tries to drawImage() a video > > > that's not ready yet. > > > > > > Moreover, Opera has lazy loading of images (only loading images that > > > are rendered or have some event handlers or were created with new > > > Image() etc), so we'd probably want to just load the image when the > > > script tries to draw it instead of throwing. > > > > > > Therefore I suggest that the spec be changed to not throw > > > INVALID_STATE_ERR for drawImage() (and createPattern()). > > > > > > The method could be changed from void to return a boolean, > > > indicating whether the image was successfully drawn, so scripts can > > > detect it easily. > > > > What should createPattern() return in this situation? > > It should return null, which will be ignored when set on fillStyle and > strokeStyle. Done. (It still doesn't return false, though, since you can detect this case yourself if you really care.) -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Received on Friday, 28 August 2009 01:02:19 UTC