Bug 24668

Summary: Canvas arc gives exceptions on r<0
Product: WebKit Reporter: Dirk Schulze <krit>
Component: DOMAssignee: Dirk Schulze <krit>
Status: RESOLVED DUPLICATE    
Severity: Normal CC: ian, oliver
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: PC   
OS: OS X 10.5   
URL: http://blahbleh.com/molecools.php?name=1,2%20dimethylcyclopropane
Attachments:
Description Flags
silent return for r<0 eric: review-

Description Dirk Schulze 2009-03-18 02:55:42 PDT
Our canvas code gives exceptions on r<0 for arc. This behavior matches the spec, but breaks some sites like this above.
Comment 1 Dirk Schulze 2009-03-18 03:03:45 PDT
Created attachment 28720 [details]
silent return for r<0

patch
Comment 2 Darin Adler 2009-03-18 09:28:30 PDT
What’s our strategy on this for canvas? If the spec is wrong I think we need to get the spec fixed too, and not just change our implementation. Have we been doing this same type of thing for other canvas issues?
Comment 3 Dirk Schulze 2009-03-18 10:43:00 PDT
It's ok to return if r<0, but there is no need to throw an exception here. The same for arcTo.
It's maybe the best way to adjust the spec.
Comment 4 Eric Seidel (no email) 2009-03-26 11:09:15 PDT
Comment on attachment 28720 [details]
silent return for r<0

We should match the spec.  Even if that means the spec should be changed here.  This change would also require a test case (preferably a new js-style test).

I suggest you add a test to check our behavior regardless.  Then at least we know when we change our behavior later to match any changes in the spec.
Comment 5 Oliver Hunt 2009-03-26 14:20:06 PDT
Comment on attachment 28720 [details]
silent return for r<0

dirk and i already discussed this -- he's going to email whatwg's mailing list to get the spec changed.
Comment 6 Oliver Hunt 2009-03-26 14:21:01 PDT
Comment on attachment 28720 [details]
silent return for r<0

Oh, needs a layout test :D
Comment 7 Dirk Schulze 2009-04-08 13:48:49 PDT
Sorry for my absence. I'll upload a layout test in the next days.
Comment 8 Eric Seidel (no email) 2009-04-29 14:12:08 PDT
Comment on attachment 28720 [details]
silent return for r<0

Marking as r- due to lack of layout test.
Comment 9 Dirk Schulze 2009-04-30 03:52:40 PDT
Ian Hixie denied the change of the spec. (for the moment ;-))

http://www.nabble.com/Canvas---Exception-on-arc-with-negative-radius-td22748785.html
Comment 10 Dirk Schulze 2009-05-02 15:16:35 PDT
Opened a bug in bugzilla.mozilla.org (https://bugzilla.mozilla.org/show_bug.cgi?id=491150). Let's see their opinion.
Comment 11 Dirk Schulze 2010-05-24 12:06:47 PDT

*** This bug has been marked as a duplicate of bug 37176 ***