749467 - canvas renders incorrectly

Status: VERIFIED FIXED

(Core :: Graphics: Canvas2D, defect)

Description

[ashvinjayaram]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.162 Safari/535.19

Steps to reproduce:

Reduced the issue I was having to this test case: http://jsfiddle.net/una3y/


Actual results:

Firefox 12 renders this differently to all other browsers, including older versions of Firefox

Comment 1

[Alice0775 White]

Confirmed on 
http://hg.mozilla.org/mozilla-central/rev/cc5254f9825f
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/20120426 Firefox/15.0a1 ID:20120426030504

And gfx.canvas.azure.enabled = false helps.


Regression window(m-c):
Works:
http://hg.mozilla.org/mozilla-central/rev/450e4d9ea2d5
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0a1) Gecko/20110624 Firefox/7.0a1 ID:20110625025936
Fails:
http://hg.mozilla.org/mozilla-central/rev/48ad4ffc4230
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0a1) Gecko/20110625 Firefox/7.0a1 ID:20110625030821
Pushlog:
http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=450e4d9ea2d5&tochange=48ad4ffc4230



Regression window(m-i):
Works:
http://hg.mozilla.org/integration/mozilla-inbound/rev/c65f1fb0449d
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0a1) Gecko/20110624 Firefox/7.0a1 ID:20110624094307
Fails:
http://hg.mozilla.org/integration/mozilla-inbound/rev/46c3d095bc75
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0a1) Gecko/20110624 Firefox/7.0a1 ID:20110624104626
Pushlog:
http://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=c65f1fb0449d&tochange=46c3d095bc75


Regressed by:
Bug 651858

Comment 2

[ashvinjayaram]

Adding an extra ctx.stroke() fixes this for now: http://jsfiddle.net/una3y/1/

Comment 3

[Bas Schouten (:bas.schouten)]

Attachment: Properly mark mPathTransformWillUpdate false

So the problem here is that ::EnsureWritablePath will create a device space path builder. But it will never mark mPathTransformWillUpdate false to indicate the changing transform (caused by the restore) has been dealt with. This patch fixes that, reftest incoming.

Comment 4

[Bas Schouten (:bas.schouten)]

Attachment: Add reftest for path continuation after transform changes

Comment 5

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Need to get this regression fix everywhere.

Comment 6

[Bas Schouten (:bas.schouten)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/877276e291b8
https://hg.mozilla.org/integration/mozilla-inbound/rev/5abd27624d84

Comment 7

[:Ms2ger (he/him; ⌚ UTC+1/+2)]

https://hg.mozilla.org/mozilla-central/rev/5abd27624d84
https://hg.mozilla.org/mozilla-central/rev/877276e291b8

Comment 8

[Alex Keybl [:akeybl]]

It's not yet clear whether this would be a ride along for a FF12 chemspill - we'll evaluate at that time. We should, however, get this fix on Aurora and Beta already.

Comment 9

[Alex Keybl [:akeybl]]

(In reply to Robert O'Callahan (:roc) (Mozilla Corporation) from comment #5)
> Need to get this regression fix everywhere.

Actually, can we have more insight into why you feel this regression from FF7 needs to land on all branches?

Comment 10

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Because Web compatibility breakage regressions are really bad?

Comment 11

[Alex Keybl [:akeybl]]

(In reply to Robert O'Callahan (:roc) (Mozilla Corporation) from comment #10)
> Because Web compatibility breakage regressions are really bad?

Yes, they're bad. But "Need to get this regression fix everywhere" implies urgency undue to a regression this old. We'll evaluate risk/reward when the fix is ready.

Comment 12

[Robert O'Callahan (:roc) (email my personal email if necessary)]

The fix has already landed on mozilla-central. What else are we waiting for?

Comment 13

[Bas Schouten (:bas.schouten)]

Comment on attachment 618920 [details] [diff] [review]
Properly mark mPathTransformWillUpdate false

[Approval Request Comment]
Regression caused by (bug #): 
User impact if declined: 
Testing completed (on m-c, etc.): 
Risk to taking this patch (and alternatives if risky):
String changes made by this patch:

Comment 14

[Bas Schouten (:bas.schouten)]

(In reply to Bas Schouten (:bas) from comment #13)
> Comment on attachment 618920 [details] [diff] [review]
> Properly mark mPathTransformWillUpdate false
> 
> [Approval Request Comment]
> Regression caused by (bug #):
Bug 651858 
> User impact if declined:
Canvas rendering incorrect
> Testing completed (on m-c, etc.):
Landed on m-c
> Risk to taking this patch (and alternatives if risky): 
Low risk - I don't see any serious risks.
> String changes made by this patch:
None

Comment 15

[Bas Schouten (:bas.schouten)]

Comment on attachment 618921 [details] [diff] [review]
Add reftest for path continuation after transform changes

If we uplift the patch we might want to uplift the test as well, not sure what the policy is there.

Comment 16

[Alex Keybl [:akeybl]]

Comment on attachment 618920 [details] [diff] [review]
Properly mark mPathTransformWillUpdate false

[Triage Comment]
Given the risk evaluation, approving the fix for this regression for both Aurora 14 and Beta 13. If we see any regressions over the next 3 weeks, we'll be quick to back this out (although that's unexpected).

Comment 17

[Robert O'Callahan (:roc) (email my personal email if necessary)]

I will land this.

Comment 18

[Robert O'Callahan (:roc) (email my personal email if necessary)]

https://hg.mozilla.org/releases/mozilla-aurora/rev/046f1d37eea0
https://hg.mozilla.org/releases/mozilla-aurora/rev/8f5e65a6d540

https://hg.mozilla.org/releases/mozilla-beta/rev/935ca7392a0c
https://hg.mozilla.org/releases/mozilla-beta/rev/7ed8711c7249

Comment 19

[Ioana (away)]

The automated test for this bug passed on all OSs on Firefox 13.0 beta:
https://tbpl.mozilla.org/php/getParsedLog.php?id=12159689&full=1&branch=mozilla-beta
https://tbpl.mozilla.org/php/getParsedLog.php?id=12163243&full=1&branch=mozilla-beta
https://tbpl.mozilla.org/php/getParsedLog.php?id=12164769&full=1&branch=mozilla-beta

I have also tried to verify this fix manually but I got the same image rendered on:
IE9
Chrome 19.0.1084.46
Firefox 11.0
Firefox 12.0
Firefox 13.0 beta 6.

If anyone can reproduce this issue on pre-fix builds, please try to verify this issue manually.

Comment 20

[u279076]

Alice, would you mind confirming if this is fixed for you? It seems we have inconsistent results as per comment 19.

Comment 21

[Alice0775 White]

I can reproduce the Issue in
http://hg.mozilla.org/releases/mozilla-release/rev/a294a5b4f12d
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0 ID:20120420145725

I cannot Reproduce anymore in
http://hg.mozilla.org/releases/mozilla-beta/rev/5de6e4bd8ede
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:13.0) Gecko/20100101 Firefox/13.0 ID:20120523114940
http://hg.mozilla.org/releases/mozilla-aurora/rev/89176b6d643c
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:14.0) Gecko/20120530 Firefox/14.0a2 ID:20120530042008
http://hg.mozilla.org/mozilla-central/rev/65fa5cb6f79c
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/15.0 Firefox/15.0a1 ID:20120530030519

Comment 22

[u279076]

Thanks a lot, Alice!