786254 - SVG effects rendering doesn't pixel snap, causing faint vertical lines appear on some tabs

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Stuart Cook]

Attachment: Screen Shot 2012-08-28 at 11.53.21 PM.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:17.0) Gecko/17.0 Firefox/17.0
Build ID: 20120828042007

Steps to reproduce:

1. Make sure tabs-on-top is disabled. The problem occurs in either mode, but is easier to notice with tabs-on-bottom.
2. Open several tabs.


Actual results:

A faint vertical sometimes appears near the far-left or far-right of one or more tabs.


Expected results:

The tabs should appear smooth, with no visual glitches.

Comment 1

[Stuart Cook]

I'm using a mid-2009 13" MacBook Pro with a GeForce 9400M. Disabling hardware acceleration in Firefox makes no difference.

Comment 2

[Mihaela Velimiroviciu (:mihaelav)]

Stuart, could you please try reproducing this issue in safe mode(http://support.mozilla.com/en-US/kb/Safe+Mode)/with a new profile(http://support.mozilla.com/en-US/kb/Basic%20Troubleshooting#w_8-make-a-new-profile and http://support.mozilla.org/kb/Managing%20profiles) and report back whether you still see it or not?

Thank you!

Comment 3

[Stuart Cook]

I can confirm that this issue occurs in a fresh profile with no add-ons.

Comment 4

[Stuart Cook]

Bisecting nightlies, I have found that this issue does NOT occur in 2012-07-20, but DOES occur in 2012-07-21-03-05-55 and 2012-07-21-04-10-38.

Comment 5

[Stuart Cook]

This issue is still present in current nightlies as of 2012-09-07-03-05-54 (FF 18).

Comment 6

[Xidorn Quan [:xidorn] UTC+11]

I met the same issue in the nightly version as well.

Comment 7

[Xidorn Quan [:xidorn] UTC+11]

Attachment: patch

This simple patch seems to fix the problem.

Comment 8

[Markus Stange [:mstange]]

Comment on attachment 764678 [details] [diff] [review]
patch

Thanks for the patch! Unfortunately, this only works around a rendering bug. I think we should fix the real underlying bug instead.

Comment 9

[Markus Stange [:mstange]]

Attachment: testcase

Comment 10

[Xidorn Quan [:xidorn] UTC+11]

I'd like to work on this bug.

Comment 11

[Markus Stange [:mstange]]

Great!

Comment 12

[Xidorn Quan [:xidorn] UTC+11]

Attachment: testcase for mask

This bug also affects mask property.

Comment 13

[Xidorn Quan [:xidorn] UTC+11]

Attachment: patch [checkin: comment 14]

Comment 14

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/517eaa8ba87e

Comment 15

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/517eaa8ba87e

Comment 16

[Xidorn Quan [:xidorn] UTC+11]

Attachment: patch of reftest

Comment 17

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

Comment on attachment 788598 [details] [diff] [review]
patch of reftest

Review of attachment 788598 [details] [diff] [review]:
-----------------------------------------------------------------

Excellent thanks!!!

Comment 18

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/e38a476f45a4

Comment 19

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/e38a476f45a4

Comment 20

[Xidorn Quan [:xidorn] UTC+11]

Comment on attachment 779788 [details] [diff] [review]
patch [checkin: comment 14]

[Approval Request Comment]
Bug caused by (feature/regressing bug #): SVG effects support for non-SVG elements
User impact if declined: cause faint vertical lines on tabs on OS X which affects the visual experience. also cause bug 829825.
Testing completed (on m-c, etc.): a reftest has been added
Risk to taking this patch (and alternatives if risky): the patch is in the core layout component, might introduce some unknown rendering bugs.
String or IDL/UUID changes made by this patch: none

Comment 21

[bhavana bajaj [:bajaj]]

(In reply to Xidorn Quan from comment #20)
> Comment on attachment 779788 [details] [diff] [review]
> patch [checkin: comment 14]
> 
> [Approval Request Comment]
> Bug caused by (feature/regressing bug #): SVG effects support for non-SVG
> elements
> User impact if declined: cause faint vertical lines on tabs on OS X which
> affects the visual experience. also cause bug 829825.
> Testing completed (on m-c, etc.): a reftest has been added
> Risk to taking this patch (and alternatives if risky): the patch is in the
> core layout component, might introduce some unknown rendering bugs.

Given this and keeping in mind we are very close to release of Fx24 , its too late to land this change on beta. Hence not approving. I'd prefer this ride's the train or get uplifted to aurora even after a couple of days on nightly if no new regressions are found.
> String or IDL/UUID changes made by this patch: none