1489099 - polygons not drawn or visible edges with Firefox 62

Status: RESOLVED FIXED

(Core :: Graphics: CanvasWebGL, defect)

Description

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Firefox 62.0 64-bit on Windows 8.1

https://skfb.ly/6BrUp has some polygons from the roof missing and one can see some gaps in the edges of the sides.

Bisection shows this started between 62.0 beta 18 and beta 19. Pushlog: https://hg.mozilla.org/releases/mozilla-beta/pushloghtml?fromchange=FIREFOX_62_0b18_RELEASE&tochange=FIREFOX_62_0b19_RELEASE

This looks like a regression from bug 1477817. Despite central (including beta 63) and ESR having also been patched, I am unable to reproduce this with those channels.

Comparison of the troubleshooting shows that the WebGL driver extensions additional have GL_KHR_robust_buffer_access_behavior in 62.0b19+

Comment 1

[Ryan VanderMeulen [:RyanVM]]

Assuming this follows the same pattern of bug 1485441, there's a decent chance Beta63 will also reproduce, so setting the tracking flags accordingly. Also, fixed for 62.0.1 via backout.

https://hg.mozilla.org/releases/mozilla-release/rev/4e6207ecd553

Comment 2

[Kelsey Gilbert [:jgilbert]]

Please post images showing the issue.

Comment 3

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Attachment: polygon issues

Sorry, lost the attachment during bug creation when I had to go back in the tab's history and resubmit.

Comment 4

[Julien Cristau [:jcristau] (back April 22)]

Fixing status flags.  Bug 1477817 was backed out of mozilla-release only.

Comment 5

[billisenberger]

The linked image shows what the model should look and what it looks like in FF6.2.

http://digital-mapping.net/Sketchfab/2018/Firefox62.jpg

Comment 6

[billisenberger]

I wrote FF6.2 in previous post, should be 62.0.

More info on this thread:
https://support.mozilla.org/en-US/questions/1232932#answer-1151942

Comment 7

[stephane]

(Sketchfab dev)

The problem seems to be specific to TRIANGLE_STRIPS on WEBGL1

https://sketchfab.com/models/7fd9a70e053a4fec922b436758707c5f
^ has the issue

https://sketchfab.com/models/7fd9a70e053a4fec922b436758707c5f?webgl2=1
^ works fine

https://sketchfab.com/models/7fd9a70e053a4fec922b436758707c5f?force_triangles=1
^ works fine

We might hotfix a temporary the issue by targeting firefox, a reliable url to reproduce the issue could be:
https://sketchfab.com/models/7fd9a70e053a4fec922b436758707c5f?force_triangles=0&webgl2=0

Comment 8

[[:philipp]]

another sample site which shows some rendering defects according to a sumo report:
http://www.cadituk.com/satellite/C3D/cortona/MAC/2/test.htm

Comment 9

[Pascal Chevrel:pascalc (PTO until April 26)]

I can't reproduce the bug neither in Beta 63 nor Nightly 64 with the URLs provided in comments #7 and #8 (Linux).

Brindusa, could you investigate if this regression impacts 63 beta on all platforms? Thanks

Comment 10

[stephane]

My bad, I went a bit too fast when fixing the bug on our side and forgot to respect the force_triangles=0 flag :(.

So, basically when we detect that we are on firefox, we convert our TRIANGLE_STRIPS to TRIANGLES (drawElements in both cases).

On next release (next week normally), I'll add back the force_triangles=0 enforcement for debugging purposes.

This bug report seems like a duplicate of https://bugzilla.mozilla.org/show_bug.cgi?id=1487847

Comment 11

[Kelsey Gilbert [:jgilbert]]

My guess here is that ANGLE messes up index fetch when contexts are created with RBAB.

Comment 12

[Gyula Palko[:gpalko]]

I've tested this and I couldn't reproduce the issue on Nightly 64 and Beta 63.
Environments covered: Win10 x64, Win8 x64, Ubuntu 16.04, MacOS 10.12

Comment 13

[[e-mail]]

This may be the same issue. 
This picture is of the error on Windows 10 64 bit:
http://service.mtdproducts.com/win10capture.JPG

Here is the same animation at the same point in time on a Window 7 64 bit machine:
http://service.mtdproducts.com/win7capture.JPG

For some reason it work on Windows 7 but not Windows 10.

Comment 14

[stephane]

(For information, we added back the ?force_triangles=0 debug option, I can confirm the url https://sketchfab.com/models/7fd9a70e053a4fec922b436758707c5f?force_triangles=0 reproduces the issue)

Comment 15

[Julien Cristau [:jcristau] (back April 22)]

This should be fixed in firefox 62.0.2 which will ship in the next few days.

Comment 17

[Masatoshi Kimura [:emk]]

Can anyone still reproduce this? (I guess not.)

Comment 18

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Looks as expected with 62.0.3, 63.0b12 and latest Nightly, all on Windows 8.1 which also had been used to reproduce the issue in comment 0.

Comment 19

[Pascal Chevrel:pascalc (PTO until April 26)]

(In reply to Sebastian Hengst [PTO+workweek 2018-09-22 - 2018-10-08][:aryx] (needinfo on intermittent or backout) from comment #18)
> Looks as expected with 62.0.3, 63.0b12 and latest Nightly, all on Windows
> 8.1 which also had been used to reproduce the issue in comment 0.

Marking as fixed as a consequence, thanks.