1509272 - Bug in effect Zoom In / Out

Status: RESOLVED FIXED

(Core :: Web Painting, defect, P2)

Description

[Rodrigo Alineri]

Attachment: Firefox Bug.mp4

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0

Steps to reproduce:

I accessed the home page of the site http://ead.cneceduca.com.br


Actual results:

A zoom in / out animation failure occurs, which was not the case in the previous version.


Expected results:

The effect should not show the "white bands", as can be seen in other browsers.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=985e470b78d88f0edd223118cfcbb9b8b5670b1a&tochange=4ef564f7ffe2c6c138513d314e87d0332002cd6a

Comment 2

[Miko Mynttinen]

Cannot reproduce this on macOS. Did the page change, or is the bug fixed?

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Attachment: Testcase that reproduces the issue.

The page changed and they worked-around the bug by de-accelerating the animation on Firefox (see the zoomFirefox stuff).

I ended up with this test-case that shows the issue on non-webrender.

Comment 4

[Miko Mynttinen]

Attachment: testcase.html

Further reduced testcase. Flipping layout.display-list.retain;false fixes the problem.

Comment 5

[Miko Mynttinen]

Attachment: testcase.html

Comment 6

[Botond Ballo [:botond]]

It appears that on this page, the size of the animated element is fluctuating between being above vs. below the pre-render threshold.

That is, when the animation is close to the 1.0 scale, the element is below the threshold (since the thresold is a little bit larger than the browser window size). When the animation is close to the 1.5 scale, the element is above the threshold.

The bug seems to occur when we are above the threshold and choose not to pre-render, suggesting that the issue is in the main-thread codepath, not the compositor codepath.

Comment 7

[Miko Mynttinen]

Attachment: Bug 1509272 - Always use new transform display items r=mattwoodrow

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/9e7fe63b341a
Always use new transform display items r=mattwoodrow

Comment 9

[Cristina Coroiu [:ccoroiu]]

https://hg.mozilla.org/mozilla-central/rev/9e7fe63b341a