1480369 - Parallax effect freezes scrolling with WebRender

Status: RESOLVED INACTIVE

(Core :: Graphics: WebRender, defect, P3)

Description

[David Heiberg [:dheiberg]]

It looks like WebRender has a problem with parallax scrolling effects, and if you scroll quickly, it will freeze/pause over the parallax area. I found this on http://www.originfeel.com/, when scrolling with inertia/quickly. I tried disabling WebRender and it scrolled smoothly, and also tried on Chrome and it also scrolled smoothly. 

Currently on nightly 63.0a1 (2018-08-01) (64-bit), with the 'gfx.webrender.all' config set to true.

Comment 1

[Markus Stange [:mstange]]

On macOS the pauses happen due to texture upload. The page uses these three images, which are all 2500x7500:

https://static1.squarespace.com/static/55c333fce4b031b2fa7bcc92/t/5a70f99c419202aab35671c9/1517353411867/Homepage+banner+1.jpg?format=2500w
https://static1.squarespace.com/static/55c333fce4b031b2fa7bcc92/t/5a70fa6824a6948f80296a52/1517353598928/Homepage+banner+2.jpg?format=2500w
https://static1.squarespace.com/static/55c333fce4b031b2fa7bcc92/t/5a70fadee2c48395a4eb65fe/1517353715356/Homepage+banner+3.jpg?format=2500w

So I think this is not a scrolling bug, but a texture upload performance issue.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

We should see how bad this is on Windows.

Comment 3

[Mayank Bansal]

smooth on my Win10x64+iGFX system at 720p screen res

Comment 4

[Mayank Bansal]

https://perfht.ml/2DMby7f

Comment 5

[Nicolas Silva [:nical]]

The original test case does not exist anymore and we have other bugs on file illustrating texture upload perf issues.