Scrolling on twitch.tv flashes white before revealing content. |
||||
Issue descriptionChrome Version: 59.0.3071.113 OS: Chrome What steps will reproduce the problem? On high DPI device: (1) Visit twitch.tv with a stream playing (currently SGDQ 2017) (2) Scroll up or down quickly. What is the expected result? Expect a smooth composited scroll. What happens instead? Instead, the revealed area is white momentarily before being revealed. It seems as though it's not rastering any offscreen content in the composited scroller even though the entire scrolling contents shows up in the layers panel. There is no flashes with paint flashing so the scrolled content is not repainting. Please use labels and text to provide additional information. For graphics-related bugs, please copy/paste the contents of the about:gpu page at the end of this report.
,
Jul 7 2017
I can't reproduce on linux Version 59.0.3071.115 (Official Build) (64-bit)
,
Jul 7 2017
Interestingly I can reproduce on Linux 61.0.3141.7 (Official Build) dev (64-bit). The difference there seems to be that on Low DPI Linux the entire page repaints on scroll whereas on dev the scroll is composited.
,
Jul 7 2017
I can reproduce on TOT with --enable-prefer-compositing-to-lcd-text on Linux. Not without it.
,
Jul 7 2017
,
Jul 7 2017
Just trying to check if we appended any checkerboarded tiles in a frame (https://cs.chromium.org/chromium/src/cc/layers/picture_layer_impl.cc?q=picture_layer_impl.cc&dr&l=397), I don't see any with or without --enable-prefer-compositing-to-lcd-text. It does feel like there is a white flash when scrolling up, but I didn't see a difference with the compositing to lcd text flag.
,
Jul 10 2017
I artificially throttled the main frames and could clearly see the white area before seeing content with --enable-prefer-compositing-to-lcd-text. Its definitely not checkerboarding, the commits that fix it don't even come with any new painted content or raster work. Looks like the layer is being clipped incorrectly and an update from the main thread fixes it. I thought it could be something that the page was doing, without the compositing flag we defer to main thread scrolling so the page would get to synchronously respond to the scroll event. I tried removing all scroll listeners on the page from devtools but that didn't change anything. Could also be some Layer positioning change that blink makes after the scroll but is not replicated correctly on the impl side. cc-ing folks more familiar with that.
,
Aug 10 2017
I am also seeing this on https://www.amazon.com/alexa-skills/b/ref=skillsrw_surl?ie=UTF8&node=13727921011 : use --enable-prefer-compositing-to-lcd-text and enable mobile emulation and scroll the skills carousels horizontally. This reproduces back to 52.0.2727.0 (I didn't go further). |
||||
►
Sign in to add a comment |
||||
Comment 1 by enne@chromium.org
, Jul 7 2017