Bug 194996 - Scrolling tree should do an update after layer flushing on macOS
Summary: Scrolling tree should do an update after layer flushing on macOS
Status: RESOLVED DUPLICATE of bug 195507
Alias: None
Product: WebKit
Classification: Unclassified
Component: Scrolling (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2019-02-24 21:32 PST by Simon Fraser (smfr)
Modified: 2019-03-12 20:04 PDT (History)
3 users (show)

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Description Simon Fraser (smfr) 2019-02-24 21:32:14 PST 
The scrolling tree contains the latest scrolling-related state for layers managed by the scrolling tree. When the main thread flushes compositing layers, it might flush layer positions that are stale in relation to the scrolling thread state. We currently (mostly) avoid jank here by the tricky "set or sync" logic, and "isInUserScroll" state, but it would be simpler to just have the scrolling tree do a pass after layer flushing.
Comment 1 Simon Fraser (smfr) 2019-02-24 21:33:01 PST 
On iOS we already do this by pushing the current layoutViewportRect through the scrolling coordinator in the UI process, after receiving a transaction.
Comment 2 Simon Fraser (smfr) 2019-03-12 20:04:27 PDT 

*** This bug has been marked as a duplicate of bug 195507 ***