Bug 81040 - mousewheel event wheelDeltaY data shows anomalies and jitter
Summary: mousewheel event wheelDeltaY data shows anomalies and jitter
Status: UNCONFIRMED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Event Handling (show other bugs)
Version: 528+ (Nightly build)
Hardware: Macintosh Intel OS X 10.7
: P3 Normal
Assignee: Nobody
URL: https://github.com/njx/mousewheel-test
Keywords:
Depends on:
Blocks:
 
Reported: 2012-03-13 15:02 PDT by Jason San Jose
Modified: 2012-03-22 15:19 PDT (History)
5 users (show)

See Also:

Attachments
Graph of mousewheel event wheelDeltaY on a MacBook Air running 10.7.3 Lion (56.98 KB, image/jpeg)
2012-03-13 15:03 PDT, Jason San Jose 		no flags Details
Archive of test project from https://github.com/njx/mousewheel-test (34.23 KB, application/zip)
2012-03-13 15:03 PDT, Jason San Jose 		no flags Details
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Description Jason San Jose 2012-03-13 15:02:11 PDT 
Steps to reproduce:
0. Requires a Mac with OSX 10.7 Lion for smooth trackpad scrolling (via laptop trackpad or external mouse/trackpad)
1. Download project from github (https://github.com/njx/mousewheel-test) or see attached zip
2. Open mousewheel-test.html
3. Follow instructions to perform a medium to large scroll
4. Observe output graph

The graph shows wheelDeltaY values for the duration of the "mousewheel". The attached sample graph shows large anomalies during acceleration and jittering towards the end of deceleration.
Comment 1 Jason San Jose 2012-03-13 15:03:05 PDT 
Created attachment 131718 [details]
Graph of mousewheel event wheelDeltaY on a MacBook Air running 10.7.3 Lion
Comment 2 Jason San Jose 2012-03-13 15:03:49 PDT 
Created attachment 131720 [details]
Archive of test project from https://github.com/njx/mousewheel-test
Comment 3 Alexey Proskuryakov 2012-03-13 16:54:03 PDT 
Are you seeing this with Safari 5.1.3?
Comment 4 Jason San Jose 2012-03-13 16:56:39 PDT 
Yes. Tested with Safari 5.1.4, Chrome 17.0.963.79 and Webkit nightly r110587.