<AWT Dev> [9] Review request for 8166591 [macos 10.12] Trackpad scrolling of text on OS X 10.12 Sierra is very fast (Trackpad, Retina only)

[Semyon Sadetsky]

Looks good.

--Semyon


On 9/28/2016 8:16 PM, Alexander Scherbatiy wrote:
>
> Hello,
>
> Could you review the fix:
>   bug: https://bugs.openjdk.java.net/browse/JDK-8166591
>   webrev: http://cr.openjdk.java.net/~alexsch/8166591/webrev.02
>
>   This issue has been risen and investigated by JetBrains team in the 
> email:
> http://mail.openjdk.java.net/pipermail/awt-dev/2016-September/011991.html
>
>   MacOS Sierra 10.12 sends many scroll events with values close to 
> zero when the trackpad is used. The small scroll values are rounded to 
> +1 or -1 so one line scroll would be possible. It leads that many 
> small scroll events causes fast scrolling.
>
>   The proposed fix accumulates scroll values from the trackpad until 
> they exceed some threshold  values. Only after that 
> MouseWheelEvent.wheelRotation value is set. Mouse wheel scroll events 
> are handled as before, small values are just rounded to + or -1.
>
>   Thanks,
>   Alexandr.