1543224 - Don't accelerate zero-velocity flings into non-zero velocity flings

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect, P3)

Description

[Kartikaya Gupta (email:[e-mail])]

Spinoff from bug 1541644. While scrolling around on the wikipedia pastries table, I noticed that sometimes a vertical scroll attempt would result in horizontal scrolling instead. The lack of vertical scrolling is explained by bug 1541644 comment 6. And the seemingly-random horizontal scrolling was actually a result of fling acceleration. This happened because the previous scroll I did had produced some horizontal fling velocity, and then the new scroll, even though it had a zero horizontal scroll component, got accelerated into a non-zero horizontal fling.

I think it seems weird to accelerate flings with a zero horizontal velocity component into a nonzero horizontal velocity component, so I wrote a patch to eliminate that.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1543224 - Don't fling-accelerate a zero velocity to a nonzero velocity. r?botond

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1ef7a84a9533
Don't fling-accelerate a zero velocity to a nonzero velocity. r=botond

Comment 3

[Daniel Varga [:dvarga]]

https://hg.mozilla.org/mozilla-central/rev/1ef7a84a9533