1636982 - Interleaving rotation and pinch gestures on macOS probably doesn't work properly with apz.allow_zooming enabled

Status: RESOLVED FIXED

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

Description

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

So there's a comment here that implies the macOS widget should lock into either rotate or magnify gestures when the OS sends us interleaved events. This machinery involves setting the mGestureState variable properly, which doesn't happen in the apz_allow_zooming branch of magnifyWithEvent here. So I suspect that if you turn on apz.allow_zooming and do a trackpad gesture that's pinch+rotation, the content will get both effects instead of just one.

However, the rotation implementation is currently broken, and has been since e10s happened (see bug 1108553) so I couldn't actually test this theory. Also, as long as rotation remains broken, this doesn't matter. However, the changes I'm making for bug 1636473 make it harder to fix this problem (by deleting relevant code), so I'd rather fix it before making my changes for bug 1636473.

Comment 1

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

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #0)

so I'd rather fix it before making my changes for bug 1636473.

Actually building the patches in that order turns out to be pretty involved. It's simpler to just fix this after.

Comment 2

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

Attachment: Bug 1636982 - Restore old behaviour of disallowing interleaved rotate and magnify gestures on macOS. r?tnikkel

Depends on D74640

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/31a4d6dfb08f
Restore old behaviour of disallowing interleaved rotate and magnify gestures on macOS. r=tnikkel

Comment 4

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/31a4d6dfb08f