>From the attachment you can see that mir giving a bogus event stream. When you lay two fingers on the screen at roughly the same time (like when doing a pinch gesture) it's common for mir to not generate or send the "down" event for the first touch point.
qtmir has a basic event stream sanity check and validation. It detects this problem and transforms the action=change for the first touch event with id=0 into a action=down instead. But then we end up with an input event with *two* pressed touch points, which at least makes sense but I think Qt does not like that. It probably expects a single touch up/down per event, like android. I could make qtmir's event stream validator more sophisticated and have it split those two touch down actions into two separate input events, but mir should really send us a clean event stream in the first place. ** Attachment added: "Typical qtmir log output on an unsuccessful pinch gesture" https://bugs.launchpad.net/ubuntu/+source/qtmir/+bug/1531517/+attachment/4545169/+files/qtmir-mir-input.log ** Also affects: mir (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to mir in Ubuntu. https://bugs.launchpad.net/bugs/1531517 Title: pinch to zoom not working reliably Status in Canonical System Image: Confirmed Status in mir package in Ubuntu: New Status in qtmir package in Ubuntu: Won't Fix Bug description: in the last few days (using rc-proposed 221 on krillin) pinch to zoom gestures do not work reliably anymore. Appears to be system wide as there have been reports in the follow apps that all use PinchArea from QML: - Camera: pinch to zoom in viewfinder stops working, pinch to zoom in Photo Roll to zoom a photo stops working - Gallery: open a photo and pinch to zoom doesn't work - Webbrowser: pinch to zoom on a web page not working Could be mir/qtmir related To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1531517/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
