On 04/24/2012 04:35 PM, bootchk wrote: > Thanks. How I interpret your last comment is: it is in Ubuntu but not > upstream to Qt (whoever that is now, Nokia or other.) As long as I use > Ubuntu's version of Qt (whether the source or libraries) it should work.
Correct. > Also, referring to: https://wiki.ubuntu.com/Multitouch , specifically > where it says "2 finger gestures require extra setup". I interpret that > to mean: without the setup, the synaptics driver (which is > inappropriately named, is really THE driver for most touch HID's, not > just those of the Synaptics brand) will hide all one finger and two > finger events from further up the stack, i.e. from a Qt application? > Possibly that is the problem with my testing. It could be. And then three and four finger interactions are grabbed by Unity. You have to put five or more fingers down on a trackpad to start sending events that aren't caught by Unity or X synaptics. > The whole business of the stack confuses me. My understanding is a > driver can translate certain sequences of touch events into single > "mouse" events, i.e. recognize multi-finger gestures, in an attempt to > be "friendly" to an app. For example, two finger tap in a certain > corner translates to something, as you can see in the System Settings > panel for a touchpad. For example, the way you must write an app to be > "pen-friendly" is to rely on the translated mouse events instead of raw > pen events. How does an application control what the driver does, if > the application wants raw touch events to do its own gesture > recognition? E.g. using Qt custom QGestureRecognizer. Does Qt have > any way of knowing that certain "friendly" mouse events were in fact a > sequence of touch events translated by a driver? (Not that it needs to, > what could Qt or an app do differently if it knew, besides tell the user > that the driver might be improperly "setup" for the gestures that Qt or > the app was ready to recognize.) You're getting at the fundamental problem of the traditional touchpad "gestures" being interpreted in the X server. It worked reasonably well to this point, but is fundamentally broken now. We need to rework how touchpad gestures are recognized. They should be moved into the toolkits. However, that's a large amount of work. We are looking into our options. > Does Qt QPanGesture require a certain number of fingers, or even require > touch at all? For example, would Qt recognize a pan consisting of > "mouse" events that were in fact translated from touch events by a > touchpad driver? The Qt gestures only work with touch events, as far as I know. They will not work with mouse events. > If there is a better forum for this discussion, please let me know. Feel free to ask questions and participate in discussions on the multi-touch-dev mailing list. You can subscribe on the project's page: http://launchpad.net/~multi-touch-dev -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xf86-input-wacom in Ubuntu. https://bugs.launchpad.net/bugs/901630 Title: multitouch + qt doesn't work (eg fingerpaint demo) with wacom serial touchscreen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xf86-input-wacom/+bug/901630/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
