QTouchEvents capturing very slow.



  • Hi ,
    I am trying to implement multitouch in my application and catching events combining the techniques used n the fingerpaint and pinchzoom examples.
    Events are being captured and I am drawing in the scene but the points are being very scattered as you move the mouse fast. The effect I am getting can be seen "here":http://www.blikoon.com/?attachment_id=1655

    Is there anyting more I need to do to get the points drawn as they would in a normal mousemove event?Or am I just going a wrong way about this?

    Any help would be appreciated.



  • Hi,
    What you see is the effect of the sampling rate of the multitouch hardware. In some hardware drivers (e.g. PQ Labs and NextWindow), you can adjust the sampling rate. But even with a 120Hz sampling rate the scattering won't be eliminated for very fast movements. To hide the scattering effect you could always draw line segments between points instead of just drawing points.

    Kind regards,
    John



  • Thanks john_larring ,
    It seems that this is the only way around this.I try it and see the effect.


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