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BB10 Dev Alpha Qt Quick animations are too slow



  • I wonder why QML animations in Qt Quick are so slow on Dev Alpha device? I checked both Qt 4.8 and Qt 5.0 (bundled with my app). Consider following simple example:

    @
    import QtQuick 1.1

    Rectangle {
    width: 728
    height: 1280
    color: "black"

    Rectangle {
        id: inner
        anchors.fill: parent
        color: "green"
    
        NumberAnimation { target: inner; property: "opacity"; duration: 2000; to: 0; running: true }
    }
    

    }
    @

    This is simple fullscreen green rectangle, which fades out slowly. On desktop it's smooth. On Nokia N9 it's smooth. On Symbian it's smooth. On Android it's smooth. On BB10 Dev Alpha it's lagging horribly.

    Take another example:

    @
    import QtQuick 1.1

    Rectangle {
    width: 728
    height: 1280
    color: "black"

    Rectangle {
        id: inner
        width: parent.width
        height: parent.height
        x: -width
        color: "green"
        NumberAnimation { target: inner; property: "x"; duration: 2000; to: 0; running: true }
    }
    

    }
    @

    This one is moving green rectangle slowly from left to the screen. Same story. Horrible lags on BB10. Does anyone else experience this? What's the problem? Will this be fixed in some later versions?



  • Unfortunately I don't have a BB10 developer device and I cannot try it myself. The virtual machine of BB10 that I installed on my Mac OS X was quite slow in general. I hope that BB10 on the final device that will be released on the market next year will be fast and smooth :)



  • You're not alone :) I'm having the same issues for a very long time already. Now that RC1 is out I've rechecked everything and reported a couple of bugs. I've used one of your examples, hope that's ok :)

    https://bugreports.qt-project.org/browse/QTBUG-28487
    https://bugreports.qt-project.org/browse/QTBUG-28488
    https://bugreports.qt-project.org/browse/QTBUG-28485
    https://bugreports.qt-project.org/browse/QTBUG-28486



  • Did you enable OpenGL?
    Which one of the dev alphas do you have?

    On my dev alpha animations are running ok.



  • How did you enable OpenGL? AFAIK it's enabled by default. I'm on a DevAlpha-A with Beta-4. The second example of the OP runns smooth, but too slow. It takes 5 seconds instead of 2 to complete the animation.



  • In Qt4 it is not enabled by default, in Qt5 only if you use QtQuick 2.

    setViewport(new QGLWidget);
    setViewportUpdateMode(QGraphicsView::FullViewportUpdate);



  • You're right thanks. Sorry I didn't mention that I'm using QtQuick 2.0 on Qt 5.0 RC1.



  • Seems like it could be fixed in the new device firmware. My initial tests seem to have much better performance.



  • I can second that. At least the simple animation now really takes 2 seconds and not 5 as before. Still need to test with more complex scenes...



  • Animations now have proper timing, but frame rates are still bad. I'm still stuck with max ~30 FPS. I've updated the bug report with some example BARs. Maybe someone with a DevAlpha-B could give it a try?!

    https://bugreports.qt-project.org/browse/QTBUG-28487


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