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[SOLVED]Issue with particle system and hanging window

  • With the downloaded Qt5.0.2 - msvc2012_64 on win7 when I try to move the window of the following qmlscene, the window keeps hanging at its current position and doesn't react anymore until changing the focus with alt+tab.

    import QtQuick 2.0
    import QtQuick.Particles 2.0

    Rectangle {
    width: 224
    height: 288
    color: "black"
    id: background

    ParticleSystem {
        anchors.fill: parent
        ImageParticle {
            source: "star.png"
            colorVariation: 1.0
        Emitter {
            width: background.width;
            height: 1
            size: 8
            sizeVariation: 5
            lifeSpan: 6000
            velocity: AngleDirection {
                angle: 90
                angleVariation: 1
                magnitude: 150
                magnitudeVariation: 100


    Without the particle system I can move the window around. I already recognized this behavior in 5.0 but I thought this would be fixed in an upcoming version.

  • There is a rather ugly issue with timers starving system events when you combine msvc 2012 with win7. In Qt 5.1 there is a new renderloop for Qt Quick for windows which, amongst other things, avoids this particular issue.

  • Thanks for your reply, so I'm looking forward to Qt 5.1.

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