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QtQuick 2 laggy?

  • Hello,

    I've tried the new qt 5.1 beta opengl msvs2012 together with the new desktop controls (I'm running on Windows 7 x64).

    When I run the "gallery" example under quick/controls I think its quite choppy when resizing the window, is this something that can be fixed?

    I've also tried to just create a QML document with only a textedit control with some text in and if you run it with QtQuick 1.1 (QMLViewer) the window resizing runs smooth but in QtQuick 2 (SceneGraph) its a bit laggy. My question is if this lagginess is restricted to window resizing and is nothing to care about?

    I also tried to add some SplitViewers together with some text edit controls inside and then it really starts to be choppy when resizing.
    When I do the same in WPF the window resizes smoothley, but I think QtQuick should be faster than WPF right?
    Maybe its just those controls that are a bit slow or it only slow when resizing, don't know.

    intel i7, 3 gHz, 16 gig RAM
    GeForce GTX 470 (latest drivers)


  • U are using a beta version , u should use the stable 5.0.2

  • A couple of notes here. There were some performance improvements regarding resizing going in after the beta so you might want to try again when the RC is out soon. If resizing performance is a major concern to you, you should probably not be using the opengl-builds on windows as they are not native to the windowing system and would cause some extra overhead there. The builds using angle will use direct 3d instead and might give you better performance particularly during resizing.

  • Thank you for the information, I'll try that when its released!

    Ok, do you know how performance is generally between the OpenGL build and Angle, which one perform better except when resizing the window on a Windows system?

  • I am afraid that I don't know the specifics. It could be depending on your graphics card, your drivers and the particular use case. We are setting up a wiki page here to help people decide between angle and opengl builds but performance is not something that has been added yet:

  • Ok thanks, I'll keep an eye there!

  • I tried the angle version of qmlscene and the resizing is now much smoother, thanks :)

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