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GL accelerated javascript animations with QGraphicsWebView

  • Hi all,

    I am working on a project that needs to have an HTML5 transparent UI over a 3D rendering using Ogre3D engine.
    My solution was to use a QT 5.4's QGraphicsView with a QGLWidget as viewport to get an OpenGL context and to be able to render 3D things in QGraphicsScene drawBackground() method.
    I have added a transparent QGraphicsWebView in the QGraphicsScene and everything is working fine with a simple HTML5 UI.

    I have now tried to use a more complex HTML5 UI that makes a heavy use of javascript for animations.
    But i figured out that when there is a javascript animation running, my CPU use makes a huge peak and return to normal when the animation is terminated.
    I have then tried the same UI in a QGraphicsWebView that has not rendering acceleration, without QGLWidget as viewport, i have not anymore a such huge CPU usage peak.

    So does anyone have an idea why there is a such big javascript animation performance difference with and without OpenGL acceleration ?