GL accelerated javascript animations with QGraphicsWebView

[Harold]

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 ?

Regards,
Harold