[Qt-interest] Does QCoreApplication::processEvents() update timers?

[Karol Krizka]

Hi all,

I am using a third party 3D engine to draw a scene in a QGLWidget. The 
scene is quite big, so it takes a while to load, so I want to show some kind 
of an animation while it loads. However, the engine is not thread safe, so I 
cannot do the loading in one thread and drawing in another. What I would like 
to do instead is to redrew the scene after each major component has been 
loaded. It will be a bit choppy, but better than nothing.

I'm trying to accomplish this by having my drawing done inside a timer loop 
and call QApplication::processEvents(). Basically, I started a timer with 
QObject::startTimer() inside the QGLWidget and inside it I call updateGL(). 
I'm hoping that when I call processEvents(), it will call timerEvent() every 
while in order to trigger the redraw. However that does not happen. The 
timerEvent() is not called at all during the loading stage.

So my question is, does QApplication::processEvents() also update any 
running timers?

Also, since I need to start the loading stage after the widget has been 
shown. I cannot do it during QGLWidget::initializeGL(), because that is called 
before the widget is visible and so it will prevent the widget from being 
displayed. The same problem is by doing it inside QWidget::showEvent(), 
which is also called before the widget is visible. So I've decided to start 
the loading stage the first time the timerEvent() function is called. Could 
that be related to the problem I'm having?

--
Cheers,
Karol Krizka
http://www.krizka.net