Classic GUI and threading issue

[stef13013]

Hi,

As I can read, to do the right thing with QT and GUI threading, we have to :
1. Create a new thread (I already have my MainWindow)
2. Compute inside this thread all the "heavy stuff"
3. Then sending a signal to main gui thread (MainWindow) to do the all rendering/widget update.

Right, but I still don't understand how, in this same main thread, things will not freeze If I do important graphics updates

To give you an example :
In the Mandelbrot Qt sample, in the rendering function (updatePixMap()), if I insert a very time consuming code, all the main window still frozen !?

Is it possible to avoid this ?

Thanks.

[mvuori]

Yes: Don't insert a very time consuming code to the UI thread... Do it like in the example: create an image, doing time-consuming processing, as QImage in the worker thread and just splash that into place in the UI thread -- which is very fast.

[amleto]

I don't think we need to keep this one open...
http://www.qtcentre.org/threads/5034...hreading-issue