[Qt-interest] QPainter: It is not safe to use drawPixmap() outside the GUI thread

[R. Reucher]

On Wed, 28 Oct 2009 14:36:59 +0300, Serge wrote:
> I have QT application, which renders SVG on QPixmap in a separate
> thread. Separate thread is needed because rendering takes a lot of time.
> this application was developed in QT 4.3.3 it worked fine without
> warnings.
> 
> now i built it in QT 4.5.2
> when it works in debug output window i can see a lot of messages:
> QPainter: It is not safe to use drawPixmap() outside the GUI thread
> 
> Is it critical warning?
Yes (well, it depends).

> Can i leave rendering the same or i need to rewrite rendering so that it
> would not use QPixmap? What thread-safe alternative of using QPixmap?
Use a QImage instead.

HTH, René
-- 
René Reucher
rene.reucher at batcom-it.net
http://www.batcom-it.net/