QwtPlot inside a QGraphicsView

[Uwe]

I wouldn't disable the backingstore completely - instead invalidate it manually ( QwtPlotCanvas::invalidateBackingstore() ) when you zoom in/out.

But I strongly recommend not using QGraphicsView: you will run into problems like yours and serious performance issues when zooming in deep. You can zoom in/out using QwtPlot in a better way and QwtPlotRenderer is much more powerful for creating vector graphics.

As long as there is no real strong reason for embedding a QwtPlot widget into a QGraphicsView: don't do it !

Uwe