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john_k
31st July 2014, 18:48
Has anyone implemented a rubber band zoom on the qwtpolar spectrogram example?
The QwtPolarPicker has a setRubberBand method but when I set it to RectRubberBand
in the polarpicker I get nothing.

Thanks

Uwe
2nd August 2014, 10:53
The QwtPolarPicker has a setRubberBand method but when I set it to RectRubberBand in the polarpicker I get nothing.

For zooming you can use a combination of QwtPolarMagnifier and QwtPolarPanner, but there is no rubber band zooming implemented so far. If you want to do so you can start with a picker initialized like this:


picker->setStateMachine( new QwtPickerDragRectMachine() );
picker->setRubberBand( QwtPicker::RectRubberBand );The "borderPath" warnings can be ignored - nevertheless I added a check in qwt_widget_overlay.cpp ( trunk + 6.1 branch ) to avoid them.

Uwe