QwtPlotMagnifier zooming around the mouse pointer

[Uwe]

Such a mode is not implemented, but isn't very hard to implement. You could derive from QwtPlotMagnifier overloading the following 2 methods:

widgetWheelEvent to store the mouse position
rescale, where you implement zooming around the mouse poistion

Starting with the code from QwtPlotMagnifier ::rescale should help.

Uwe

[cesroc]

Hello Uwe,

Thanks a lot. I found a different way of doing. I install an event filter in my axis and I handle the wheel event.
It works fine for a normal zooming in and out, but I didn't find the right calculation to have it around the mouse pointer.
I have the mouse position and everything I need but I didn't figure out yet how to calculate to have the zoom around the pointer.
Can you help me on that? Do you have an example?

Thanks in advance.
Best Regards.

[Uwe]

Using the maps from QwtPlot::canvasMap() you can translate between widget ( canvas ) and plot coordinates.

Uwe

Using the maps from QwtPlot::canvasMap() you can translate between widget ( canvas ) and plot coordinates.

Uwe