"Reset" panning?

[dobedidoo]

Hi,

I use both QwtPlotZoomer and QwtPlotPanner - both working very well.

What I've noticed is that, if I do zooning, it is easy to "return"/reset to the default view using the QwtEventPattern::MouseSelect2, but I cannot find any corresponding "reset" of panning. If I have zoomed in or out and then done panning, then the QwtEventPattern::MouseSelect2 works well (it will "reset" both zooming and panning). However, if I only do panning (stay at default zoom level), then I don't know of any simple way to reset to default panning/view except if I first do zooming. Is there any kind of "one-click" reset of panning I could use which I have not found?

[Uwe]

No QwtPlotPanner does not store any type of history, where you can jump back and forth.

HTH,
Uwe

[d_stranz]

No QwtPlotPanner does not store any type of history, where you can jump back and forth.

Is there any feedback (signal or event) containing the new extents after a pan or zoom has occurred that would let one implement a stack to keep track of this history?

What is the response in QwtPlotZoomer / QwtPlotPanner to a single click without mouse movement? I use this in my own graphics scenes to implement a "zoom / pan to previous level" (i.e. pop the history stack) action.

[dobedidoo]

OK, I see. But I guess it should be possible to create eg. a function or method to trigger the same thing as is done when resetting the zoom? For example, a method that zooms in one "step", and then call "reset zoom" (corresponding to QwtEventPattern::MouseSelect2), which obviously seems to work. I guess that should reset to the default axes limits, even if I have panned but not zoomed. Or is there something I'm missing?

[dobedidoo]

Maybe I shall put the question like this: Is there any way to set the axis scales to the "default" (the same scale/limits as is initially set when I first plot/show the graph) - before I do any zooming and/or panning at all?

[Uwe]

https://qwt.sourceforge.io/class_qwt...87971a37716777

Uwe