qwt5.2 to qt6.0 : waterfall

[janK]

Hello

I has this waterfall running with qwt5.2.
Basically the code (per new line) was (within a derived class from qwtspectrogram):

WaterfallData = new SpectrogramData (plotData,
orig,
width,
Rastersize,
Displaysize,
amp);
this -> detach ();
this -> setData (WaterfallData);
this -> setDisplayMode (QwtPlotSpectrogram::ImageMode,
TRUE);
plotgrid -> setAxisScale (QwtPlot::xBottom,
orig,
orig + width);
plotgrid -> enableAxis (QwtPlot::xBottom);
Marker -> setXValue (marker);
this -> attach (plotgrid);
plotgrid -> replot();

with Spectrogramdata being derived from QwtRasterData.
Plotdata is a vector (array is you wish) containing the data to be printed.

Although exactly the same code worked nicely with qwt5.2, it does not work with qwt6.0. !!!!
No functions are called within the spectrogramdata (just added some print statements for verfication) such as initRaster, interval and value, while
- with the same parametervalues - when using 5.2 bith the Interval and the value functions from the (derived) Qwtrasterdata
is called many, many times.

So, my understanding of either QwtRasterdata, qwtspectrogram or qwtplot (the plotgrid used here) is failing and some semantic
changes occur between 5.2 and 6.0 within either qwtspectrogram or qwtplot. Note that I verified that the replot for the plotgrid (i.e. a QwtPlot)
is called regularly.
Any help would be greatly appreciated

best
jan

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