Adding markers to oscilloscope example

Hi All,

I would like to display markers at peak value of sine curve, in the oscilloscope example. I have tried to add marker points (x,y values of markers) in the Plot::updateCurve() method.

Also, I have tried setting marker values using d_origin object (QwtPlotMarker) inside the Plot::updateCurve() but it does not work. The marker is displayed after the replot function is called whereas I want it to be displayed in continuous fashion, just like curve.

Cheers.

P.S: Newbie alert. It has took me couple of weeks to understand a wee bit of the example. Any assistance will be appreciated.