Hey,

I want to create an updating plot very similar to the oscilloscope example provided with the latest qwt. I'm trying to follow through the source code for the example but I'm a bit lost with QwtSeriesData, and its many subclasses. My application has a couple of threads. A child thread pushes (x,y) data at a fairly high frequency through signals to the parent (gui) thread. The entire series of data sent over the duration of the program needs to be available so I have the child thread signal only the latest data, which is appended to (x,y) vectors in the main thread.

To plot the data, I tried following bits of the oscilloscope example. Instead of having a timer invoke QwtPlotDirectPainter, I have it setup so the incoming signal with the new (x,y) data will do it. But I'm stuck with which data points object to store my data in and pass over to the QwtPlotCurve object. I have two C++ lib vectors storing the data right now (and they keep increasing in size).

Also one more quick question -- what exactly does the 'attach' function call do for a lot of the classes in the example? ie. create plot, create grid/attach to plot, create curve/attach to plot, etc.

Thanks,
kif