clarification of selectregion / te_selectRegion

[equilet]

We need to document the specifics of selectregion. Can you please elaborate on the way this works?

It looks like te_processargs() fills variables like rangelen, numfunctions, controlpoints, etc., then attempts to draw a selection box with this information (which doesn't seem to include information about frequency, although I did notice sel_box and freq_max/freq_min). I am unable to tell whether or not this function is operative, because I haven't been able to successfully get a rectangle to draw based on the arguments to selectregion.

[equilet]

a description of dumpbeats would also be useful, and most likely looks similar w/r/t the args processor