[Gnuplot-info] scatter plots with circles when term = aqua

[Robert P. <rd...@gm...>]

I have a pair of datasets that I want to plot as scatter plots,
overlaid on the same graph.  I want dataset A to be plotted using 8
point solid gray circles and dataset B to be plotted using 12 point
solid red circles.   And my terminal is aqua.

So here's the rub: I cannot use 'with points' because aqua doesn't
have a solid circle in its symbol repertoire (at least, 'test' doesn't
show one).

I may be able to use 'with circles', but I don't see how to set the
point size. 'set style circle' would set the size for both datasets,
which isn't what I want.  I could add a third column to my datasets to
control the size, but then the size is in units of the x axis, and the
x axis scaling is automatically generated.

So: are there global variables that tell me the limits of the x axis
and the size of the plot?  If so, I could do something like:

 plot "-" using 1:2:(8*scaling) with circles lc rgb "#888888" \
         "-" using 1:2:(12*scaling) with circles lc rgb "#ff0000"

... or something like that.  Any pointers?  TIA.