In the following trivial 3D gnuplot scatter graph, there are two points (labeled A and B). Unfortunately, since this there is no logical connection between the points, it's impossible to tell visually where these points lie in the 3D space.

The way I would prefer to remedy this is to add vertical lines on the Z axis down to the Z = 0 floor plane, something like the following blue lines (color irrelevant) which I slapped on with MS Paint to illustrate what I want:

This way it's easy to see, for example, that A is higher than B. After some searching, I haven't been able to dig up anything on how to implement this with gnuplot. I would greatly appreciate any assistance whether it's an RTFM pointer, or existing example of how to implement this type of plot.
