Z-buffer magic

[Loki Jorgenson Rm421]

	I have just read the little blurb in the last issue of Pipeline
(SGI news letter) which described alternate uses for the Z-buffer.  We
were wondering if anyone has attempted to use the Z-buffer in terms of
some sort of ray-tracing mechanism..... OUTSIDE OF A GRAPHICAL SENSE.

	We run computer simulations of particle aggregation on growing
surfaces.  One of the studies that we are currently conducting is to
examine the effect of varying the angle of incoming particles on an
aggregating surface.  It seems quite possible to take the tremendous
power of the Z-buffer hardware to run this simulation for us.

	The surface would become a series of objects, the incoming particle
would come from the "point of view", the point of attachment would be the
closest point to the eye.  However, it is not obvious that this sort of 
control is possible from a programming stand-point (ie, no graphics involved)
or that one can use these purported techniques in the 4D/xxG harware
(as opposed to GT/GTX).  Can anyone comment?

Thanks,
                             __          __
Loki Jorgenson              / /          \ \  node:  loki at Physics.McGill.CA
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