[ REQ 5359]: PS Snapshot bug (no z buffer?)

[sullivan at GANG.UMass.EDU]

I loaded the geomview file "tetr" to make a postscript file of a tetrahedron.
Saving it with PS Snapshot produced the file below, which draws the faces
in the wrong order.  It is easy enough in this case to reorder the file by
hand, and I guess I understand that the algorithm is probably just ordering
faces by the z positions of their centers.  It is too much to ask PS Snapshot
to do everything right for intersecting faces.  But in cases like this, where
two faces _share an edge_ it is easy enough to do the really correct ordering.

-John

-------------------------------------------------------------------------------
%!PS-Adobe-2.0 EPSF-1.2
%%Title: PSSnapshot
%%Creator: pssnap.c
%%CreationDate: Thu Apr 20 10:32:07 1995
%%For: sullivan
%%Pages: 0 1
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