Syntax:
clipbox[baseline](lower_left)(upper_right) clipbox[baseline]
This causes pspicture*
to take the place of the
pspicture
environment in the output file, so the drawing is
clipped by Postscript to the box described by the two points that
follow. This is a point list, so affine math is not allowed, but you
can make point references to definitions before the global
block, where math is of course fine.
The optional baseline is, if present, copied as-is to the
pspicture*
environment in the output.