In order to reduce the size of postscript files, the gray value and not all
three calculated r,g,b values are written to the file. Therefore the
analytical formulae are coded directly in the postscript language as a header
just before the pm3d drawing, see /g and /cF definitions. Usually, it makes
sense to write therein definitions of only the 3 formulae used. But for
multiplot or any other reason you may want to manually edit the
transformations directly in the postscript file. This is the default option
nops_allcF. Using the option ps_allcF writes postscript definitions of
all formulae. This you may find interesting if you want to edit the
postscript file in order to have different palettes for different surfaces
in one graph. Well, you can achieve this functionality by multiplot with
fixed origin and size.
If you are writing a pm3d surface to a postscript file, it may be possible to
reduce the file size by up to 50% by the enclosed awk script
pm3dCompress.awk. If the data lies on a rectangular grid, even greater
compression may be possible using the script pm3dConvertToImage.awk.
Usage:
awk -f pm3dCompress.awk thefile.ps >smallerfile.ps
awk -f pm3dConvertToImage.awk thefile.ps >smallerfile.ps
