Histograms with fill solid and monochrome Postscript

[Philipp K. J. <ja...@ie...>]

Let's say I am trying to generate histograms
like this:

set style fill solid
set style histogram clustered
set style data histogram
plot "data" u 1, "" u 2, "" u 3

I get a plot of histograms, with each "bin"
in a different color (red, green, blue).

Now, I would like to export this to a monochrome
Postscript terminal. I would expect that the colors
are mapped to different levels of grayscale.

Instead, all colors seem to be mapped to black
(or very nearly black).

Is there a way to achieve the kind of automatic
color-to-grayscale mapping I envision, or is this
currently not supported?

Best,

		Ph.