
Here are better programs for converting the raytracing stuff to
black and white levels suitable for printing on a laser printer.
The following two programs produce a halftone image of the ray
tracing, formatted as a bitmap for sending to IMAGEN printers.
The code is based on the stuff that Steve Hawley kindly posted
to the net, but I found the masks Steve used for his MAC didn't
look very good at higher resolutions.  I developed a mask of
my own that works reasonably well (although DDL's is better, but
I can't post that).

The programs work with raytrace version 2.0 -- they take the size
of the pixel map from the input file.  If you don't have version2.0
running, you can fix this by the following hack to the output:
	echo "451 451" > foo.tmp
	cat foo.tmp data.dis > data2-0.dis
	rayht data2-0.dis > foo.imp

The first program, rayhtimp.c, generates an IMPRESS bitmap.  The
second program generates a raster scan suitable for the IMAGEN
BITARRAY emulator that exists on ImageServer products running
software at or beyond V2.2.  The bitarray-producing code could
easily be modified for other file formats.  (For those Imagen
owners who don't know about it, bitarray is a very limited but
fast emulator that allows bitmaps which are aligned to multiples
of 32 pixels to be transmitted to the printer without the overhead
of impress and without needing to translate to the more cumbersome
impress format for bitmaps.  Bitarray is most useful on printers
with communications options that operate faster than 70 kilobits/s
(TCP, XNS, parallel).  Otherwise, impress is about as fast, because
communications becomes the bottleneck.  I am informed that the
ImageStation products (whose parallel is slow, anyway) don't
support bitarray.)

