#ident	"@(#)roff:troff.d/devi10/README	2.5"
This directory contains source for the troff postprocessor
for the Imagen Imprint-10 laser printer.  It also contains
the source for the font tables and DESC file for that device.

There are also programs that can be used with printers that accept Impress,
whether they were made by Imagen or not.

----------------------------------------


You may have some changes to make to the source code I've supplied. Most
of them will have to be made in files init.h or dimpress.h. I'll
list the more obvious ones, although there undoubtedly are some I've forgotten.
As set up now, devi10.mk will create "di10" to generate input for the
Imagen Imprint-10 in a way completely compatible to the di10 in DWB 1.0.


FILE init.h

    FONTDIR	- Needs to be defined as the normal troff font directory
		  on your system. I've set it to "/usr/lib/font" which is
		  probably correct for your system. The font directory can
		  be set at run time (in dimpress and troff) using the -F
		  option.

    BITDIR	- Directory for Imagen-style raster files
		  ("/usr/lib/raster"). The post-processor (dimpress) will
		  look for new raster files for device "xxx" in directory
		  rastxxx located in BITDIR. The -B option can be used to
		  do run time setting of *bitdir.

    OLDBITDIR	- The is the directory where you'll find the old Imprint-10
		  raster file directory rasti10.  (/usr/lib/font/devi10)

    IPR		- Full pathname for the ipr program on your system. I've set
		  it to "/usr/bin/ipr" but that might not be right for you.
		  If you're not running Imagen's spooling package you don't
		  have to worry about this guy - just make sure you always
		  call dimpress with the -t option.


FILE dimpress.h

    PR_INIT	- This defines the default values to use with the printers
		  that are directly supported by dimpress. If you want to
		  add a new printer just make up an appropriate line (look
		  at the definition of Prdata) and add it to PR_INIT. The
		  list must be terminated by an entry that has NULL defined
		  for the value of prname, so make sure you don't put anything
		  after the current last line. You also may not agree with
		  some of the default values I've picked for the different
		  printers. If you don't, change them in PR_INIT before you
		  compile dimpress.

		  The only difference between i240 and i10 is that when you
		  use -Ti10 dimpress looks in OLDBITDIR for a raster directory
		  called rasti10, while with -Ti240 it looks in BITDIR for
		  rasti240. The -Ti10 option should be used to run Imprint-10s
		  using the old raster files. That's the only option you'll
		  need to use if you've got OLDBITDIR defined properly.
		N.B.  this is the default setup, as distributed.

    PR_NUM	- In dimpress.c pr_num refers to the line in PR_INIT (actually
		  the index in prdata[]) that will be used as the default
		  printer.
----------------------------------------


The programs included in this directory are:


    dimpress.c	troff post-processor that generates version 2.0 Impress
		commands. Code came from di10.c (originally dcan.c) and has
		been extensively modified. It can now generate output using
		raster files in either the old (versetec) or new (Imagen's)
		format. Reasonable output will be produced on any printers
		that accept Impress, independent of the resolution of the
		raster files being used.  Creates an output file in /tmp/dimpa*
		and calls ipr to put its output in spool directory.
		ipr and its subsidiary programs are supplied by Imagen.

		The known printers are i300, i240, i480, and i10. i10 and
		i240 are really the same printers, except that i10 assumes
		everything is being run the old way (like di10). In other
		words the raster files are the old format and they're hidden
		away in the font directory. The i240 really just assumes the
		raster files are in *bitdir/rast240.

		The drawing routines have also been rewritten to take
		advantage of graphics primitives available in Impress. You
		should be able to use them if you're running 1.9 or any
		newer versions. The new routines are in file impdraw.c
		and you may use that by redefining $(DRAW) in devi10.mk.
		If you've got an older printer that doesn't
		support the graphics commands let the makefile use
		draw.c instead.

		A file called RASTDATA defines the format and resolution of
		the raster files. dimpress expects to find it wherever it's
		reading raster files. If the file can't be read dimpress
		(routine rastsetup()) assumes the raster files are the old
		format and 240 dpi resolution. It really should be an error
		but RASTDATA is new and won't be part of the old raster file
		directory unless you add it.

		Right now RASTDATA can include two commands that are
		understood by routine rastsetup(). The first is the string
		"format" which should be followed by either "old" or "rst".
		The second string is "resolution" which is followed by a
		number that specifies the raster file resolution. Everything
		else is skipped.


    makei10	Builds ASCII font and device files for other typesetters,
		like the APS-5, that can be used by dimpress when it's
		trying to print files using the new raster files. The
		real problem here is that dimpress (in routine put1())
		assumes that the code field in the font files it's using
		is also the glyph number for the character in any raster
		files that are being used. That's obviously not true unless
		the raster files and the font files were generated together,
		If dimpress used the normal
		APS-5 files from /usr/lib/font/devaps you'd be guaranteed
		to get garbage.

		Obviously there are a bunch of different ways to get around
		the mapping problem. I chose to hide extra font files, built
		from the APS-5 and i300 files, in the raster file directory.
		When dimpress tries to process a troff output file that
		was generated for printing on device 'xxx' it first looks
		for a devxxx directory in the raster file directory and
		if it doesn't find it there then it uses the normal devxxx
		directory in /usr/lib/font.

		makei10 reads the binary '.out' files for the 202 or i10,
		and the ASCII font and device files for the APS, and writes a new
		set of ASCII files for the APS into a directory called
		devaps in the directory with the raster files.  makei10
		expects to find the ASCII font files for the APS in
		directory devaps below the parent of the working directory.
		Only "di10" will read the new set of font tables for the APS.
		Troff will still use the files in the original devaps directory.
		Once you've run 'makei10' you'll still have to run
		makedev before 'di10' will be happy.
		Was written with tabs set to every fourth column, so
		things will look a little funny unless your tabs are
		set the same way.
	
		N.B.  It is not necessary to run this program if you are
		content with the distributed set of font files in 
		devi10/rasti10/devaps.


    readrast	Simple program that reads raster files in Imagen's Rst
		format and dumps bitmap and other glyph information to
		stdout in ASCII. Individual glyphs can be selected using
		the -o option. If none are selected all the glyphs in each
		of the input files will be displayed (and that can take a
		long time).

		Example: readrast -o1,5,7-10 R.8 I.14


    printrast	Another simple program that reads raster files in Imagen's
		format and writes Impress commands needed to display glyph
		bitmaps and other info on an Imagen printer. Output goes
		to stdout. A simple document header is prepended to the file
		if the -H option is used. The resolution of the printer we
		want to use to print the file should be specified using the
		-r option. Raster files are all assumed to be in the current
		directory (actually ".").

		Example: printrast -H -r300 R.10 I.10 B.10 CW.18 >xxx


    buildrast	A fairly involved program that reads an ASCII control file
		and raster files supplied directly from Imagen (Rst format
		and Tex character set) and builds raster and font files that
		that troff and dimpress use.

		Individual fonts or sizes can be selected using the -f and
		-s options respectively. If neither is used all the fonts in
		all the point sizes listed in RASTi300 (or whatever file is
		the argument) will be built. troff's ASCII files are only
		built when the current size that buildrast is working on is
		equal to the unitwidth value set in RASTi300. The DESC file
		is built at the end after all the raster files have been
		finished.

		In the example below the original raster files are assumed
		to be in the current directory. All the new stuff will be
		put in directories ./devi300 and ./rasti300. If you're keeping
		Imagen's raster files somewhere else, which might not be
		all that unusual because they take up at least 17,000
		blocks, use the '-S dir' option to set the directory.

		Example: buildrast RASTi300



You'll probably only need to compile dimpress and makedev unless you want
to play around with the raster files.


----------------------------------------


In most cases dimpress can replace di10, although there are a few
differences in the way the options are handled. The important changes are,


 1: The -x and -y options set offsets in inches rather than pixels, as was
    the case in di10.

 2: The -f option used to set the raster table directory has been changed to
    -B. For the time being -f will be supported in dimpress but its use isn't
    recommended.

 3: The -e, -b, -B, -h, -H, -L, and -S options in di10 have been removed.

