PROGRAM	RASTER
C
C	This is the root section of the general purpose raster generation
C	program.  One or several input files, containing coded vector lists,
C	are entered, and each file may be scaled and offsetted and then
C	plotted on one many vector oriented devices or raster oriented
C	devices.
C
C	For more information on this program's use, see the HELP files.
C	For more info on the raster generation, see RASGEN, the 
C	rasterization (is that a word?) subroutine (its commented to death).
C	For information on the device independant graphics routines used at
C	Michigan State University, see the subroutine VECTOR, part of the
C	MSULIB library (RASGEN also describes the calls from VECTOR).
C
C	This package was written with the intention that adding new printers
C	would be a fairly easy task.  The user interface (subroutine INPUT)
C	should set up the device number, and RASTER will call the added driver
C	subroutine.  See the existing driver subroutines - they are very much the
C	same, letting RASGEN do all the hard work.  New printers will require
C	a subroutine to pack the raster data into print buffers, after which
C	it is a simple matter to send the print buffer to the printer.
C
C	All vectors received by RASGEN are assumed to be in inches, with the
C	origin in the lower left corner of the paper.  The width of the paper
C	is the Y axis (11-12 inches, depending on the printer) and the long axis
C	of the paper is the X coordinate.  This allows an almost infinate length
C	graph (limited by problems with integers - ie 32767 divided by the 
C	nibs/inch in the X direction.  For the Printronix (72 nibs/inch in X),
C	the maximum length of paper is 32767 / 72 = ~455 inches.  Long enough.)
C
C	The raster buffer actually comes in two parts - a series of pointers
C	and the buffer itself.  The buffer is orginized so that the low bit of
C	the first byte is the (0,0) bit in that band or window.  The most
C	significant bit of the first byte is the eighth bit from the edge of the
C	paper.  The low bit of the second byte will be the nineth bit, and so on.
C	So one row of dots is described by a series of bytes, and the next row
C	by another series, etc.  Each series of bytes is pointed to by a pointer
C	from the first part of the common region.  This pointer is an X offset
C	into the buffer, to find the line of dots we need to operate on.
C
C	PAPER LAYOUT:
C
C	==========================================================================
C (0,11).								(n,11) .
C
C
C
C
C  ^
C  |
C  Y
C
C
C
C
C (0,0)	. 					X-->			(n,0) .
C	==========================================================================
C	|			|			|			|
C	raster band or window 1		   #2			    #3	       etc
C
C
C
C	Overlay tree:
C
C			|-------INIT-INPUT-VECTOR
C			|
C			|
C			|				|------RASGEN
C			|-------IDS (driver program)----|
C			|	IDSRAS (raster buffer)	|------IDSOUT (output)
C	RASTER.FTN -----|
C	RASTER.COM	|
C			|				|------RASGEN
C			|-------PTX (driver program)----|
C			|	PTXRAS (raster buffer)	|------PTXOUT (output)
C			|
C			|
C			|				|------RASGEN
C			|-------VERS (driver program)---|
C			|	VERRAS (raster buffer)  |------VEROUT (output)
C			|
C			|
C			|
C			|-------others ???
C
C
C
C	Questions, comments, problems, bugs?
C
C	Please contact me:	Hugh Gregg
C				Physiology or Chemistry Department
C				Michigan State University
C				E. Lansing, Michigan  48824
C				(517) 355-5125
C
C
C	modification history:
C
C	3 april 83	hg	initial edit
C	24 april 83	hg	finished version 1 - all but help files
C
C
C===========================================================================
C