Introduction:
-------------
Graphplace is a utility to do placement of graphs,
and produce a viewable and printable picture of them.
It is made as a general utility, to be used among widely different
applications. For this purpose flexibility was a major design goal.
It consists of two distinct components:
1. An ANSI-C sourcecode program 'graphplace', to be compiled and installed
   on your system. This program will compute [x,y] coordinates for
   the nodes (vertices) of a graph. The program acts as a filter:
   translating an inputfile to an outputfile.
   The placement heuristic is very fast, allowing interactive use
   with graphs of thousands of nodes.
   The I/O files follow a very simple and loose format.
2. A postscript program which can visualise the filtered data.
   This allows previewing by means of a general postscript previewer
   such as for instance 'gv', and direct printing of the graphs
   on a postscript printer.
Since its first release in april 1993, 'graphplace' has been adopted by
hundreds of sites all over the world.

Release Notes:
--------------
This is the second main release of our `graphplace' program.

Its main new feature is routing long edges between the nodes,
invoked by the -y or -z option.

Depending on your previous version,
the capability to vertically align indicated groups of nodes,
or to discard certain edges during placement, might seem new to you also.

Support for non-european papersizes is newly added,
and a couple of minor bugs have been repaired since the first version.

To aid new and innocent users, the -s and -u options were removed
(set always 'on'), and '-i-' is set by default in postscript mode.

These modifications are reflected in the updated manualpage.

Installation:
-------------
After unpacking you will find the following files belonging to this
distribution:
	Makefile
	README
	defines.h
	files.c
	graphplace.1
	graphplace.1.ps
	graphpro.ps
	hash.c
	main.c
	mem_alloc.c
	place.c
	scale.c

 
In the Makefile you might want to edit the compilation flags for your system.
You will need a real ANSI-C compiler to make the executable.

The graphplace.1 file is intended for installation in a UNIX online manual
directory, such as /usr/local/man/man1.
The graphplace.1.ps is the same manual page, formatted for postscript printing,
just to aid those sites who cannot do such formatting.

The graphpro.ps is a postscript prologue. It is intended to be installed
somewhere system-wide, such that it can be found by the executable upon
invocation by a user. Upon invocation (runtime) the executable tries to locate
this file along a sequence of directories. You might want to edit this
searchpath in 'files.c' at line 200 ('static char *dirs[] =').

The default papersize in postscript mode is 'a4' in this distribution.
You can change this to 'letter' or something else, in 'files.c' at
line 263 ('char *box_default = "a4";').

Be sure to reflect these changes (papersize and search directories)
or just precise your situation in the graphplace.1 manual page,
before installing the manual:
line 129:  A4 or Letter, chosen at installation time
line 187:  'a4' (or 'letter' depending upon installation)
line 226:  directories: "." "$HOME/lib" "/usr/local/lib/ps" "/usr/local/lib"
line 229:  residing in '/usr/local/lib'

You can now create the executable by typing just 'make'.
After compilation you can try an example as shown near the end of the manual
page.


Success!
-------
You are invited to let me know if you are installing `graphplace'
to be used with some application. This holds in particular if you intend
to redistribute `graphplace' bundled with your own application.

Jos van Eijndhoven
Eindhoven University of Technology
P.O. box 513
5600 MB  Eindhoven
The Netherlands
phone: +31-40-473612
email: J.T.J.v.Eijndhoven@ele.tue.nl

August 1994
