$Id: README,v 1.7 89/09/21 10:58:11 mbp Exp $

				 viewwld

				   by
			    Mark B. Phillips
			   mbp@lakisis.umd.edu
				    
			Department of Mathematics
			 University of Maryland
			 College Park, MD  20742

 ************************************************************************
 *		Copyright (C) 1989 by Mark B. Phillips                  *
 * 									*
 * Permission to use, copy, modify, and distribute this software and    *
 * its documentation for any purpose and without fee is hereby granted, *
 * provided that the above copyright notice appear in all copies and    *
 * that both that copyright notice and this permission notice appear in *
 * supporting documentation, and that the name of Mark B. Phillips or   *
 * the University of Maryland not be used in advertising or publicity   *
 * pertaining to distribution of the software without specific, written *
 * prior permission.  This software is provided "as is" without express *
 * or implied warranty.                                                 *
 ************************************************************************

This directory and its subdirectories contain viewwld, an interactive
viewing program for 3 dimensional line drawings.  Viewwld will read an
ascii input file containing a description of the picture, and will display
the picture in a window.  It provides an interactive control panel with
buttons for turning the picture around, zooming in and out, etc.

Viewwld is simple.  It can display only line segments and points in space
--- no shaded or hidden-line images of surfaces or solids, etc.  Because
of its simplicity, however, it is fast and works well for displaying
simple to moderately complicated line drawings.  It is especially good at
providing an intuitive way to turn your picture around and explore it
from different points of view.

Viewwld creates 'world' files, which are condensed binary versions of
the data in your (ascii) input file.  Once a world file has been
created, you can use viewwld to view it later.  This is much faster
than re-reading the original input data.

The files 'house.vec' and 'lorenz.vec' in the 'viewwld' subdirectory
are sample input vector files.  To run viewwld on house.vec, for
example, give the command 'viewwld house.vec'.

Viewwld runs only under Suntools.

To compile and/or install, see the instructions in the Makefile.

Viewwld comes with two C libraries: GR and LGD.  GR serves as the
basic interface to the SunView window system and 2D graphics.  LGD,
which is built on top of GR, provides 3D graphics capability.  GR and
LGD may be used independently of viewwld.  For instructions on how to
install these libraries independently of viewwld, see the Makefiles in
the 'gr' and 'lgd' subdirectories.  If you do this, do not use the
viewwld Makefile in this directory.  You should first install GR and
LGD (in that order), following the instructions in the files
gr/Makefile and lgd/Makefile.  Then install viewwld manually by
following the instructions in the file viewwld/Makefile.

Viewwld and its associated libraries are under continuing development,
and I welcome all comments, suggestions, criticisms, questions, etc.  The
main reason I wrote viewwld was to provide an intuitive, fast, and easy
way of viewing 3-dimensional data on Sun workstations which are not
necessarily equipped with any special graphics hardware.  My primary
guiding principal was that it should provide intuitive control over the
way it displays the picture.  This means that viewing an object with
viewwld should be as similar as possible to actually exploring an object
in real life.  I am especially interested in suggestions on how to make
viewwld better in this way.

						mbp
						September 20, 1989
