$Id: README,v 1.3 2000/10/20 05:20:59 cho Exp $

This file describes the installation of nviz version 2.2.  For
additional information on using nviz, there is a man page in this
directory which you can install as appropriate. 

INSTALLATION
------------

nviz requires Tcl 8.x and Tk 8.x.  A special Tk 8.0 compatible version
of the tkGLX 1.3.2 widget is supplied with this distribution.  Earlier
versions of Tcl and Tk are not acceptable as major design
modifications were made in Tk 8.0.

To install:

1. PostgreSQL support is selected by global "configure".
   You can either 
   - change that by using the --with-postgresql parameter
     when calling the global GRASS "configure" or
   - override global setting for PostgreSQL by an environment variable:

         env PGSQL=NO gmake5

2. Make the distribution in this directory with:
	gmake5

The Gmakefile in this directory first builds the C portion of
nviz and the gsf library, and then builds and installs the Tcl scripts
in the appropriate GRASS directories.  After installing nviz you may
remove any of the subdirectories contained in the distribution except
for the bitmaps and scripts directories.  Furthermore, note that the
location of the Tcl scripts is compiled into nviz.  This means that if
you need to move these scripts for some reason you will most likely
have to reinstall nviz.  

CHANGES FROM VERSION 1.0
------------------------

No significant changes have been made from version 1.0 to 2.0 other
than a complete port to Tk 4.0 with all the benefits which that
entails.  All functionality provided by version 1.0 is still supported
but with a much cleaner interface.

KNOWN BUGS
----------
Scripting: There are a few subtle "features" in the scripting
  interface of nviz.  In particular, if users add their own panels
  old scripts may have unpredictable behavior.  However, any script
  created with the "Script File Tools" option under "Script Tools"
  will be unaffected.

Some features of Sg3D are not yet implemented.
