************************************************************************
* Project:   AERO
* Filename:  INSTALL
* Date:      Sat Aug 31 18:07:37 1996
* Author:    Hartmut
*
* Description:
* ------------
* This text shows how to compile and install xaero.
************************************************************************


This is the free xaero release. For further information about AERO in
general please refer to the file README. The "official" AERO site is

  http://www.informatik.uni-stuttgart.de/ipvr/bv/aero/

and the newest AERO version can be obtained via

  ftp://ftp.informatik.uni-stuttgart.de/pub/AERO


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


BUILD xaero:
------------

To compile this release you need:

    - X-Windows libraries (best: X11R5 or newer)
    - Athena-Widget-Set (supplied with X-Windows)
    - FWF-library (Free Widget Foundation, V4.0 recommended)
    - ANSI-C Compiler (e.g. gcc 2.3.3 or newer)

(Remark: when using V4.0 or newer of FWF, you don't need the
XPM-library anymore) 

1. Install the FWF library. This may be the toughest part of the whole
   installation procedure. There is a special README.fwf file that
   gives some hints about doing this.

2. cd to the src directory. Choose the appropriate Makefile for your
   machine and copy it to the name "Makefile". Edit this and modify
   the entries at the beginning to resemble your machine environment.
   The Makefile gives detailed instructions on how to do this. You can
   type "make help" to recheck your path settings. 

   If your machine is not directly supported in the Makefiles, use
   Makefile.solaris (on System V machines) or Makefile.sunos (on BSD
   machines) as a starting point for modifications of your own
   Makefile. If your compiler/linker does not support alternating use
   of static and dynamic link mode, use Makefile.linux to start from. 

3. Type "make" to compile xaero. If everything works fine and you want
   to install xaero in a global path, type "make install".

   If you are lucky to have a Silicon Graphics machine and want to
   compile the special Inventor version, use "make invxaero" and 
   "make invinstall" instead. There is a special README.inventor that
   deals with this version.


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


APPLICATION DEFAULTS:
---------------------

When you start xaero and get an error like 

    Error: Widget EM_Darstellung3D has zero width and/or height

then you have not installed the application default file (XAero)
correctly; or your system simply doesn't find it. So here is a short
and simplified explanation of how X searches for this file.

a) First of all, X checks for an environment variable
   $XUSERFILESEARCHPATH. If it exists, it looks for the paths in it.
   Usually there are some %-abbreviations in the path wich are replaced 
   by actual parameters during program startup. If $XUSERFILESEARCHPATH 
   does not exist, X assumes a default value for it with some standard
   paths relative to your $HOME directory (!) and relative to another
   environment variable $XAPPLRESDIR. Even the $LANG variable may have
   influence of where the file is found. This usually results in
   something like 

	$APPLRESDIR/$LANG/
	$APPLRESDIR/
	$HOME

   $XUSERFILESEARCHPATH and $XAPPLRESDIR can be set by the user.

b) Second, X looks for an environment variable $XFILESEARCHPATH, which
   is processed in the same way as $XUSERFILESEARCHPATH and which has
   its own default if not present. This results in some global standard
   places of X-Windows, typically

	/usr/local/X11R5/lib/X11/app-defaults/$LANG/
	/usr/local/X11R5/lib/X11/app-defaults

   $XFILESEARCHPATH should only be set by the system administrator.

(Refer to the Xlib and Xt C-reference manuals provided with the
X-Windows distribution for an exact definition of this.)

So here we have two different strategies:


Install XAero in a global path (only for sysadmins):
----------------------------------------------------
Put the application defaults file in a path where the system looks
anyway, i.e. /usr/local/X11R5/lib/X11/app-defaults. If this is not
appropriate, you have to set and/or augment the $XFILESEARCHPATH
variable to include the new directory. This has to be done in an
early stage of environment setting (e.g. a global cshrc file) and can
look something like this (assuming the above default paths):

setenv XFILESEARCHPATH /usr/local/X11R5/lib/X11/%L/%T/%N%S:\
/usr/local/X11R5/lib/X11/%T/%N%S:/usr/local/lib/%L/%T/%N%S:\
/usr/local/lib/%T/%N%S

From now on you can put those application defaults files also under
/usr/local/lib/app-defaults and anybody on the system will get it
right. 


Install XAero locally anywhere in $HOME:
----------------------------------------
The easiest way is to put XAero directly in your home directory $HOME.
But often it is annoying to have such files cluttering this main
directory. So you want it somewhere else. Usually you simply have to
set $XAPPLRESDIR to point to $HOME/app-defaults and put XAero there.

But as you see from the path list above, $XAPPLRESDIR can only contain
one single path, as it is in fact only part of a longer path built
from $XUSERFILESEARCHPATH. So if you really need to have more than one
path with application default files, you have to set or modify the
$XUSERFILESEARCHPATH variable in a similar way as described above for
$XFILESEARCHPATH. Here you only need to check for your own local paths
and therefore you probably have to include $XAPPLRESDIR somewhere in
it or you loose your previous path settings.


Summary:
--------
System administrators move the application defaults file XAero to the
X-Windows standard path (/usr/local/X11R5/lib/X11/app-defaults,
$OPENWINHOME/lib/app-defaults, ...) or modify $XFILESEARCHPATH.

Other users move it to $HOME, or set $XAPPLRESDIR to $HOME/app-defaults 
and move it there, or modify $XUSERFILESEARCHPATH.

By the way, if nothing works, you can merge the XAero application
resources to your session-global resources by saying

  xrdb -merge XAero

This remains active for the rest of the session (=logout) or until
another xrdb command cancels this action.

You can always check the resources by giving the command 

  appres XAero

When this lists all XAero* resources (probably among some others),
everything is ok.


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


Bugs, suggestions or problems can be reported via email to

   keller@informatik.uni-stuttgart.de  (Hartmut Keller)      or
   braunl@informatik.uni-stuttgart.de  (Thomas Braeunl)      or
   stolz@isa.de	                       (Horst Stolz)
