1. Introduction
---------------
The Virtual Air project intends to provide a standartized (HLA 1.3 based)
framework for distributed air traffic simulation.
http://virtualair.sourceforge.net

This module provides a HLA 1.3 interface for the FlightGear flight simulator.
http://www.flightgear.org

It should be compatible with any HLA RTI (Run Time Infrastructure). It was
tested with the CERTI, which is an open-source RTI (under GPL)
http://www.cert.fr/CERTI
http://savannah.nongnu.org/projects/certi

The used federation object model (FOM) intends to be compliant with
the RPR FOM 1.0 specified in SISO-STD-001.1-1999.
http://www.sisostds.org/index.php?tg=articles&idx=More&article=40&topics=18


2. Build Instructions
---------------------

1) Install a HLA 1.3 compliant RTI.

This module was tested the latest CERTI HLA infrastructure (CVS head).
http://savannah.nongnu.org/projects/certi/

Please use cmake to create the Makefile and follow the CERTI build instructions.

2) Obtain the latest FlightGear sources (CVS head).

3) Install the patch.

  cp hla.{cxx,hxx} source/src/Network
  cp hla.patch source/src

  cd source
  patch -p0 < hla.patch

4) Build the FlightGear.

Please follow the FlightGear build instructions.

  ./autogen.sh
  ./configure --with-hla=/usr/local
  make

5) Supply each simulation module with the "VirtualAir.fed" file.

Copy "VirtualAir.fed" to directory(ies) where the CERTI and FlightGear binaries
are installed (e.g. /usr/local/bin).


3. User Instructions
--------------------

Before using the FlightGear HLA interface, a HLA RTI must be started

  rtig


The FlightGear HLA interface can be enabled via the command line

  export CERTI_HOST=<rtig>
  fgfs --callsign=[<callsign>] --hla=<rate>,<federate>,<federation>[,<model>]

where

  <rtig>        Address of a machine on which the RTIG is running.
  <callsign>    Object name. Identification of this FlightGear. If not given,
                this FlightGear will not be visible to others (stealth mode).
  <rate>        Refresh rate [sec]. Determines how often this FlightGear should
                distribute updated information about own position.
  <federate>    Federate name. A unique identification of this FlightGear in the
                federation (simulation).
  <federation>  Federation name. Determines what federation this FlightGear
                should join. Should be set to "VirtualAir".
  <model>       Federation object model (FOM). Determines a .fed file that
                describes the federation being joined.
                If not given, "<federation>.fed" is used by default.


$Id: README 6 2008-06-01 12:21:09Z gotthardp $
