--------------------------Tracksail-AI Readme----------------------------------
Tracksail-AI is a modified version of the sailing game tracksail (http://tracksail.sourceforge.net) which is intended to be played by AI players instead of humans.
It's primarly intended to test AI strategies for autonomous sailing robots.
It makes some relatively minor modifications to tracksail to allow tracksail to be controlled by sending commands to a TCP socket listening on port 5555.

The following commands are available:


    set waypoint - jumps to the next waypoint

    set rudder x - sets rudder to position x (270 to 90 centreing on 0)

    set sail x - sets the sail to position x (270 to 90 centreing on 0),
    the sail may not actually move to your desired position if that position is on the opposite tack or lets the sail out too far when close hauled.

    set unwind - this causes tracksail to exit. The unwind command is a throwback to an early sailing robot which had a continous rotation mast and tended to wrap a cable around it.

    get wind_dir - gets the wind direction relative to the boat.

    get compass - gets the current heading of the boat.

    get waypointdir - gets the dirction to the next waypoint (known as ports in tracksail). This will be halfway between the two buoys. It is recommended that both the 
    port and starboard buoy be set to the same position, however they can't be identical and must differ by at least one. See tracks/AI.track for an example.

    get waypointnum - gets the number of the next waypoint.

    get waypointdist - gets the distance to the next waypoint (in metres?).

    get sail - gets the sail position

    get northing - gets the Y coordinate of the boat's position, equivalent to a GPS northing or latitude

    get easting - gets the X coordinate of the boat's position, equivalent to a GPS easting or longitude

    An example client program written in C using a simple control strategy is available in the example_client directory.

Starting tracksail-AI:

    Tracksail needs to be started in two parts the server and the client. The shell scripts server.sh and client.sh will start the two parts.
    Alternatively the script start_tracksail.sh runs both, it also kills any existing processes and any existing rmiregistry processes. Be carfeul as
    this may affect over RMI based Java applications which might be running. The whole program takes about 20 or 30 seconds to start. Do not attempt to
    run a simulator client until everything has started up.

    These scripts have been tested under both SunOS 5.10 and Ubuntu Linux 8.04 (Hardy LTS). Theoretically they should work on OSX and other Linux distributions
    but this hasn't been tested yet. With a small amount of work they should work on Windows but this has not been tested either.

    Tracksail-AI has only been tested under the Sun Java VM versions 1.5 and 1.6.

Limitations of tracksail-AI as a sailing robot simulator.

    Lag times are far too low. In a real robot actuators can take several seconds to move the rudder or sail into a new position, in tracksail they move instantly.
    It also doesn't suffer from problems with actuator repeatability or accuracy.
    The physics engine doesn't simulate waves and the way wind varies is not very realistic.
    
    Often algorithms which work in tracksail don't work in the real world. However algorithms which fail in tracksail generally fail in the real world too
    so it can be a good way to eliminate things which will never work. 
    
Changes from original Tracksail:

    Changed the startup screen so the whole game starts automatically. This breaks being able to add multiple players and always loads the track default.track.
    Changed the way the rudder behaves so that the rudder stays in the position that you leave it in.
    A waypoint is now considered to have been reached when the boat gets within 15m of it. 
    Changed the background tile to be plain blue, this was to reduce bandwidth when running the client over VNC.