NAME

dog − cooperative or competitive flight simulator and airshow generator

SYNOPSIS

/usr/people/demos/dog [  −i infile  ] [  −o outfile ]

DESCRIPTION

The dog demonstration program is an enhanced version of the flight(1D) demonstration program for use on multiple IRIS workstation systems. Each IRIS determines the position of its aircraft several times a second, broadcasts the plane’s location and orientation to the other IRIS systems running dog, and listens to the other planes’ locations. All known planes in the current field of view are displayed on all systems.

If neither −inor −o is selected, the broadcast medium is the Ethernet.  Otherwise, the media are the specified files.  Ethernet is assumed for the combat described below.  For the file options, see Airshow Option. 

Pilots may cooperate by attempting formation aerobatics or compete by trying to shoot each other down.  The coordinates of projectiles are included in the Ethernet packets, hits are detected, and scoring is maintained. 

Weapons

Fighters are armed with rockets, sidewinders, and cannon.  The number of rockets and sidewinders available on each type of fighter are indicated on the help display. Landings replenish missiles as well as fuel.  The number of missiles replenished depends on the quality of the landing (see flight(1D). Ammunition for the cannon is inexhaustible.

Each weapon has a different kill radius. Weapons detonate themselves when they are within their kill radius of a plane other than the one they came from.  All planes within the kill radius of an exploding weapon are destroyed. 

The q key fires a rocket.  Rockets have about ten seconds of fuel and follow ballistic paths after the fuel is exhausted.  They explode when they strike the ground, come within range of an aircraft (except the one they came from), or are destroyed by their owner.  Rockets have the largest kill radius of all the weapons. 

The w key fires a sidewinder.  Sidewinders are like rockets but track, or steer themselves towards, other aircraft if they are “locked on”.  Sidewinders are locked on if they are fired while a target aircraft is in the orange tracking rectangle or if locked on with the t key.  The t key identifies the target and locks a sidewinder onto the target for one second without firing the weapon.  This is useful for identifying other planes as friend or foe. Sidewinders will not lock on aircraft lower than 150 feet, but once they are locked on, they will track a plane below 150 feet.  Sidewinders stop tracking and follow ballistic paths when they run out of fuel. The Cessna 150 does not generate enough heat to attract sidewinders.  A good pilot can usually outmaneuver a sidewinder unless his plane is traveling slowly with a heavy load.  Sidewinders have a smaller kill radius than rockets. 

The e key fires a cannon round.  The cannon has a limited range—each cannon shell exists for only one second. Cannons have the smallest kill radius. 

The r key destroys the current missile.  Any aircraft in range of the explosion is destroyed. Each aircraft can have only one projectile in the air at a time.  Thus, you can destroy missiles that have missed their targets allowing new ones to be fired.  In flight, or in dog with no competition, strafing the airport can be good practice for the real thing. 

Scoring

dog keeps track of victories and defeats.  A pilot scores a “won” when a projectile fired by his plane destroys another aircraft.  A pilot scores a “lost” when his aircraft is destroyed by a projectile or crashes. 

Each pilot’s score is displayed on his instrument panel.  The scores of all the current players are shown to each new player when he joins the game and when he reincarnates himself after destruction. 

When a player joins the game, an announcement is broadcast to all players.  Messages are also broadcast whenever a player quits, destroys another plane, or is destroyed. 

Airshow Option

The −o option will record the path of your aircraft on outfile rather than broadcasting it to the network. 

The −i option replays a recorded flight.  You will be in another aircraft, able to join the other recorded planes in formation or shoot at, but not destroy them. 

Specifying both the −i and −o options replays a recorded flight and produces an outfile containing your aircraft’s path as well as the other planes’ paths.  infile and outfile cannot be the same file.  Repeated use of the command can make formations of many aircraft. 

SEE ALSO

flight(1D), radar(1D), shadow(1D)

AUTHOR

Gary Tarolli

NOTES

Various kinds of cheating are possible, e.g., temporarily selecting the night display to better see a distant opponent’s exhaust.  Some scrupulous pilots avoid operations not possible in real aircraft.  Others use every trick possible. 

The Cessna 150 and B-747 have 20mm cannon.  This is inaccurate but amusing in the C-150 (the 747 is much too sluggish).  Try taking off in the C-150 and flying around the runway, picking off opponents as they appear.  Since the Cessna does not attract sidewinders, it has a chance to survive.  If you make a mistake and take off in the 747, you are dogmeat. 

BUGS

The cannon ammunition should be finite and the cannon should overheat and jam if used too often. 

dog core dumps if more than 15 planes join the game. 

Version 2.5r1  —  October 29, 1986