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Diffstat (limited to 'ajde/testdata/examples/spacewar/spacewar/Robot.java')
| -rw-r--r-- | ajde/testdata/examples/spacewar/spacewar/Robot.java | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/ajde/testdata/examples/spacewar/spacewar/Robot.java b/ajde/testdata/examples/spacewar/spacewar/Robot.java new file mode 100644 index 000000000..05f276108 --- /dev/null +++ b/ajde/testdata/examples/spacewar/spacewar/Robot.java @@ -0,0 +1,201 @@ +/* + +Copyright (c) Xerox Corporation 1998-2002. All rights reserved. + +Use and copying of this software and preparation of derivative works based +upon this software are permitted. Any distribution of this software or +derivative works must comply with all applicable United States export control +laws. + +This software is made available AS IS, and Xerox Corporation makes no warranty +about the software, its performance or its conformity to any specification. + +|<--- this code is formatted to fit into 80 columns --->| +|<--- this code is formatted to fit into 80 columns --->| +|<--- this code is formatted to fit into 80 columns --->| + + +Robot.java +Part of the Spacewar system. + +*/ + +package spacewar; + +import java.util.Random; + +/** + * Robot is an automatic pilot that now has quite a bit of intelligence. + * So, beware ! + */ +class Robot extends Pilot implements Runnable { + + private static final int FIRE_INTERVAL = 60; + private static final int REBIRTH_DELAY = 900; + + private final Random random = new Random(); + + private Thread runner; + private boolean runnable = true; + + Robot(Game theGame, int number) { + super(theGame, number); + } + + void start() { + if (runner == null) { + runner = new Thread(this); + runner.start(); + } + } + + void destroy() { + if (runner != null) { + runnable = false; + runner = null; + } + } + + + // A Robot tracks User-controlled ships and fires at them + public void run() { + Ship target = null; + + while(runnable) { + // find target ship + do { + Ship[] potentials = getGame().getRegistry().getShips(); + if(potentials.length != 0) + target = potentials[Math.abs(random.nextInt() % potentials.length)]; + sleepForABit(25); + } while (target == ship); + // main loop + int currentRotation = Ship.STOP; + int time; + boolean currentlyAccelerating = false; + double dx, dy, angleA, angleB, theta, dtheta, d, + targetVel, a, b, c, targetXVel, targetYVel; + + while(true) { + sleepForABit(FIRE_INTERVAL); + + // if my ship is destroyed, give me a new one + if (!ship.isAlive()) { + sleepForABit(REBIRTH_DELAY); + getGame().newShip(this); + } + + // find direction and distance from target to me + dx = ship.getXPos() - target.getXPos(); + if (dx < - getGame().getWidth() / 2) + dx += getGame().getWidth(); + if (dx > getGame().getWidth() / 2) + dx -= getGame().getWidth(); + dy = ship.getYPos() - target.getYPos(); + if (dy < - getGame().getHeight() / 2) + dy += getGame().getHeight(); + if (dy > getGame().getHeight() / 2) + dy -= getGame().getHeight(); + d = Math.sqrt(dx * dx + dy * dy); + angleA = Math.atan(dy / dx); + if (dx < 0) + angleA += Math.PI; + + // find relative velocity and trajectory of target + targetXVel = target.getXVel() - ship.getXVel(); + targetYVel = target.getYVel() - ship.getYVel(); + targetVel = Math.sqrt(targetXVel * targetXVel + + targetYVel * targetYVel); + angleB = Math.atan(targetYVel / targetXVel); + if (targetXVel < 0) + angleB+=Math.PI; + + // find angle between line to target and taget's direction of travel + theta = (angleA - angleB) % (2 * Math.PI); + if (theta < -Math.PI) + theta += 2 * Math.PI; + if (theta > Math.PI) + theta -= 2 * Math.PI; + + // calculate time to bullet impact using law of cosines + a = targetVel * targetVel + Ship.BULLET_SPEED * Ship.BULLET_SPEED; + b = d * targetVel * Math.cos(theta); + c = - d * d; + time = (int)((-b + Math.sqrt(b * b - 4 * a * c)) / 2 / a); + + // calculate angle and distance to bullet impact location + dx = targetXVel * time - dx; + dy = targetYVel * time - dy; + theta = Math.atan(dy / dx); + if(dx < 0) + theta += Math.PI; + + // find desired change in rotation + dtheta = (theta - ship.getOrientation()) % (2 * Math.PI); + // find the shortest path to the desired orientation; + if(dtheta < - Math.PI) + dtheta += 2 * Math.PI; + if(dtheta > Math.PI) + dtheta -= 2 * Math.PI; + + // turn if nessecary + if (dtheta > Ship.DEFAULT_ANGULAR_VELOCITY / 2) { + if (currentRotation != Ship.CLOCKWISE) + ship.rotate(currentRotation = Ship.CLOCKWISE); + } + else if (dtheta < -Ship.DEFAULT_ANGULAR_VELOCITY / 2) { + if (currentRotation != Ship.COUNTERCLOCKWISE) + ship.rotate(currentRotation = Ship.COUNTERCLOCKWISE); + } // otherwise, fire, maybe even a burst + else { + if(currentRotation != Ship.STOP) + ship.rotate(currentRotation = Ship.STOP); + if (random.nextInt() % 40 == 0) { + ship.fire(); + } + } + + // randomly accelerate + if (currentlyAccelerating && random.nextInt() % 2 == 0) + ship.thrust(currentlyAccelerating = false); + else { + if (ship.getXVel() == 0) + angleA = 0; + else + angleA = Math.atan(ship.getYVel() / ship.getXVel()); + + if (ship.getXVel() < 0) + angleA+=Math.PI; + angleB = (angleA - ship.getOrientation()) % (2 * Math.PI); + if (angleB < -Math.PI) + angleB += 2 * Math.PI; + if (angleB > Math.PI) + angleB -= 2 * Math.PI; + angleB = Math.abs(angleB); + + // angleB now represents the angle between the ship's + // orientation and velocity vector. This will be used to + // determine the probably that the ship will thrust to + // prevent ships from accelerating too much in one direction + if (random.nextInt() % (int)(12 * (Math.PI - angleB) + 1) == 0) + ship.thrust(currentlyAccelerating = true); + } + + // switch targets if current one has been destroyed + if (target.getDamage() == 100) + break; + + // randomly switch targets + if (random.nextInt() % 4000 == 0) + break; + } + } + } + + void sleepForABit (int time) { + try { + runner.sleep(time); + } + catch (InterruptedException e) {} + } +} |