Android Open Source - libgdx-demo-pax-britannica Fighter A I

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License

The source code is released under:

Copyright (c) 2010 Ben Abraham, Renaud B?dard, Henk Boom, Daniel Burton, Matthew Gallant Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated ...

Java Source Code

package de.swagner.paxbritannica.fighter;
//  w  w  w .ja  va2  s .  c o m
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.math.Vector2;

import de.swagner.paxbritannica.Ship;
import de.swagner.paxbritannica.Targeting;

public class FighterAI {
  // shot range
  private float shot_range = 200;

  // try to stay this far away when you're out of ammo
  private float run_distance = 200;

  // true when we've shot everything and want to make a distance, false means
  // we're approaching to attack
  private boolean running = false;

  public Ship target;
  private boolean on_screen = true;
  
  //recycle vars
  Vector2 to_target = new Vector2();

  private Fighter fighter;

  public FighterAI(Fighter fighter) {
    this.fighter = fighter;
    retarget();
  }

  public void retarget() {
    target = Targeting.getNearestOfType(fighter, 1);
    if (target == null) {
      target = Targeting.getNearestOfType(fighter, 0);
    }
    if (target == null) {
      target = Targeting.getNearestOfType(fighter, 2);
    }
    if (target == null) {
      target = Targeting.getNearestOfType(fighter, 3);
    }
  }

  public void update() {
    // if we go from on to off screen, retarget
    boolean new_on_screen = Targeting.onScreen(fighter.collisionCenter);
    if (on_screen && !new_on_screen || target == null || !target.alive || MathUtils.random() < 0.005f) {
      retarget();
    }
    on_screen = new_on_screen;

    if (target != null) {
      to_target.set(target.collisionCenter.x - fighter.collisionCenter.x, target.collisionCenter.y - fighter.collisionCenter.y);
      float dist_squared = to_target.dot(to_target);

      if (running) {
        // run away until you have full ammo and are far enough away
        boolean too_close = dist_squared < Math.pow(run_distance, 2);
        // if you're too close to the target then turn away
        if (too_close) {
          fighter.goAway(target.collisionCenter, true);
        } else {
          fighter.thrust();
        }

        if (!fighter.isEmpty() && !too_close) {
          running = false;
        }
      } else {
        // go towards the target and attack!
        fighter.goTowards(target.collisionCenter, true);

        // maybe shoot
        if (fighter.isReadyToShoot()) {
          if (dist_squared <= shot_range * shot_range && to_target.dot(fighter.facing) > 0 && Math.pow(to_target.dot(fighter.facing), 2) > 0.97 * dist_squared) {
            fighter.shoot();
          }
        }

        // if out of shots then run away
        if (fighter.isEmpty()) {
          running = true;
        }
      }
    }
  }
}

Java Source Code List

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