Targeting.java

package de.swagner.paxbritannica;

import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.utils.Array;

import de.swagner.paxbritannica.bomber.Bomber;
import de.swagner.paxbritannica.factory.FactoryProduction;
import de.swagner.paxbritannica.fighter.Fighter;
import de.swagner.paxbritannica.frigate.Frigate;

public class Targeting {

	public static boolean onScreen(Vector2 position) {
		return onScreen(position, 0);
	}

	public static boolean onScreen(Vector2 position, float buffer) {
		return position.x >= Constants.screenLeft - buffer && position.x <= Constants.screenRight + buffer && position.y >= Constants.screenBottom - buffer
				&& position.y <= Constants.screenTop + buffer;
	}

	/*
	 * returns the closest target of the given type 0 = Fighter 1 = Bomber 2 =
	 * Frigate 3 = Factory
	 */
	public static Ship getNearestOfType(Ship source, int shipType) {
		if (shipType == 0)
			return getNearestOfType(source, GameInstance.getInstance().fighters);
		else if (shipType == 3)
			return getFactoryWithHighestHealth(source, GameInstance.getInstance().factorys);
		else if (shipType == 1)
			return getNearestOfType(source, GameInstance.getInstance().bombers);
		else if (shipType == 2)
			return getNearestOfType(source, GameInstance.getInstance().frigates);
		else
			return null;
	}

	private static Ship getFactoryWithHighestHealth(Ship source, Array<Ship> ships) {
		// find the closest one!
		Ship closestShip = null;
		float highestHealth = Float.MIN_VALUE;

		for (int i = 0; i < ships.size; i++) {
			Ship ship = ships.get(i);
			float currentHealth = ship.hitPoints+(((FactoryProduction)ship).harvestRate*500);

			if (ship.alive && source.id != ship.id && onScreen(ship.collisionCenter) && (currentHealth > highestHealth)) {
				closestShip = ship;
				highestHealth = currentHealth;
			}
		}

		return closestShip;
	}
	
	private static Ship getNearestOfType(Ship source, Array<Ship> ships) {
		// find the closest one!
		Ship closestShip = null;
		float closestDistanze = Float.MAX_VALUE;

		for (int i = 0; i < ships.size; i++) {
			Ship ship = ships.get(i);
			float currentDistance = source.collisionCenter.dst(ship.collisionCenter);

			if (ship.alive && source.id != ship.id && onScreen(ship.collisionCenter) && (currentDistance < closestDistanze)) {
				//skip if ship is not targeting source ship
				if(ship instanceof Fighter) {
					if(((Fighter) ship).ai.target!=null && ((Fighter) ship).ai.target.id != source.id) {
						continue;
					}
				}
				if(ship instanceof Bomber) {
					if(((Bomber) ship).ai.target!=null && ((Bomber) ship).ai.target.id != source.id) {
						continue;
					}
				}
				if(ship instanceof Frigate) {
					if(((Frigate) ship).ai.target!=null && ((Frigate) ship).ai.target.id != source.id) {
						continue;
					}
				}
				closestShip = ship;
				closestDistanze = currentDistance;
			}
		}

		return closestShip;
	}

	/*
	 * return a random ship of the desired type that's in range
	 * 0 = Fighter 1 = Bomber 2 = Frigate 3 = Factory
	 */
	public static Ship getTypeInRange(Ship source, int shipType, float range) {
		if (shipType == 0)
			return getTypeInRange(source, GameInstance.getInstance().fighters, range);
		else if (shipType == 3)
			return getTypeInRange(source, GameInstance.getInstance().factorys, range);
		else if (shipType == 1)
			return getTypeInRange(source, GameInstance.getInstance().bombers, range);
		else if (shipType == 2)
			return getTypeInRange(source, GameInstance.getInstance().frigates, range);
		else
			return null;
	}

	/**
	 * return a random ship of the desired type that's in range
	 */
	private static Ship getTypeInRange(Ship source, Array<Ship> ships, float range) {
		Array<Ship> shipsInRange = new Array<Ship>();
		float range_squared = range * range;

		for (int i = 0; i < ships.size; i++) {
			Ship ship = ships.get(i);
			float currentDistance = source.collisionCenter.dst(ship.collisionCenter);

			if (ship.alive && source.id != ship.id && onScreen(ship.collisionCenter) && (currentDistance < range_squared)) {
				shipsInRange.add(ship);
			}
		}

		if (shipsInRange.size > 0) {
			return shipsInRange.get(MathUtils.random(0, shipsInRange.size - 1));
		} else {
			return null;
		}
	}
}