bullet.java

坦克大战中子弹的源代码

package com.ccu.whj;
import java.awt.*;
import java.util.List;
import java.util.ArrayList;
import java.awt.Toolkit;


/**
 * 子弹类
 * @author 王洪吉
 *
 */
public class Bullet {
	
	//子弹的位置
	private int bx = 120, by = 120;
	//子弹的大小（静态常量）
	private static final int B_WIDTH = 10,B_HEIGHT = 10;
	
	//子弹速度（静态常量）
	private static final int BSPEED = 15;
	//子弹是否健在
	private boolean live = true;
	//子弹的移动方向
	Direction bDir;
	//取得大管家的引用
	private TankWarClient tc;
	//子弹是谁发射的，我方还是敌方，我方good == true
	private boolean good = true;

	//将使用Toolkit中的方法把硬盘上的图片拿到内存里来
	private static Toolkit tk = Toolkit.getDefaultToolkit();
	
	private static Image[] bulletImgs = null;
	
	static {
		bulletImgs = new Image[] {
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletL.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletLU.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletU.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletRU.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletR.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletRD.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletD.gif")),
			tk.getImage(Bullet.class.getClassLoader().getResource("images/bulletLD.gif"))
		};		
	}

	public Bullet(int x, int y, Direction dir) {
		this.bx = x;
		this.by = y;
		this.bDir = dir;
	}
	
	public Bullet(int x, int y, Direction dir, TankWarClient tc) {
		this(x,y,dir);
		this.tc = tc;
	}
	
	public Bullet(int x, int y, Direction dir, TankWarClient tc, boolean good) {
		this(x,y,dir,tc);
		this.good = good;
	}
	
	public void draw(Graphics g) {
		if(!live) return;
		
		switch(bDir) {
		case L:
			g.drawImage(bulletImgs[0], bx, by, null);
			break;
		case LU:
			g.drawImage(bulletImgs[1], bx, by, null);
			break;
		case U:
			g.drawImage(bulletImgs[2], bx, by, null);
			break;
		case RU:
			g.drawImage(bulletImgs[3], bx, by, null);
			break;
		case R:
			g.drawImage(bulletImgs[4], bx, by, null);
			break;
		case RD:
			g.drawImage(bulletImgs[5], bx, by, null);
			break;
		case D:
			g.drawImage(bulletImgs[6], bx, by, null);
			break;
		case LD:
			g.drawImage(bulletImgs[7], bx, by, null);
			break;
		}
		move();
	}
	
	public void move() {
		
		switch(bDir) {
		case L:
			bx -= BSPEED;
			break;
		case LU:
			by -= BSPEED;
			bx -= BSPEED;
			break;
		case U:
			by -= BSPEED;
			break;
		case RU:
			by -= BSPEED;
			bx += BSPEED;
			break;
		case R:
			bx += BSPEED;
			break;
		case RD:
			by += BSPEED;
			bx += BSPEED;
			break;
		case D:
			by += BSPEED;
			break;
		case LD:
			by += BSPEED;
			bx -= BSPEED;
			break;
		}
		/*
		 * 子弹出界则消失
		 */
		if(bx<0 || bx>800 || by<0 || by>600) {
			tc.bullets.remove(this);
		}		
	}
	
	/**
	 * 子弹击中坦克的实现
	 * @param t 被击中的坦克
	 * @return 击中则返回true，否则返回false
	 */
	public boolean hitTank(Tank t) {
		/*
		 * 碰撞检测，并且判断双方均为live状态，且双方互为敌人
		 */
				if(this.live && this.getRect().intersects(t.getRect()) && t.isLive() && this.good != t.isGood()) {
					/*
					 * 当击中我方坦克时，扣血，直至0血死亡
					 */
					if(t.isGood()) {
						int i = t.getLife();
						i = i - 8;
						t.setLife(i);
						if(i <= 0) {
							t.setLive(false);
						}
						this.live = false;
					} else {
						/*
						 * 击中敌方boss扣血，0血死亡
						 */
						if(t.isKing()) {
							int i = t.getKingLife();
							i = i - 1;
							t.setKingLife(i);
							if(i <= 0) {
								t.setLive(false);
								tc.score += 100;
							}
						} else {
							/*
							 * 击中敌方普通小兵，直接打死
							 */
							t.setLive(false);
							tc.score += 1;
						}
						//击中任何坦克，子弹都应死亡
						this.live = false;
					}
					//产生爆炸
					tc.explodes.add(new Explode(t.getX(), t.getY(),tc));
					return true;
				}
		return false;
	}
	
	/**
	 * 用以实现使子弹能够打击所有容器内的坦克
	 * @param tanks 容器类的实例
	 * @return 击中则返回true，否则false
	 */
	public boolean hitTanks(List<Tank> tanks) {
		for(int i = 0; i < tanks.size(); i++) {
			Tank t = tanks.get(i);
			if(hitTank(t)) {
				return true;
			}
		}
		return false;
	}
	
	/**
	 * 
	 * @param w 被撞的墙
	 * @return 子弹撞墙则返回true，否则false
	 */
	public boolean hitWall(Wall w) {
		if(this.getRect().intersects(w.getRect())) {
			this.live = false;
			return true;
		}
		return false;
	}
	
	/**
	 * 碰撞检测，得先把对象的矩形都拿到
	 * @return 子弹的矩形范围
	 */
	public Rectangle getRect() {
		return new Rectangle(bx,by,B_WIDTH,B_HEIGHT);
	}
	
	/**
	 * 子弹与子弹相撞
	 * @param b 被击中的子弹
	 * @return 击中则返回true，否则false
	 */
	public boolean hitBullet(Bullet b) {
		if(this.live && this.getRect().intersects(b.getRect()) && b.live && this.good != b.isGood()) {
			this.live = false;
			return true;
		}
		return false;
	}
	
	/**
	 * 用以实现与所有子弹都能相撞
	 * @param bullets 容器类的实例
	 * @return 相撞则返回true，否则false
	 */
	public boolean hitBullets(List<Bullet> bullets) {
		for(int i = 0; i < bullets.size(); i++) {
			Bullet b = bullets.get(i);
			if(hitBullet(b)) {
				return true;
			}
		}
		return false;
	}

	public boolean isLive() {
		return live;
	}

	public void setLive(boolean live) {
		this.live = live;
	}

	public boolean isGood() {
		return good;
	}

	public int getBx() {
		return bx;
	}

	public int getBy() {
		return by;
	}
}