tankgame611.java

1) 图像的基本操作； 2) ImageObserver接口、ImageProducer接口的应用； 3) FilteredImageSource类、ImageFilter类、CropImageF

package tankgame611;

import java.awt.*;
import java.awt.Image;
import java.applet.*;
import java.applet.Applet;
import java.awt.Graphics;
import java.awt.MediaTracker;
import java.util.Random;

public class TankGame611 extends Applet {
  final int EnemyNum=4;
  int myTankWidth, myTankHeight;
  int enemyTankWidth,enemyTankHeight;
  int enemyTankX,enemyTankY;
  int myTankX, myTankY;
  int destroyEnemyNum=0;
  Image myTankSrcImg;
  Image enemyTankSrcImg;
  Image shellSrcImg;
  Image bufferImage;
  Image bckImage;
  Image myTankImg[];
  Image enemyTankImg[];
  Graphics bufferGraphic;
  MediaTracker MT;
  PlayTankSprite myTankSprite;
  EnemyTankSprite[] enemyTank;
  TankThread threadTank;
  ShellSprite MyShell;
  ShellSprite[] enemyShell;
  public Image shellImg[];
  Explosion explosion;
  Image explosionImg[];
  Image explosionSrcImg;
  private AudioClip explAudio,bkMusicAudio,gameOverAudio;
  Random rand;
  public void init() {
    MT = new MediaTracker(this);
    bckImage = getImage(getDocumentBase(), "pic/Bckscrn.png");
    MT.addImage(bckImage, 0);
    myTankImg = new Image[4];
    enemyTankImg = new Image[4];
    shellImg = new Image[2];
    bkMusicAudio = getAudioClip(getDocumentBase(), "audio/Music.mid");
    explAudio = getAudioClip(getDocumentBase(), "audio/Explosion.wav");
    gameOverAudio = getAudioClip(getDocumentBase(), "audio/GameOver.wav");
    explosionSrcImg = getImage(getDocumentBase(), "pic/explosion.gif");
    myTankSrcImg = getImage(getDocumentBase(), "pic/Tank.png");
    enemyTankSrcImg = getImage(getDocumentBase(), "pic/ETank.png");
    shellSrcImg = getImage(getDocumentBase(), "pic/Shell.png");
    MT.addImage(explosionSrcImg, 0);
    MT.addImage(myTankSrcImg, 0);
    MT.addImage(enemyTankSrcImg, 0);
    MT.addImage(shellSrcImg, 0);
    try {
      MT.waitForAll();
    }
    catch (InterruptedException E) {}
      explosionImg = GetClipImage.getImages(explosionSrcImg, 8, 34, 33);
      myTankImg = GetClipImage.getImages(myTankSrcImg, 4, 45, 45);
      enemyTankImg = GetClipImage.getImages(enemyTankSrcImg, 4, 45, 45);
      shellImg = GetClipImage.getImages(shellSrcImg, 2, 10, 10);
      myTankWidth = myTankSrcImg.getWidth(this) / 4;
      myTankHeight = myTankSrcImg.getHeight(this);
      enemyTankWidth = enemyTankSrcImg.getWidth(this) / 4;
      enemyTankHeight = enemyTankSrcImg.getHeight(this);
      myTankX = (this.getWidth() - myTankWidth) / 2;
      myTankY = (this.getHeight() - myTankHeight);
      bufferImage = this.createImage(this.getWidth(), this.getHeight());
      bufferGraphic = bufferImage.getGraphics();
      this.setFocusable(true);
      this.resize(this.getWidth(), this.getHeight());
      rand = new Random();
      MyShell = new ShellSprite(shellImg[0], 0, 20, this);
      MyShell.setWidthHeight(shellSrcImg.getWidth(this) / 2,
                             shellSrcImg.getHeight(this) / 2);
      explosion = new Explosion(explosionImg, this);
      myTankSprite = new PlayTankSprite(myTankImg, myTankX, myTankY, MyShell, this);
      myTankSprite.setWidthHeight(myTankWidth, myTankHeight);
      enemyTank = new EnemyTankSprite[EnemyNum];
      enemyShell = new ShellSprite[EnemyNum];
      createNewEnemyTank();
    }
    public void start() {
      threadTank = new TankThread(this, myTankSprite, enemyTank, MyShell,
                                  enemyShell, explosion);
      threadTank.start();
    }
    public void stop() {
      threadTank = null;
    }
    public void createNewEnemyTank() {
      for (int i = 0; i < EnemyNum; i++) {
        enemyTankX = rand.nextInt(10000) % (this.getWidth() - enemyTankWidth);
        enemyTankY = rand.nextInt(10000) % (this.getHeight() - enemyTankHeight);
        enemyShell[i] = new ShellSprite(shellImg[1], 0, 5, this);
        enemyShell[i].setWidthHeight(shellSrcImg.getWidth(this) / 2,
                                     shellSrcImg.getHeight(this) / 2);
        enemyShell[i].setVisible(true);
        enemyShell[i].setActive(true);
        enemyTank[i] = new EnemyTankSprite(enemyTankImg, enemyTankX, enemyTankY,
                                           enemyShell[i], this);
        enemyTank[i].setWidthHeight(enemyTankWidth, enemyTankHeight);
        enemyTank[i].setTankDirection(rand.nextInt(12) % 4);
        enemyTank[i].setVisible(true);
        enemyTank[i].setActive(true);
      }
    }
    public void recreateEnemyTank() {
      if (destroyEnemyNum == EnemyNum) {
        destroyEnemyNum = 0;
        createNewEnemyTank();
      }
    }
    public void paint(Graphics g) {
      bufferGraphic.clearRect(0, 0, this.getWidth(), this.getHeight());
      recreateEnemyTank();
      for (int i = 0; i < EnemyNum; i++) {
        if (enemyTank[i].visible == true) {
          enemyTank[i].drawSprite(bufferGraphic, enemyTank[i].getTankDirection());
          enemyShell[i].drawSprite(bufferGraphic);
          int k = rand.nextInt(10000);
          int d = rand.nextInt(12) % 4;
          if (k % 2 != 0 && k < 30) {
            enemyTank[i].setTankDirection(d);
          }
          if (myTankSprite.isCollided(enemyTank[i])){
            setExplosionPosition(enemyTank[i]);
            explosion.setVisible(true);
            enemyTank[i].setActive(false);
            enemyTank[i].setVisible(false);
            destroyEnemyNum = destroyEnemyNum + 1;
          }
            if (MyShell.isCollided(enemyTank[i])) {
              setExplosionPosition(enemyTank[i]);
              explosion.setVisible(true);
              enemyTank[i].setActive(false);
              enemyTank[i].setVisible(false);
              MyShell.setActive(false);
              MyShell.setVisible(false);
              destroyEnemyNum = destroyEnemyNum + 1;
            }
          if (enemyShell[i].isCollided(myTankSprite)) {
              setExplosionPosition(myTankSprite);
              explosion.setVisible(true);
            }
          }
        }
        myTankSprite.drawSprite(bufferGraphic, myTankSprite.getTankDirection());
        explosion.drawSprite(bufferGraphic);
        MyShell.drawSprite(bufferGraphic);
        g.drawImage(bufferImage, 0, 0, this);
      }
      public void setExplosionPosition(AbstractSprite sprite) {
        int dir = 0;
        if (sprite instanceof EnemyTankSprite) {
          dir = ( (EnemyTankSprite) sprite).getTankDirection();
        }
        if (sprite instanceof PlayTankSprite) {
          dir = ( (PlayTankSprite) sprite).getTankDirection();
        }
        switch (dir) {
          case 0:
          case 1:
            explosion.setPos(sprite.getX() + sprite.getWidth() / 2,
                             sprite.getY() + sprite.getHeight() / 2);
            break;
          case 2:
          case 3:
            explosion.setPos(sprite.getX() + sprite.getHeight() / 2,
                             sprite.getY() + sprite.getWidth() / 2);
        }
      }
      public void update(Graphics g) {
        paint(g);
      }
    }