tank.java

Tank 手机游戏 J2ME 简单么明了

package pack04;
import javax.microedition.lcdui.game.Sprite;
public class Tank extends Sprite {
    private int speed=2;
    public final static int UP=0;
    public final static int RIGHT=1;
    public final static int DOWN=2;
    public final static int LEFT=3;
    private int currentDirection=RIGHT;
    GameMap map;
    public Tank(GameMap map)
    {
        super(Utility.getImage("/Splash.png"));
        this.defineReferencePixel(6, 6);
        this.map=map;
    }
    private void changeDirection (int direction)
    {
        if(direction ==currentDirection)
            return ;
        currentDirection=direction;
        switch(direction)
        {
            case UP:
            this.setTransform(Sprite.TRANS_ROT270);
            break;
            case DOWN:
            this.setTransform(Sprite.TRANS_ROT90);
            break;
            case LEFT:
                this.setTransform(Sprite.TRANS_ROT180);
            break;
            case RIGHT:
            this.setTransform(Sprite.TRANS_NONE);
            break;
        }
    }

    public boolean tryMove(int direction)
    {
        changeDirection(direction);
        int dx=0,dy=0;
        switch(direction)
        {
            case UP:
                dy = -speed;
                break;
             case RIGHT:
                dx = speed;
                break;
            case DOWN:
                dy = speed;
                break;
           case LEFT:
                dx = -speed;
                break;
        }
        this.move(dx, dy);
        if(map.isOutOfBorder(this))
        {
            this.move(-dx, -dy);
            return false;
        }
        if(this.collidesWith(map, false))
        {
            this.move(-dx, -dy);
            return false;
        }
        return true;
    }
}