ball.java

手机弹球游戏源码

/*
 * Copyright (c) 2002, 2003 Sun Microsystems, Inc. All Rights Reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * - Redistribution of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * - Redistribution in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * Neither the name of Sun Microsystems, Inc., 'Java', 'Java'-based
 * names, or the names of contributors may be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * You acknowledge that this software is not designed, licensed or
 * intended for use in the design, construction, operation or maintenance
 * of any nuclear facility. $Id: Ball.java,v 1.3 2003/05/29 22:28:05 wildcard Exp $
 */
package com.sun.j2me.blueprints.jbricks;

import javax.microedition.lcdui.Graphics;

/**
 * This class implements the ball, with its radius,
 * and x and y step size. The ball knows how to draw
 * itself, and every once in a while it will do a
 * subtle, pseudo-random path modification to prevent
 * closed ball paths.
 */
public class Ball extends Sprite {
    private int dx;
    private int dy;
    private int xo;
    private int yo;
    public static final int RADIUS = Math.max(2, Screen.width / 55);
    private ThreeDColor color;
    private ThreeDColor brighter;
    private ThreeDColor darker;
    private int counter;
    private int offset;

    public Ball(int x, int y, int dx, int dy) {
        moveTo(x, y);
        setSteps(dx, dy);

        offset = 0;
        width = 2 * RADIUS;
        height = 2 * RADIUS;
        this.dx = dx;
        this.dy = dy;
        xo = yo = 0;
        color = ThreeDColor.red;
        brighter = color.brighter();
        darker = color.darker();
    }

    public void setSteps(int dx, int dy) {
        this.dx = dx;
        this.dy = dy;
    } 

    public int getXStep() {
        return dx;
    } 

    public int getYStep() {
        return dy;
    } 

    public void move() {
        x = x + dx + xo;
        y = y + dy + yo;
        xo = yo = 0;
    } 

    public void bounceHorizontal() {
        dx = -dx;

        if (Util.getRandomInt(0, 1000) < 70) {
            xo = dx < 0 ? -1 : 1;
        } 
    } 

    public void bounceVertical() {
        dy = -dy;

        if (Util.getRandomInt(0, 1000) < 70) {
            yo = dy < 0 ? -1 : 1;
        } 
    } 

    public void bounce(Sprite other) {
        int cx, cy;

        cx = getCenterX();
        cy = getCenterY();

        if (dx < 0) {
            if (cy >= other.y && cy < other.y + other.height 
                    && x < other.x + other.width) {
                dx = Math.abs(dx);
            } 
        } else {
            if (cy >= other.y && cy < other.y + other.height 
                    && x + width >= other.x) {
                dx = -Math.abs(dx);
            } 
        } 

        if (dy < 0) {
            if (cx >= other.x && cx < other.x + other.width 
                    && y < other.y + other.height) {
                dy = Math.abs(dy);
            } 
        } else {
            if (cx >= other.x && cx < other.x + other.width 
                    && y + height >= other.y) {
                dy = -Math.abs(dy);
            } 
        } 

        if (Util.getRandomInt(0, 1000) < 70) {
            xo = dx < 0 ? -1 : 1;
        } 

        if (Util.getRandomInt(0, 1000) < 70) {
            yo = dy < 0 ? -1 : 1;
        } 
    } 

    public void paintShadow(Graphics g) {
        g.setColor(ThreeDColor.black.getRGB());
        g.fillArc(x + shadow, y + shadow, width, height, 0, 360);
    } 

    public void paint(Graphics g) {
        if (++counter == 6) {
            counter = 0;
            offset = 1 - offset;
        } 

        g.setColor(color.getRGB());
        g.fillArc(x, y, width, height, 0, 360);
        g.setColor(brighter.getRGB());
        g.drawArc(x + 2, y + 2, width - 4, height - 4, 180 + offset, -90);
        g.setColor(darker.getRGB());
        g.drawArc(x, y, width, height, 0, -90);
    } 

}