slugsscreen.java

这是我编写的第一个J2ME程序

/*
 * 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: SlugsScreen.java,v 1.2 2003/05/29 22:39:01 wildcard Exp $
 */
package com.sun.j2me.blueprints.slugs.client;

import com.sun.j2me.blueprints.slugs.shared.*;
import com.sun.j2me.blueprints.slugs.shared.Item;
import javax.microedition.lcdui.*;

/**
 * Client visualization component for the slugs game
 */
public class SlugsScreen extends Screen implements PlayerActions {
    // so we don't have to use raw hex
    // numbers to indicate colors
    private static final int white = 0xffffff;
    private static final int black = 0x000000;
    private static final int blue = 0x0000ff;
    private static final int red = 0xff0000;
    private static final int orange = 0xffc800;
    private static final int yellow = 0xffff00;
    private static final int green = 0x00ff00;
    private static final int grass_green = 0x00c000;
    private static final int gray = 0x808080;
    private static final int purple = 0x8000c0;
    private static final int pink = 0xffafaf;
    private static final int lightGray = 0xc0c0c0;
    private static final int darkGray = 0x404040;
    // cell image patterns for use by pixelator
    private static final String[] IMG_PATTERN = {
        "" + "gGgGg" + "!GG!!" + "G!GGG" + "GGG!G" + "gG!Gg", 
        "" + "rrgrr" + "rgbgr" + "gbbbg" + "rgbgr" + "rrgrr", 
        "" + "rrgrr" + "rgygr" + "gyyyg" + "rgygr" + "rrgrr", 
        "" + "gyyyg" + "yXyXy" + "yyyyy" + "yXXXy" + "gyyyg", 
        "" + "####B" + "#gggB" + "#gggB" + "#gggB" + "#BBBB", 
        "" + "@@@@Y" + "@gggY" + "@gggY" + "@gggY" + "@YYYY", 
        "" + "ggggg" + "ggggg" + "ggggg" + "ggggg" + "ggggg", 
        "" + "gnnng" + "NnNNN" + "NnNnN" + "NnnnN" + "gNNNg", 
        "" + "ggrgg" + "grrrg" + "grrrg" + "ggrgg" + "grgrg", 
        "" + "ggggg" + "g##Bg" + "g#bBg" + "g#BBg" + "ggggg", 
        "" + "ggggg" + "g@@Yg" + "g@yYg" + "g@YYg" + "ggggg", 
        "" + "####B" + "#bbbB" + "#bbbB" + "#bbbB" + "#BBBB", 
        "" + "@@@@Y" + "@yyyY" + "@yyyY" + "@yyyY" + "@YYYY", 
        "" + "g...g" + ".g.g." + "g...g" + "g.g.g" + "ggggg", 
        "" + "gnnng" + "ggngg" + "ggngg" + "gaaag" + "ggagg", 
        "" + "YYAKK" + "YYAKK" + "AAAAA" + "KKAYY" + "KKAYY", 
    };
    private static final int BOOSTER = 0;
    private static final int DIG1 = 1;
    private static final int DIG2 = 2;
    private static final int EXTRA_LIFE = 3;
    private static final int FLY1 = 4;
    private static final int FLY2 = 5;
    private static final int GRASS = 6;
    private static final int HOUSE = 7;
    private static final int JET_PACK = 8;
    private static final int PATH1 = 9;
    private static final int PATH2 = 10;
    private static final int PLAYER1 = 11;
    private static final int PLAYER2 = 12;
    private static final int POISON = 13;
    private static final int SHOVEL = 14;
    private static final int WALL = 15;
    private Font font;
    private int font_offset;
    private long last;
    private int fps;
    private int x_offset;
    private int y_offset;
    private int level_width;
    private int level_height;
    private EventClient client;
    private Image buf;
    private Graphics buf_g;
    private Image[] img_list;
    private String life_string;
    private String shovel_string;
    private String jetpack_string;
    private String score_string;
    private int player_id;
    private int lives;
    private String fps_string;
    private boolean showTitle;

    /**
     * Create a new instance of this class
     */
    public SlugsScreen() {
        int i;

        font = Font.getFont(Font.FACE_SYSTEM, Font.STYLE_PLAIN, 
                            Font.SIZE_SMALL);
        font_offset = font.getHeight() + 2;
        fps = 0;
        fps_string = "fps: " + fps;
        showTitle = true;
        buf = Image.createImage(getWidth(), getHeight());
        buf_g = buf.getGraphics();

        buf_g.setColor(black);
        buf_g.fillRect(0, 0, getWidth(), getHeight());

        String color_key = "g!GrybX@Y#BnN.aKA";
        int[] color_value = new int[] {
            0x00c000, 0x78d000, 0x006818, 0xff0000, 0xffff00, 0x0000ff, 
            0x000000, 0xf8f098, 0xf0b000, 0x00ffff, 0x000080, 0xbe7e1e, 
            0x5f3f1e, 0xffffff, 0xc0c0c0, 0x800000, 0x808080
        };

        Pixelator.setColors(color_key, color_value);

        img_list = new Image[IMG_PATTERN.length];

        for (i = 0; i < IMG_PATTERN.length; i++) {
            img_list[i] = Pixelator.createImage(IMG_PATTERN[i], 5);
        } 

        setLives(0);
        setShovels(0);
        setJetpacks(0);
        setScore(0);
    }

    /**
     * Initialize this instance for use with event client 'client'
     * and player id 'player_id'. Since the constructor for this
     * class is called by Class.foName().newInstance() (which
     * requires a no-arg constructor), we need to do the set-up
     * separately.
     */
    public void initialize(EventClient client, int player_id) {
        this.client = client;
        this.player_id = player_id;
    } 

    private void setLives(int lives) {
        this.lives = lives;
        life_string = "" + lives;
    } 

    private void setShovels(int shovels) {
        shovel_string = "" + shovels;
    } 

    private void setJetpacks(int jetpacks) {
        jetpack_string = "" + jetpacks;
    } 

    private void setScore(int score) {
        score_string = "Score: " + score;
    } 

    /**
     * MIDP event key event handling
     */
    public void keyPressed(int keycode) {
        int game_action = getGameAction(keycode);
        int player_action = -1;

        if (true /* lives > 0 */) {
            switch (game_action) {

            case Canvas.UP:
                player_action = PlayerActions.UP;

                break;

            case Canvas.DOWN:
                player_action = PlayerActions.DOWN;

                break;

            case Canvas.LEFT:
                player_action = PlayerActions.LEFT;

                break;

            case Canvas.RIGHT:
                player_action = PlayerActions.RIGHT;

                break;

            default:    // do nothing
            }

            switch (keycode) {

            case Canvas.KEY_NUM1:
                player_action = PlayerActions.JUMP;

                break;

            case Canvas.KEY_NUM3:
                player_action = PlayerActions.DIG;

                break;

            default:    // do nothing
            }

            if (player_action >= 0) {
                client.handleEvent(Message.CLIENT_STATUS, player_action);
            } 
        } 
    } 

    /**
     * MIDP event key event handling
     */
    public void keyReleased(int keycode) {}

    /**
     * Update the game diaply at ('x', 'y') with tag 'tag'
     */
    public void update(int tag, int x, int y) {
        int index, id;

        index = -1;
        id = -1;

        if ((tag & PlayerActions.PLAYER_BITS) != 0) {
            id = tag & 1;
            tag &= ~1;

            if ((tag & BURROW) != 0) {
                index = id == 0 ? DIG1 : DIG2;
            } else if ((tag & FLY) != 0) {
                index = id == 0 ? FLY1 : FLY2;