Java来做马里奥[0]—让精灵再次舞动

记得在红白机（FC）年代，还刚刚上小学的我对马里奥、冒险岛、洛克人、魂斗罗等游戏几乎可说是痴迷，每天放学回家就是想去游戏，就是要通关，就是想和关底论个胜负高低。

许多年过去了，沧海桑田，FC曾经的荣耀早已不再，只留下我们对曾经少年时的点点记忆。即使当时在FC上看上去多么复杂，多么高不可攀的游戏，在当今，即使最普通的程序员都可以轻易实现。

本着向经典学习、向经典致敬的心情，我也准备用Java在PC机再现当年马里奥的风采。

下面我在代码中所演示的，是一个简单的ACT游戏动作及地图构成原型。

Map.java
package org.test.mario;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;

/** *//**
 *

 * Title: LoonFramework
 *

 *

 * Description:地图绘制及描述用类
 *

 *

 * Copyright: Copyright (c) 2008
 *

 *

 * Company: LoonFramework
 *

 *
 * @author chenpeng
 * @email：[email][email protected][/email]
 * @version 0.1
 */
public class Map ...{

    // 在以前的blog文章中我介绍过，游戏开发中通常以数组描述地图
    // 此处1描绘为一个障碍物，0描绘为一个可通行空间
    final static private int[][] map = ...{
            ...{ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
            ...{ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 } };

    // 地面瓦片的宽度
    final static private int TILE_SIZE = 32;

    // 行
    final static private int ROW = 15;

    // 列
    final static private int COL = 20;

    /** *//**
     * 构造函数
     *
     */
    public Map() ...{
    }

    public void draw(Graphics g) ...{
         g.setColor(Color.ORANGE);
        for (int i = 0; i < ROW; i++) ...{
            for (int j = 0; j < COL; j++) ...{
                switch (map[i][j]) ...{
                case 1:
                    g.fillRect(tilesToPixels(j), tilesToPixels(i), TILE_SIZE,
                            TILE_SIZE);
                    break;
                }
            }
        }
    }

    /** *//**
     * 换算角色与地板的撞击，并返回Point用以描述新的x,y
     *
     * @param player
     * @param newX
     * @param newY
     * @return
     */
    public Point getTileHit(Role player, double newX, double newY) ...{
        // 取最小的整数但不能小于自身，用以换算坐标
        newX = Math.ceil(newX);
        newY = Math.ceil(newY);

        double fromX = Math.min(player.getX(), newX);
        double fromY = Math.min(player.getY(), newY);
        double toX = Math.max(player.getX(), newX);
        double toY = Math.max(player.getY(), newY);

        int fromTileX = pixelsToTiles(fromX);
        int fromTileY = pixelsToTiles(fromY);
        int toTileX = pixelsToTiles(toX + Role.WIDTH - 1);
        int toTileY = pixelsToTiles(toY + Role.HEIGHT - 1);

        // 返回Point，用以描述x,y坐标点
        for (int x = fromTileX; x <= toTileX; x++) ...{
            for (int y = fromTileY; y <= toTileY; y++) ...{
                if (x < 0 || x >= COL) ...{
                    return new Point(x, y);
                }
                if (y < 0 || y >= ROW) ...{
                    return new Point(x, y);
                }
                if (map[y][x] == 1) ...{
                    return new Point(x, y);
                }
            }
        }

        return null;
    }

    /** *//**
     * 将Tiles转为Pixels
     *
     * @param pixels
     * @return
     */
    public static int pixelsToTiles(double pixels) ...{
        return (int) Math.floor(pixels / TILE_SIZE);
    }

    /** *//**
     * 将Pixels转为Tiles
     *
     * @param pixels
     * @return
     */
    public static int tilesToPixels(int tiles) ...{
        return tiles * TILE_SIZE;
    }
}

Role.java
package org.test.mario;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;

/** *//**
 *

 * Title: LoonFramework
 *

 *

 * Description:角色描述及绘制用类
 *

 *

 * Copyright: Copyright (c) 2008
 *

 *

 * Company: LoonFramework
 *

 *
 * @author chenpeng
 * @email：[email][email protected][/email]
 * @version 0.1
 */
public class Role ...{

    // 坐标的x,y
    private double _x;

    private double _y;

    // 显示的x,_y
    private double _vx;

    private double _vy;

    // 是否在平地
    private boolean isFlat;

    // 自定义的地图描述类
    private Map _map;

    // 角色宽
    final static public int WIDTH = 32;

    // 角色高
    final static public int HEIGHT = 32;

    // 移动速度
    final static public int SPEED = 6;

    // 跳越速度
    final static public int JUMP_SPEED = 25;

    /** *//**
     * 构造函数，注入初始的角色x,y及map
     *
     * @param _x
     * @param _y
     * @param _map
     */
    public Role(double x, double _y, Map _map) ...{
        this._x = x;
        this._y = _y;
        this._map = _map;
        _vx = 0;
        _vy = 0;
        isFlat = false;
    }

    /** *//**
     * 停止动作
     *
     */
    public void stop() ...{
        _vx = 0;
    }

    /** *//**
     * 向左
     *
     */
    public void left() ...{
        _vx = -SPEED;
    }

    /** *//**
     * 向右
     *
     */
    public void right() ...{
        _vx = SPEED;
    }

    /** *//**
     * 跳越动作
     *
     */
    public void jump() ...{
        // 当角色立于平地时
        if (isFlat) ...{
            _vy = -JUMP_SPEED;
            isFlat = false;
        }
    }

    /** *//**
     * 变更位置
     *
     */
    public void update() ...{
        // 加入偏差值
        _vy += 1.0;

        // 获得新的newX
        double newX = _x + _vx;

        // 获得地板x,_y
        Point tile = _map.getTileHit(this, newX, _y);
        // 不存在时则默认为newX
        if (tile == null) ...{
            _x = newX;
        } else ...{
            if (_vx > 0) ...{
                _x = Map.tilesToPixels(tile.x) - WIDTH;
            } else if (_vx < 0) ...{
                _x = Map.tilesToPixels(tile.x + 1);
            }
            _vx = 0;
        }

        double newY = _y + _vy;

        tile = _map.getTileHit(this, _x, newY);
        if (tile == null) ...{
            _y = newY;
            isFlat = false;
        } else ...{
            if (_vy > 0) ...{
                _y = Map.tilesToPixels(tile.y) - HEIGHT;
                _vy = 0;
                isFlat = true;
            } else if (_vy < 0) ...{
                _y = Map.tilesToPixels(tile.y + 1);
                _vy = 0;
            }
        }
    }

    /** *//**
     * 将角色绘制于指定Graphics上
     *
     * @param g
     */
    public void draw(Graphics g) ...{
        // 目前以一个红色方块代替
        g.setColor(Color.RED);
        g.fillRect((int) _x, (int) _y, WIDTH, HEIGHT);
    }

    public double getX() ...{
        return _x;
    }

    public double getY() ...{
        return _y;
    }

}

启动类：Main.java
package org.test.mario;

import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Panel;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import org.loon.framework.game.p_w_picpath.Bitmap;

/** *//**
 *

 * Title: LoonFramework
 *

 *

 * Description:
 *

 *

 * Copyright: Copyright (c) 2008
 *

 *

 * Company: LoonFramework
 *

 *
 * @author chenpeng
 * @email：[email][email protected][/email]
 * @version 0.1
 */
public class Main extends Panel implements Runnable, KeyListener ...{

    /** *//**
     *
     */
    private static final long serialVersionUID = 1L;

    public static final int _WIDTH = 640;

    public static final int _HEIGHT = 480;

    private Map _map;

    private Role _role;

    private Thread _sleep;

    private Image _screen = null;

    private Graphics _graphics = null;

    // 方向控制，由于是自然落体所以没有down
    private boolean LEFT;

    private boolean RIGHT;

    private boolean UP;

    public Main() ...{
        setSize(_WIDTH, _HEIGHT);
        setFocusable(true);
        _screen = new Bitmap(_WIDTH, _HEIGHT).getImage();
        _graphics = _screen.getGraphics();
        _map = new Map();
        
        _role = new Role(100, 32, _map);

        // 监听窗体
        addKeyListener(this);

        // 启动线程
        _sleep = new Thread(this);
        _sleep.start();
    }

    /** *//**
     * 运行
     */
    public void run() ...{
        while (true) ...{
            //改变方向
            if (LEFT) ...{
                _role.left();
            } else if (RIGHT) ...{
                _role.right();
            } else ...{
                _role.stop();
            }
            if (UP) ...{
                _role.jump();
            }
            _role.update();
            repaint();
            try ...{
                Thread.sleep(20);
            } catch (InterruptedException e) ...{
                e.printStackTrace();
            }
        }
    }

    public void update(Graphics g) ...{
        paint(g);
    }

    public void paint(Graphics g) ...{
        _graphics.setColor(Color.BLACK);
        _graphics.fillRect(0, 0, _WIDTH, _HEIGHT);
        _map.draw(_graphics);
        _role.draw(_graphics);
        g.drawImage(_screen, 0, 0, null);
    }

    public void keyPressed(KeyEvent e) ...{
        int key = e.getKeyCode();
        if (key == KeyEvent.VK_LEFT) ...{
            LEFT = true;
        }
        if (key == KeyEvent.VK_RIGHT) ...{
            RIGHT = true;
        }
        if (key == KeyEvent.VK_UP) ...{
            UP = true;
        }
    }

    public void keyReleased(KeyEvent e) ...{
        int key = e.getKeyCode();
        if (key == KeyEvent.VK_LEFT) ...{
            LEFT = false;
        }
        if (key == KeyEvent.VK_RIGHT) ...{
            RIGHT = false;
        }
        if (key == KeyEvent.VK_UP) ...{
            UP = false;
        }
    }

    public void keyTyped(KeyEvent e) ...{
    }

    public static void main(String[] args) ...{
        Frame frame = new Frame();
        frame.setTitle("Java来做马里奥（1）—让精灵舞动");
        frame.setSize(_WIDTH, _HEIGHT);
        frame.setResizable(false);
        frame.setLocationRelativeTo(null);
        frame.add(new Main());
        frame.setVisible(true);
        frame.addWindowListener(new WindowAdapter() ...{
            public void windowClosing(WindowEvent e) ...{
                System.exit(0);
            }
        });
    }

}

运行效果如下图：


现在开始，我会在blog中逐步构建马里奥中的一关，有关心java pc游戏开发者敬请留意。