flappy bird游戏源代码揭秘和下载

作者：左文
链接：https://www.zhihu.com/question/22715390/answer/22368482
来源：知乎
著作权归作者所有，转载请联系作者获得授权。

背景：
最近火爆全球的游戏flappy bird让笔者叹为观止，于是花了一天的时间山寨了一个一模一样的游戏，现在把游戏的思路和源码分享出来，代码是基于javascript语言，cocos2d-x游戏引擎，cocos2d-x editor手游开发工具完成的，请读者轻砸；
ps：运行demo必须配置好cocos2d-x editor，暂不支持其他工具；还有demo是跨平台的，可移植运行android，ios，html5移动系统等，csdn博客里会介绍代码如何移植，请持续关注；

Android Apk下载演示：
暂时先移植到android平台
下载地址： http://share.weiyun.com/cac18d8c58d40bf2401b3fdeeb6bcb2f

代码下载：
csdn下载：http://download.csdn.net/detail/touchsnow/6912707
百度云盘：http://pan.baidu.com/s/1pJnWDb9
金山快盘：http://www.kuaipan.cn/file/id_25348935635745384.htm?source=1

代码如何移植到各平台：
Android：http://blog.csdn.net/touchsnow/article/details/19176091
html5: http://blog.makeapp.co/?p=245

效果图：

开发工具：
cocos2dx editor，它是开发跨平台的手机游戏工具，运行window/mac系统上，javascript脚本语言，基于cocos2d-x跨平台游戏引擎, 集合代码编辑，场景设计，动画制作，字体设计，还有粒子，物理系统，地图等等的，而且调试方便，和实时模拟；
cocos2dx editor下载，介绍和教程：http://blog.csdn.net/touchsnow/article/details/19070665；
cocos2dx editor官方博客：http://blog.makeapp.co/?cat=8；

思路和源码：

1 场景设计MainLayer.ccbx，如下图；主要分三层，开始场景、主场景、游戏结束场景，通过显示隐藏控制三个场景的切换。
MainLayer.ccbx代码

<?xml version="1.0" encoding="UTF-8"?>

<Document
        jsControlled="true"
        jsController="MainLayer"
        resolution="default"
        >

    <Resolutions>
        <Resolution centeredOrigin="false" ext="iphone" height="1280" width="720" name="default" scale="1"/>
        <Resolution centeredOrigin="false" ext="iphone" height="720" width="1280" name="default1" scale="1"/>
    </Resolutions>

    <Animations>
        <Animation autoPlay="true"
                   id="0"
                   name="Default Timeline"
                   length="10"
                   chainedId="0"
                   offset="0.0"
                   position="0.0"
                   resolution="30"
                   scale="128">
            <CallbackChannel>
            </CallbackChannel>
            <SoundChannel>
            </SoundChannel>
        </Animation>

    </Animations>
    <Layer
            positionX="0" positionY="0.0"
            sizeType="Percent"
            width="100" height="100"
            anchorPointX="0.5" anchorPointY="0.5" ignoreAnchorPoint="true"
            scaleX="1" scaleY="1"
            >

      <Sprite positionType="LeftBottom" width="720.0" height="1280.0" positionX="0" positionY="0" anchorPointX="0"
                                         anchorPointY="0" src="Resources/bg.png" name="" var="" target="None" scaleX="1" scaleY="1" visible="true"/>
      <LayerColor positionType="LeftBottom" width="720" height="1280" positionX="0" positionY="0" anchorPointX="0"
                  anchorPointY="0" color="#fff2e8ff" visible="false"/>
      <Menu positionType="LeftBottom" width="40" height="40" positionX="356.0" positionY="237.0" anchorPointX="0.5"
              anchorPointY="0.5" scaleX="2.4" scaleY="1.725">
      </Menu>
      <Sprite positionType="LeftBottom" width="840.0" height="281.0" positionX="0" positionY="0" anchorPointX="0"
                                         anchorPointY="0" src="Resources/ground.png" var="ground" target="Doc"/>
      <Node positionType="LeftBottom" width="40" height="40" positionX="800" positionY="250" anchorPointX="0"
            anchorPointY="0" var="hoseNode" target="Doc">
        <Sprite positionType="LeftBottom" width="86.0" height="60.0" positionX="-500" positionY="400" anchorPointX="0.5"
                                         anchorPointY="0.5" src="Resources/flappy_packer.plist/bird3.png" var="test" target="Doc" visible="false"/>
        <Sprite positionType="LeftBottom" width="86.0" height="60.0" positionX="-550" positionY="500" anchorPointX="0.5"
                anchorPointY="0.5" src="Resources/flappy_packer.plist/bird1.png" var="bird" target="Doc" scaleX="1" scaleY="1" rotation="0" visible="true"/>
      </Node>
      <Node positionType="LeftBottom" width="40" height="40" positionX="303.0" positionY="500" anchorPointX="0.5"
            anchorPointY="0.5" var="readyNode" target="Doc" visible="true">
        <Sprite positionType="LeftBottom" width="508.0" height="158.0" positionX="95.0" positionY="584.0" anchorPointX="0.5"
                                         anchorPointY="0.5" src="Resources/flappy_packer.plist/getready.png"/>
        <Sprite positionType="LeftBottom" width="286.0" height="246.0" positionX="73.0" positionY="236.0" anchorPointX="0.5"
                                         anchorPointY="0.5" src="Resources/flappy_packer.plist/click.png"/>
      </Node>
      <Node positionType="LeftBottom" width="40" height="40" positionX="300" positionY="500" anchorPointX="0.5"
            anchorPointY="0.5" var="overNode" target="Doc" visible="true">
        <Sprite positionType="LeftBottom" width="590.0" height="298.0" positionX="72.0" positionY="219.0" anchorPointX="0.5"
                                         anchorPointY="0.5" src="Resources/flappy_packer.plist/base.png">
          <Sprite positionType="LeftBottom" width="508.0" height="158.0" positionX="286.0" positionY="458.0" anchorPointX="0.5"
                                         anchorPointY="0.5" src="Resources/flappy_packer.plist/gameover.png"/>
        </Sprite>
        <Menu positionType="LeftBottom" width="40" height="40" positionX="0" positionY="0" anchorPointX="0.5"
              anchorPointY="0.5">
          <MenuItem positionType="LeftBottom" width="290" height="176" positionX="-65.0" positionY="-92.0" anchorPointX="0.5"
                    anchorPointY="0.5" normalImage="Resources/flappy_packer.plist/start.png" target="Doc" onClick="onStartClicked"/>
          <MenuItem positionType="LeftBottom" width="290" height="176" positionX="230.0" positionY="-92.0" anchorPointX="0.5"
                    anchorPointY="0.5" target="Doc" normalImage="Resources/flappy_packer.plist/grade.png" onClick="onGradeClicked"/>
        </Menu>
      </Node>
    </Layer>


</Document>

2 代码编写MainLayer.js
首先，小鸟在向前飞，其实是底部的路和水管在向左移动，相对的你就感觉小鸟在向右飞了；路循环移动代码：

MainLayer.prototype.groundRun = function ()
{
    var action1 = cc.MoveTo.create(0.5, cc.p(-120, 0));
    var action2 = cc.MoveTo.create(0, cc.p(0, 0));
    var action = cc.Sequence.create(action1, action2);
    this.ground.runAction(cc.RepeatForever.create(action));
}

初始化高低不同的水管，每一关卡都由上下两水管和空隙组成。总长度相同，空隙也一定，随机取下面水管的长度，就形成错落有致的水管关卡；

MainLayer.prototype.newHose = function (num)
{
    var hoseHeight = 830;
    var acrossHeight = 300;
    var downHeight = 100 + getRandom(400);
    var upHeight = 1100 - downHeight - acrossHeight;

    var hoseX = 400 * num;

    var HoseName = FP_MAIN_TEXTURE.HOSE;
    var ccSpriteDown = cc.Sprite.createWithSpriteFrameName(HoseName[0]);
    ccSpriteDown.setZOrder(1);
    ccSpriteDown.setAnchorPoint(cc.p(0, 0));
    ccSpriteDown.setPosition(cc.p(hoseX, 0));
    ccSpriteDown.setScaleY(downHeight / hoseHeight);

    var ccSpriteUp = cc.Sprite.createWithSpriteFrameName(HoseName[1]);
    ccSpriteUp.setZOrder(1);
    ccSpriteUp.setAnchorPoint(cc.p(0, 0));
    ccSpriteUp.setPosition(cc.p(hoseX, downHeight + acrossHeight));
    ccSpriteUp.setScaleY(upHeight / hoseHeight);

    this.hoseNode.addChild(ccSpriteDown);
    this.hoseNode.addChild(ccSpriteUp);
    this.hoseSpriteList.push(ccSpriteDown);
    this.hoseSpriteList.push(ccSpriteUp);
    return null;
}

一开始进入游戏让底部路不断移动，初始化水管，显示准备游戏场景；

MainLayer.prototype.onEnter = function ()
{
    cc.AnimationCache.getInstance().addAnimations("Resources/flappy_frame.plist");
    this.groundRun();
    this.ground.setZOrder(10);
    this.birdReadyAction();
    this.bird.setZOrder(20);
    this.readyNode.setVisible(true);
    this.overNode.setVisible(false);

    for (var i = 0; i < 30; i++) {
        this.newHose(i);
    }
}

点击屏幕，小鸟向上飞60dp,然后更快的速度下落（移动动画），同时闪动翅膀（帧动画）；

MainLayer.prototype.birdRiseAction = function ()
{
    var riseHeight = 60;
    var birdX = this.bird.getPositionX();
    var birdY = this.bird.getPositionY();
    var time = birdY / 600;

    var actionFrame = cc.Animate.create(cc.AnimationCache.getInstance().getAnimation("fly"));
    var flyAction = cc.Repeat.create(actionFrame, 90000);
    var riseAction1 = cc.MoveTo.create(0.2, cc.p(birdX, birdY + riseHeight));
    var riseAction2 = cc.RotateTo.create(0, -30);
    var riseAction = cc.Spawn.create(riseAction1, riseAction2);
    var fallAction1 = cc.MoveTo.create(time, cc.p(birdX, 50));
    var fallAction2 = cc.Sequence.create(cc.DelayTime.create(time / 6), cc.RotateTo.create(0, 30));
    var fallAction = cc.Spawn.create(fallAction1, fallAction2);

    this.bird.stopAllActions();
    this.bird.runAction(cc.Spawn.create(
            cc.Sequence.create(riseAction, cc.DelayTime.create(0.1), fallAction),
            flyAction)
    );
}

检测碰撞，如果小鸟碰到地面和水管，发生碰撞，这里碰撞直接用cocos2d-x 里面的图片和图片交叉函数 cc.rectIntersectsRect；

MainLayer.prototype.checkCollision = function ()
{
    if (this.bird.getPositionY() < 60) {
        cc.log("floor");
        this.birdFallAction();
        return;
    }
    for (var i = 0; i < this.hoseSpriteList.length; i++) {
        var hose = this.hoseSpriteList[i];
        if (!this.isInScreen(hose)) {
            // continue;
        }

        if (cc.rectIntersectsRect(hose.getBoundingBox(), this.bird.getBoundingBox())) {
            cc.log("hose positionX==" + hose.getBoundingBox().x);
            cc.log("this.bird positionX==" + this.bird.getBoundingBox().x);
            cc.log("i==" + i);
            cc.log("birdFallAction");
            this.birdFallAction();
            return;
        }
    }
}

碰撞后，小鸟先下落，游戏结束场景显示；

MainLayer.prototype.birdFallAction = function ()
{
    this.gameMode = OVER;
    this.bird.stopAllActions();
    this.ground.stopAllActions();
    var birdX = this.bird.getPositionX();
    var birdY = this.bird.getPositionY();
    var time = birdY / 2000;
    this.bird.runAction(cc.Sequence.create(
            cc.DelayTime.create(0.1),
            cc.Spawn.create(cc.RotateTo.create(time, 90), cc.MoveTo.create(time, cc.p(birdX, 50))))
    );
    this.overNode.setVisible(true);
}