1. 首先，声明一个2个大小的sprite数组

class GameScreen : public cocos2d::Layer{public:    ...    cocos2d::Sprite *backgroundSpriteArray[2];};

2. 完成初始化，1张图片用于当前显示，另1张用于滚动到下一张

bool GameScreen::init(){    //    // 1. super init first    if ( !Layer::init() )    {        return false;    }        Size visibleSize = Director::getInstance()->getVisibleSize();    Point origin = Director::getInstance()->getVisibleOrigin();        ...        for (int i = 0; i < 2; i ++)    {        backgroundSpriteArray[i] = Sprite::create("GameScreen/Game_Screen_Background.png");        backgroundSpriteArray[i]->setPosition(Point((visibleSize.width / 2), (-1 * visibleSize.height * i) + (visibleSize.height / 2)));        this->addChild(backgroundSpriteArray[i], -2);    }    ...}

 

3. 声明update方法表示每帧的更新

class GameScreen : public cocos2d::Layer{public:    ...    void update(float dt);};

4. 实现update方法

void GameScreen::update(float dt){    Size visibleSize = Director::getInstance()->getVisibleSize();    Point origin = Director::getInstance()->getVisibleOrigin();    for (int i = 0; i < 2; i ++)    {        if (backgroundSpriteArray[i]->getPosition().y >= visibleSize.height + (visibleSize.height / 2) -1)        {            backgroundSpriteArray[i]->setPosition(Point((visibleSize.width / 2) + origin.x, (-1 * visibleSize.height) + (visibleSize.height / 2)));        }    }        for (int i = 0; i < 2; i ++)    {        backgroundSpriteArray[i]->setPosition(Point(backgroundSpriteArray[i]->getPosition().x, backgroundSpriteArray[i]->getPosition().y + (0.75 * visibleSize.height * dt)));    }        ...}

 

5. 触发默认的update方法

bool GameScreen::init(){    ...    this->scheduleUpdate();    ...}