cocos2dx视差背景图的实现

Cocos2d-x的CCParallaxNode类可用于实现2d游戏中不同层次地图以不同速率运动的景深效果。具体效果可以查看以下URL：

http://www.56.com/u93/v_OTEzMzE3NjI.html

以下例子中的素材为《IOS5 cocos2d 游戏开发实战》（第2版的），我将objective-c语言描述的例子改成了c++版本的，主要代码如下：

//主角精灵
        CCSprite *qqSprite = CCSprite::create("qq.jpg");
        qqSprite->setPosition(ccp(size.width/2, size.height/2));
        this->addChild(qqSprite, 10);

        //背景地图精灵
        CCSprite *pSprite1 = CCSprite::create("parallax1.png");
        CCSprite *pSprite2 = CCSprite::create("parallax2.png");
        CCSprite *pSprite3 = CCSprite::create("parallax3.png");
        CCSprite *pSprite4 = CCSprite::create("parallax4.png");

        //设置背景地图的锚点
        pSprite1->setAnchorPoint(ccp(0, 1));
        pSprite2->setAnchorPoint(ccp(0, 1));
        pSprite3->setAnchorPoint(ccp(0, 0.5f));
        pSprite4->setAnchorPoint(ccp(0, 0));

        //设置移动速率
        CCPoint topoffset = ccp(0, size.height);
        CCPoint midoffset = ccp(0, size.height / 2);
        CCPoint downoffset = CCPointZero;

        //创建CCParallaxNode节点，并将地图加入该节点
        CCParallaxNode *parallaxnode = CCParallaxNode::create();
        parallaxnode->addChild(pSprite1, 1, ccp(0.8, 0), topoffset);
        parallaxnode->addChild(pSprite2, 2, ccp(1, 0), topoffset);
        parallaxnode->addChild(pSprite3, 4, ccp(3, 0), midoffset);
        parallaxnode->addChild(pSprite4, 3, ccp(4, 0), downoffset);

        this->addChild(parallaxnode, 0, 100);

        //分别向左和向右移动的动作
        CCMoveBy *move1 = CCMoveBy::create(5, ccp(-200, 0));
        CCMoveBy *move2 = CCMoveBy::create(15, ccp(200, 0));

        //运作序列
        CCFiniteTimeAction *sequence = CCSequence::create(move1, move2, NULL);

        //CCSequence放入CCRepeatForever时，需要转化数据类型，否则会提示类型不兼容的错误
        CCRepeatForever *repeat = CCRepeatForever::actionWithAction(static_cast<CCSequence *>(sequence));

        parallaxnode->runAction(sequence);