经常用到的视觉差parallax

auto winSize = Director::getInstance()->getWinSize();
Sprite *bg = Sprite::create("HelloWorld.png");
bg->setAnchorPoint(Vec2(0,0));

Sprite *ball = Sprite::create("sprite.png");
ball->setAnchorPoint(Vec2(0.5,0.5));

Sprite *samll = Sprite::create("sprite.png");
samll->setAnchorPoint(Vec2(0,0));

ParallaxNode *parallaxNode = ParallaxNode::create();
this->addChild(parallaxNode,0,"parall");
parallaxNode->addChild(bg,0,Vec2(0.2,0.2),Vec2(0,0));
parallaxNode->addChild(ball,1,Vec2(1,1),Vec2(winSize.width/2,winSize.height/2));
parallaxNode->addChild(samll,1,Vec2(1,1),Vec2(0,0));
auto e = EventListenerTouchOneByOne::create();
e->onTouchBegan = [bg, ball, samll, parallaxNode](Touch*t, Event*e)
{
return true;
};
e->onTouchMoved = [bg, ball, samll, parallaxNode](Touch*t, Event*e)
{
Vec2 delta = t->getDelta();
parallaxNode->setPosition(parallaxNode->getPosition()+delta);
};
e->onTouchEnded = [bg, ball, samll, parallaxNode](Touch*t, Event*e)
{
log("x= %.2f  y=%.2f",bg->getPositionX(),bg->getPositionY());
log("x= %.2f  y=%.2f", ball->getPositionX(), ball->getPositionY());
log("x= %.2f  y=%.2f", samll->getPositionX(), samll->getPositionY());
log("x= %.2f  y=%.2f", parallaxNode->getPositionX(), parallaxNode->getPositionY());
};
auto es = this->getEventDispatcher();
es->addEventListenerWithSceneGraphPriority(e, this);
return true;

parallax 的   void addChild(Node * child, int z, const Vec2& parallaxRatio, const Vec2& positionOffset);函数

child 为添加的Node 节点 渲染循序 parallaxRatio为相对于parallaxNode 节点比率 如 parallaxNode 移动100 比率为0.5则移动50 positionOffset为开始设定相对于paallaxNode锚点的位子

此函数 常常用在 游戏 地图移动比如： 玛丽奥，魂斗罗等等游戏 可见到