void RenderTextureTest::backCallback(Object* sender)
{
    auto s = new RenderTextureScene();
    s->addChild( backTestCase() );
    Director::getInstance()->replaceScene(s);
    s->release();
} 
void RenderTextureTestDemo::backCallback(CCObject* pSender)
{
    CCScene* s = new RenderTextureScene();
    s->addChild( backTestCase() );
    CCDirector::sharedDirector()->replaceScene(s);
    s->release();
} 
void RenderTextureTest::backCallback(Ref* sender)
{
    auto s = new (std::nothrow) RenderTextureScene();
    s->addChild( backTestCase() );
    Director::getInstance()->replaceScene(s);
    s->release();
}