背景的滚动

void GamePlayBackgroundLayer::update(float delta){if(!gameSceneContorlLayerInstance->isRunning || gameSceneContorlLayerInstance->isOver)return;CCArray* pArray = getChildren();for(int i = 0;i < pArray->count();i++){CCSprite* pBackground = (CCSprite*)pArray->objectAtIndex(i);pBackground->setPositionX(pBackground->getPositionX() - 1);if(pBackground->getPositionX() + backgroundX < 0){removeChild(pBackground);i--;}}if(pLastBackgroundSprite != NULL && (pLastBackgroundSprite->getPositionX() < 300))createBackground();}