cocos2d-x v3.6 使用TMXLayer::getTiles遍历瓦片地图块

	this->_map = TMXTiledMap::create(tmxFile);
	this->_barriers = this->_map->getLayer("barriers");
	this->_states->setVisible(false);//如果直接在editor中设置invisible, getLayer会返回nullptr
	// find
	auto layerSize = this->_states->getLayerSize();
	auto tiles = this->_barriers->getTiles();
	auto tilesEnd = tiles + static_cast<uint32_t>(layerSize.width * layerSize.height);
	for (; tiles < tilesEnd; ++tiles) {
		if (*tiles != 0) {
			auto properties = this->_map->getPropertiesForGID(*tiles).asValueMap();
			if (!properties.empty()) {
				if (properties["property_name"].asString() == "1") {
					break;
				}
			}
		} //if
	}	this->_map = TMXTiledMap::create(tmxFile);