; (function (Cesium) {
    checkSkyScenery(Cesium);
    function add3DTilesData(url, viewer, options) {
        if (viewer.viewerType != "SkyScenery") throw "viewer is error";
        var viewerObj = viewer
        if (url != undefined) {
            if (typeof url != "string") {
                throw "url parameter error"
            }
        } else {
            throw "url cannot be empty"
        }
        if (viewerObj == undefined) {
            viewerObj = Cesium.Viewer.prototype.viewer
        }
        try {
            let option = {
                url: url,
                skipLevelOfDetail: true, //开启跳级加载
                maximumMemoryUsage: 1024, //最大内存占用  推荐显存的一般
                preferLeaves: true,
                maximumScreenSpaceError: 16,
                maximumNumberOfLoadedTiles: 2000,
            }
            option = Object.assign(option, options)
            var tileset = new Cesium.Cesium3DTileset(option);
            viewerObj.scene.primitives.add(tileset);
            return tileset;
        } catch (error) {
            throw "viewer error"
        }
    };
    Cesium.add3DTilesData = add3DTilesData;
}(SkyScenery))