't2', 't3', 't4', 't5', 't6', 't7'],
maximumLevel: 18,
minimumLevel: 1,
credit: 'Tianditu...format: 'tiles',
tileMatrixSetID: 'w',
maximumLevel: 18,
credit: new Cesium.Credit('© Tianditu...t0', 't1', 't2', 't3', 't4', 't5', 't6', 't7'],
maximumLevel: 18,
minimumLevel: 1,
credit: 'Tianditu...format: 'tiles',
tileMatrixSetID: 'w',
maximumLevel: 18,
credit: new Cesium.Credit('© Tianditu...', 'http://www.tianditu.gov.cn/')
});
var index = 0;
imageLayers.addImageryProvider(tdtWebMapTile,index