viewer.scene.globe.enableLighting = true; viewer.shadows = true; viewer.terrainShadows = Cesium.ShadowMode.RECEIVE_ONLY; viewer.shadowMap.darkness = 0.5; let time = 0; inter = setInterval(() => { // 改变时间设置光照效果 let date = new Date().getTime() + time; let utc = Cesium.JulianDate.fromDate(new Date(date)); //北京时间 viewer.clockViewModel.currentTime = Cesium.JulianDate.addHours(utc,0, new Cesium.JulianDate()) time = time + 1000 * 60; }, 100); 大佬们, 这样设置, 模型还是没有阴影效果, 该如何实现