Cesium 获取BBOX
const getBBOX = (cartesian: Cesium.Cartesian3) => {
let cartographic = Cesium.Cartographic.fromCartesian(cartesian);
let lon = Cesium.Math.toDegrees(cartographic.longitude);
let lat = Cesium.Math.toDegrees(cartographic.latitude);
const width_distance =
lon + (0.5 * 360) / Math.pow(2, 18) - (lon - (0.5 * 360) / Math.pow(2, 18));
const height_distance =
lat + (0.5 * 360) / Math.pow(2, 18) - (lat - (0.5 * 360) / Math.pow(2, 18));
const left = lon - 0.5 * width_distance;
const bottom = lat - 0.5 * height_distance;
const right = lon + 0.5 * width_distance;
const top = lat + 0.5 * height_distance;
const BBOX = left + ',' + bottom + ',' + right + ',' + top;
return BBOX;
};
