globe.gl
Version:
UI component for Globe Data Visualization using ThreeJS/WebGL
84 lines (71 loc) • 2.57 kB
HTML
<head>
<style>
body { margin: 0; }
#time-log {
position: absolute;
font-size: 12px;
font-family: sans-serif;
padding: 5px;
border-radius: 3px;
background-color: rgba(200, 200, 200, 0.1);
color: lavender;
bottom: 10px;
right: 10px;
}
</style>
<script src="//cdn.jsdelivr.net/npm/globe.gl"></script>
<!-- <script src="../../dist/globe.gl.js"></script>-->
</head>
<body>
<div id="chart"></div>
<div id="time-log"></div>
<script type="module">
import * as satellite from 'https://esm.sh/satellite.js';
const EARTH_RADIUS_KM = 6371; // km
const TIME_STEP = 3 * 1000; // per frame
const timeLogger = document.getElementById('time-log');
const world = new Globe(document.getElementById('chart'))
.globeImageUrl('//cdn.jsdelivr.net/npm/three-globe/example/img/earth-blue-marble.jpg')
.particleLat('lat')
.particleLng('lng')
.particleAltitude('alt')
.particlesColor(() => 'palegreen');
setTimeout(() => world.pointOfView({ altitude: 3.5 }));
fetch('../datasets/space-track-leo.txt').then(r => r.text()).then(rawData => {
const tleData = rawData.replace(/\r/g, '')
.split(/\n(?=[^12])/)
.filter(d => d)
.map(tle => tle.split('\n'));
const satData = tleData.map(([name, ...tle]) => ({
satrec: satellite.twoline2satrec(...tle),
name: name.trim().replace(/^0 /, '')
}))
// exclude those that can't be propagated
.filter(d => !!satellite.propagate(d.satrec, new Date())?.position);
// time ticker
let time = new Date();
(function frameTicker() {
requestAnimationFrame(frameTicker);
time = new Date(+time + TIME_STEP);
timeLogger.innerText = time.toString();
// Update satellite positions
const gmst = satellite.gstime(time);
satData.forEach(d => {
const eci = satellite.propagate(d.satrec, time);
if (eci?.position) {
const gdPos = satellite.eciToGeodetic(eci.position, gmst);
d.lat = satellite.radiansToDegrees(gdPos.latitude);
d.lng = satellite.radiansToDegrees(gdPos.longitude);
d.alt = gdPos.height / EARTH_RADIUS_KM;
} else {
// explicitly handle invalid position
d.lat = NaN;
d.lng = NaN;
d.alt = NaN;
}
});
world.particlesData([satData.filter(d => !isNaN(d.lat) && !isNaN(d.lng) && !isNaN(d.alt))]);
})();
});
</script>
</body>