Display line that crosses 180th meridian
Draw a line across the 180th meridian using a GeoJSON source.
<!DOCTYPE html><html><head><meta charset="utf-8" /><title>Display line that crosses 180th meridian</title><meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" /><script src="https://cdn.jsdelivr.net/npm/@goongmaps/goong-js@1.0.9/dist/goong-js.js"></script><link href="https://cdn.jsdelivr.net/npm/@goongmaps/goong-js@1.0.9/dist/goong-js.css" rel="stylesheet" /><style> body { margin: 0; padding: 0; } #map { position: absolute; top: 0; bottom: 0; width: 100%; }</style></head><body><div id="map"></div><script>goongjs.accessToken = '8qzxZAuxcsctSlmOszInchP1A5GrmRBHJwCBCjO6';var map = new goongjs.Map({container: 'map',style: 'https://tiles.goong.io/assets/goong_map_web.json',center: [-41.62667, 26.11598],zoom: 0}); map.on('load', function () {map.addLayer({'id': 'route','type': 'line','source': {'type': 'geojson','data': {'type': 'Feature','properties': {},'geometry': createGeometry(false)}},'layout': { 'line-cap': 'round' },'paint': {'line-color': '#007296','line-width': 4}}); map.addLayer({'id': 'route-label','type': 'symbol','source': 'route','layout': {'symbol-placement': 'line-center','text-field': 'Crosses the world'}}); map.addLayer({'id': 'route-two','type': 'line','source': {'type': 'geojson','data': {'type': 'Feature','properties': {},'geometry': createGeometry(true)}},'layout': { 'line-cap': 'round' },'paint': {'line-color': '#F06317','line-width': 4}}); map.addLayer({'id': 'route-two-label','type': 'symbol','source': 'route-two','layout': {'symbol-placement': 'line-center','text-field': 'Crosses 180th meridian'}}); function createGeometry(doesCrossAntimeridian) {var geometry = {'type': 'LineString','coordinates': [[-72.42187, -16.59408],[140.27343, 35.67514]]}; // To draw a line across the 180th meridian,// if the longitude of the second point minus// the longitude of original (or previous) point is >= 180,// subtract 360 from the longitude of the second point.// If it is less than 180, add 360 to the second point. if (doesCrossAntimeridian) {var startLng = geometry.coordinates[0][0];var endLng = geometry.coordinates[1][0]; if (endLng - startLng >= 180) {geometry.coordinates[1][0] -= 360;} else if (endLng - startLng < 180) {geometry.coordinates[1][0] += 360;}} return geometry;}});</script> </body></html>