Example of tracks recorded from multiple paraglider flights on the same day, read from an IGC file.
The five tracks contain a total of 49,707 unique coordinates. Zoom in to see more detail. The background layer is from OpenCycleMap.
import Feature from 'ol/Feature.js';
import IGC from 'ol/format/IGC.js';
import Map from 'ol/Map.js';
import OSM, {ATTRIBUTION} from 'ol/source/OSM.js';
import VectorSource from 'ol/source/Vector.js';
import View from 'ol/View.js';
import {Circle as CircleStyle, Fill, Stroke, Style} from 'ol/style.js';
import {LineString, Point} from 'ol/geom.js';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer.js';
import {getVectorContext} from 'ol/render.js';
const colors = {
'Clement Latour': 'rgba(0, 0, 255, 0.7)',
'Damien de Baesnt': 'rgba(0, 215, 255, 0.7)',
'Sylvain Dhonneur': 'rgba(0, 165, 255, 0.7)',
'Tom Payne': 'rgba(0, 255, 255, 0.7)',
'Ulrich Prinz': 'rgba(0, 215, 255, 0.7)',
};
const styleCache = {};
const styleFunction = function (feature) {
const color = colors[feature.get('PLT')];
let style = styleCache[color];
if (!style) {
style = new Style({
stroke: new Stroke({
color: color,
width: 3,
}),
});
styleCache[color] = style;
}
return style;
};
const vectorSource = new VectorSource();
const igcUrls = [
'data/igc/Clement-Latour.igc',
'data/igc/Damien-de-Baenst.igc',
'data/igc/Sylvain-Dhonneur.igc',
'data/igc/Tom-Payne.igc',
'data/igc/Ulrich-Prinz.igc',
];
function get(url, callback) {
const client = new XMLHttpRequest();
client.open('GET', url);
client.onload = function () {
callback(client.responseText);
};
client.send();
}
const igcFormat = new IGC();
for (let i = 0; i < igcUrls.length; ++i) {
get(igcUrls[i], function (data) {
const features = igcFormat.readFeatures(data, {
featureProjection: 'EPSG:3857',
});
vectorSource.addFeatures(features);
});
}
const time = {
start: Infinity,
stop: -Infinity,
duration: 0,
};
vectorSource.on('addfeature', function (event) {
const geometry = event.feature.getGeometry();
time.start = Math.min(time.start, geometry.getFirstCoordinate()[2]);
time.stop = Math.max(time.stop, geometry.getLastCoordinate()[2]);
time.duration = time.stop - time.start;
});
const vectorLayer = new VectorLayer({
source: vectorSource,
style: styleFunction,
});
const map = new Map({
layers: [
new TileLayer({
source: new OSM({
attributions: [
'All maps © <a href="https://www.opencyclemap.org/">OpenCycleMap</a>',
ATTRIBUTION,
],
url:
'https://{a-c}.tile.thunderforest.com/cycle/{z}/{x}/{y}.png' +
'?apikey=Your API key from https://www.thunderforest.com/docs/apikeys/ here',
}),
}),
vectorLayer,
],
target: 'map',
view: new View({
center: [703365.7089403362, 5714629.865071137],
zoom: 9,
}),
});
let point = null;
let line = null;
const displaySnap = function (coordinate) {
const closestFeature = vectorSource.getClosestFeatureToCoordinate(coordinate);
const info = document.getElementById('info');
if (closestFeature === null) {
point = null;
line = null;
info.innerHTML = ' ';
} else {
const geometry = closestFeature.getGeometry();
const closestPoint = geometry.getClosestPoint(coordinate);
if (point === null) {
point = new Point(closestPoint);
} else {
point.setCoordinates(closestPoint);
}
const date = new Date(closestPoint[2] * 1000);
info.innerHTML =
closestFeature.get('PLT') + ' (' + date.toUTCString() + ')';
const coordinates = [coordinate, [closestPoint[0], closestPoint[1]]];
if (line === null) {
line = new LineString(coordinates);
} else {
line.setCoordinates(coordinates);
}
}
map.render();
};
map.on('pointermove', function (evt) {
if (evt.dragging) {
return;
}
const coordinate = map.getEventCoordinate(evt.originalEvent);
displaySnap(coordinate);
});
map.on('click', function (evt) {
displaySnap(evt.coordinate);
});
const stroke = new Stroke({
color: 'rgba(255,0,0,0.9)',
width: 1,
});
const style = new Style({
stroke: stroke,
image: new CircleStyle({
radius: 5,
fill: null,
stroke: stroke,
}),
});
vectorLayer.on('postrender', function (evt) {
const vectorContext = getVectorContext(evt);
vectorContext.setStyle(style);
if (point !== null) {
vectorContext.drawGeometry(point);
}
if (line !== null) {
vectorContext.drawGeometry(line);
}
});
const featureOverlay = new VectorLayer({
source: new VectorSource(),
map: map,
style: new Style({
image: new CircleStyle({
radius: 5,
fill: new Fill({
color: 'rgba(255,0,0,0.9)',
}),
}),
}),
});
const control = document.getElementById('time');
control.addEventListener('input', function () {
const value = parseInt(control.value, 10) / 100;
const m = time.start + time.duration * value;
vectorSource.forEachFeature(function (feature) {
const geometry =
/** @type {import("../src/ol/geom/LineString.js").default} */ (
feature.getGeometry()
);
const coordinate = geometry.getCoordinateAtM(m, true);
let highlight = feature.get('highlight');
if (highlight === undefined) {
highlight = new Feature(new Point(coordinate));
feature.set('highlight', highlight);
featureOverlay.getSource().addFeature(highlight);
} else {
highlight.getGeometry().setCoordinates(coordinate);
}
});
map.render();
});
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>IGC Data</title>
<link rel="stylesheet" href="node_modules/ol/ol.css">
<style>
.map {
width: 100%;
height: 400px;
}
</style>
</head>
<body>
<div id="map" class="map"></div>
<input id="time" type="range" value="0" steps="1" />
<div id="info"> </div>
<script type="module" src="main.js"></script>
</body>
</html>
{
"name": "igc",
"dependencies": {
"ol": "10.3.1"
},
"devDependencies": {
"vite": "^3.2.3"
},
"scripts": {
"start": "vite",
"build": "vite build"
}
}