Skip to content

Instantly share code, notes, and snippets.

@pbogden

pbogden/README.md

Last active February 15, 2019 22:08
Show Gist options
  • Save pbogden/417b72d388a4a8447ee5940e638787d0 to your computer and use it in GitHub Desktop.
Save pbogden/417b72d388a4a8447ee5940e638787d0 to your computer and use it in GitHub Desktop.
Download ZIP
Leaflet earthquakes
Raw
README.md
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<title>Earthquakes Heatmap</title>
<link rel="stylesheet" href="https://openlayers.org/en/v5.3.0/css/ol.css" type="text/css">
<!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
<script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
<script src="https://openlayers.org/en/v5.3.0/build/ol.js"></script>
<script src="https://openlayers.org/en/v4.6.5/build/ol.js"></script>
</head>
<body>
<div id="map" class="map"></div>
<form>
<label>radius size</label>
<input id="radius" type="range" min="1" max="50" step="1" value="5"/>
<label>blur size</label>
<input id="blur" type="range" min="1" max="50" step="1" value="15"/>
</form>
<script>
import Map from 'ol/Map.js';
import View from 'ol/View.js';
import KML from 'ol/format/KML.js';
import {Heatmap as HeatmapLayer, Tile as TileLayer} from 'ol/layer.js';
import Stamen from 'ol/source/Stamen.js';
import VectorSource from 'ol/source/Vector.js';
var blur = document.getElementById('blur');
var radius = document.getElementById('radius');
var vector = new HeatmapLayer({
source: new VectorSource({
url: 'data/kml/2012_Earthquakes_Mag5.kml',
format: new KML({
extractStyles: false
})
}),
blur: parseInt(blur.value, 10),
radius: parseInt(radius.value, 10)
});
vector.getSource().on('addfeature', function(event) {
// 2012_Earthquakes_Mag5.kml stores the magnitude of each earthquake in a
// standards-violating <magnitude> tag in each Placemark. We extract it from
// the Placemark's name instead.
var name = event.feature.get('name');
var magnitude = parseFloat(name.substr(2));
event.feature.set('weight', magnitude - 5);
});
var raster = new TileLayer({
source: new Stamen({
layer: 'toner'
})
});
var map = new Map({
layers: [raster, vector],
target: 'map',
view: new View({
center: [0, 0],
zoom: 2
})
});
blur.addEventListener('input', function() {
vector.setBlur(parseInt(blur.value, 10));
});
radius.addEventListener('input', function() {
vector.setRadius(parseInt(radius.value, 10));
});
</script>
</body>
</html>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment