Files
openlayers/examples/heatmap-earthquakes.js
2018-04-24 09:06:30 -06:00

54 lines
1.4 KiB
JavaScript

import Map from '../src/ol/Map.js';
import View from '../src/ol/View.js';
import KML from '../src/ol/format/KML.js';
import {Heatmap as HeatmapLayer, Tile as TileLayer} from '../src/ol/layer.js';
import Stamen from '../src/ol/source/Stamen.js';
import VectorSource from '../src/ol/source/Vector.js';
const blur = document.getElementById('blur');
const radius = document.getElementById('radius');
const 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.
const name = event.feature.get('name');
const magnitude = parseFloat(name.substr(2));
event.feature.set('weight', magnitude - 5);
});
const raster = new TileLayer({
source: new Stamen({
layer: 'toner'
})
});
const 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));
});