Files
openlayers/examples/cluster.js
2021-01-25 21:19:15 +08:00

96 lines
2.3 KiB
JavaScript

import Feature from '../src/ol/Feature.js';
import Map from '../src/ol/Map.js';
import Point from '../src/ol/geom/Point.js';
import View from '../src/ol/View.js';
import {
Circle as CircleStyle,
Fill,
Stroke,
Style,
Text,
} from '../src/ol/style.js';
import {Cluster, OSM, Vector as VectorSource} from '../src/ol/source.js';
import {Tile as TileLayer, Vector as VectorLayer} from '../src/ol/layer.js';
import {boundingExtent} from '../src/ol/extent.js';
const distance = document.getElementById('distance');
const count = 20000;
const features = new Array(count);
const e = 4500000;
for (let i = 0; i < count; ++i) {
const coordinates = [2 * e * Math.random() - e, 2 * e * Math.random() - e];
features[i] = new Feature(new Point(coordinates));
}
const source = new VectorSource({
features: features,
});
const clusterSource = new Cluster({
distance: parseInt(distance.value, 10),
source: source,
});
const styleCache = {};
const clusters = new VectorLayer({
source: clusterSource,
style: function (feature) {
const size = feature.get('features').length;
let style = styleCache[size];
if (!style) {
style = new Style({
image: new CircleStyle({
radius: 10,
stroke: new Stroke({
color: '#fff',
}),
fill: new Fill({
color: '#3399CC',
}),
}),
text: new Text({
text: size.toString(),
fill: new Fill({
color: '#fff',
}),
}),
});
styleCache[size] = style;
}
return style;
},
});
const raster = new TileLayer({
source: new OSM(),
});
const map = new Map({
layers: [raster, clusters],
target: 'map',
view: new View({
center: [0, 0],
zoom: 2,
}),
});
distance.addEventListener('input', function () {
clusterSource.setDistance(parseInt(distance.value, 10));
});
map.on('click', (e) => {
clusters.getFeatures(e.pixel).then((clickedFeatures) => {
if (clickedFeatures.length) {
// Get clustered Coordinates
const features = clickedFeatures[0].get('features');
if (features.length > 1) {
const extent = boundingExtent(
features.map((r) => r.getGeometry().getCoordinates())
);
map.getView().fit(extent, {duration: 1000, padding: [50, 50, 50, 50]});
}
}
});
});