Files
openlayers/examples/layer-clipping-vector.js

47 lines
1.2 KiB
JavaScript

import Map from '../src/ol/Map.js';
import View from '../src/ol/View.js';
import {Tile as TileLayer, Vector as VectorLayer} from '../src/ol/layer.js';
import VectorSource from '../src/ol/source/Vector.js';
import GeoJSON from '../src/ol/format/GeoJSON.js';
import OSM from '../src/ol/source/OSM.js';
import {Fill, Style} from '../src/ol/style.js';
import {getVectorContext} from '../src/ol/render.js';
import {fromLonLat} from '../src/ol/proj.js';
const base = new TileLayer({
source: new OSM()
});
const clipLayer = new VectorLayer({
style: null,
source: new VectorSource({
url:
'./data/geojson/switzerland.geojson',
format: new GeoJSON()
})
});
const style = new Style({
fill: new Fill({
color: 'black'
})
});
base.on('postrender', function(e) {
e.context.globalCompositeOperation = 'destination-in';
const vectorContext = getVectorContext(e);
clipLayer.getSource().forEachFeature(function(feature) {
vectorContext.drawFeature(feature, style);
});
e.context.globalCompositeOperation = 'source-over';
});
const map = new Map({
layers: [base, clipLayer],
target: 'map',
view: new View({
center: fromLonLat([8.23, 46.86]),
zoom: 7
})
});