import GeoJSON from '../src/ol/format/GeoJSON.js'; import LinearRing from '../src/ol/geom/LinearRing.js'; import Map from '../src/ol/Map.js'; import OSM from '../src/ol/source/OSM.js'; import VectorSource from '../src/ol/source/Vector.js'; import View from '../src/ol/View.js'; import { LineString, MultiLineString, MultiPoint, MultiPolygon, Point, Polygon, } from '../src/ol/geom.js'; import {Tile as TileLayer, Vector as VectorLayer} from '../src/ol/layer.js'; import {fromLonLat} from '../src/ol/proj.js'; const source = new VectorSource(); fetch('data/geojson/roads-seoul.geojson') .then(function (response) { return response.json(); }) .then(function (json) { const format = new GeoJSON(); const features = format.readFeatures(json, { featureProjection: 'EPSG:3857', }); const parser = new jsts.io.OL3Parser(); parser.inject( Point, LineString, LinearRing, Polygon, MultiPoint, MultiLineString, MultiPolygon ); for (let i = 0; i < features.length; i++) { const feature = features[i]; // convert the OpenLayers geometry to a JSTS geometry const jstsGeom = parser.read(feature.getGeometry()); // create a buffer of 40 meters around each line const buffered = jstsGeom.buffer(40); // convert back from JSTS and replace the geometry on the feature feature.setGeometry(parser.write(buffered)); } source.addFeatures(features); }); const vectorLayer = new VectorLayer({ source: source, }); const rasterLayer = new TileLayer({ source: new OSM(), }); const map = new Map({ layers: [rasterLayer, vectorLayer], target: document.getElementById('map'), view: new View({ center: fromLonLat([126.979293, 37.528787]), zoom: 15, }), });