Source: control/union.js

  1. import OL3Parser from 'jsts/org/locationtech/jts/io/OL3Parser';
  2. import { OverlayOp } from 'jsts/org/locationtech/jts/operation/overlay';
  3. import LinearRing from 'ol/geom/LinearRing';
  4. import {
  5.   Point,
  6.   LineString,
  7.   Polygon,
  8.   MultiPoint,
  9.   MultiLineString,
  10.   MultiPolygon,
  11. } from 'ol/geom';
  12. import TopologyControl from './topology';
  13. import unionSVG from '../../img/union.svg';
  15. /**
  16.  * Control for creating a union of geometries.
  17.  * @extends {Control}
  18.  * @alias ole.Union
  19.  */
  20. class Union extends TopologyControl {
  21.   /**
  22.    * @inheritdoc
  23.    * @param {Object} [options] Control options.
  24.    * @param {number} [options.hitTolerance] Select tolerance in pixels
  25.    *   (default is 10)
  26.    */
  27.   constructor(options) {
  28.     super({
  29.       title: 'Union',
  30.       className: 'ole-control-union',
  31.       image: unionSVG,
  32.       ...options,
  33.     });
  34.   }
  36.   /**
  37.    * Apply a union for given features.
  38.    * @param {Array.<ol.Feature>} features Features to union.
  39.    */
  40.   applyTopologyOperation(features) {
  41.     super.applyTopologyOperation(features);
  42.     const parser = new OL3Parser();
  43.     parser.inject(
  44.       Point,
  45.       LineString,
  46.       LinearRing,
  47.       Polygon,
  48.       MultiPoint,
  49.       MultiLineString,
  50.       MultiPolygon,
  51.     );
  53.     for (let i = 1; i < features.length; i += 1) {
  54.       const geom = parser.read(features[0].getGeometry());
  55.       const otherGeom = parser.read(features[i].getGeometry());
  56.       const unionGeom = OverlayOp.union(geom, otherGeom);
  57.       features[0].setGeometry(parser.write(unionGeom));
  58.       features[i].setGeometry(null);
  59.     }
  60.   }
  61. }
  63. export default Union;