Magic Wand (selection tool by color differences) for Openlayers library
npm install ol-magic-wand
shell
npm install ol-magic-wand
`
Usage
`js
import "ol/ol.css";
import { Map, View } from "ol";
import { Tile as TileLayer } from "ol/layer";
import { OSM } from "ol/source";
import { defaults as defaultInteractions } from "ol/interaction";
import MagicWand from "ol-magic-wand";
let osm = new TileLayer({
source: new OSM()
});
let wand = new MagicWand({
layers: osm
});
const map = new Map({
target: "map",
interactions: defaultInteractions().extend([wand]),
layers: [osm],
view: new View({
center: [0, 0],
zoom: 1
})
});
// set map layer or layers to create snapshot and to draw a mask
wand.setLayers([/ some other layers /]);
// get sequential arrays of points (contours) by the binary mask
let contours = wand.getContours();
// get a data of the current mask: 1-D binary array and top-left corner
let mask = wand.getMask();
// clear the current mask and remove it from the map view
wand.clearMask();
``