Example of a map with a semi-transparent layer.
This example will display a tiled MaxBox layer semi-transparently over an OSM background. The OSM layer is changed to black and white by using a CSS filter.
import 'ol/ol.css';
import Map from 'ol/Map';
import OSM from 'ol/source/OSM';
import TileJSON from 'ol/source/TileJSON';
import TileLayer from 'ol/layer/Tile';
import View from 'ol/View';
import {fromLonLat} from 'ol/proj';
var key =
'Your Mapbox access token from https://mapbox.com/ here';
var map = new Map({
layers: [
new TileLayer({
className: 'bw',
source: new OSM(),
}),
new TileLayer({
source: new TileJSON({
url:
'https://api.tiles.mapbox.com/v4/mapbox.va-quake-aug.json?secure&access_token=' +
key,
crossOrigin: 'anonymous',
// this layer has transparency, so do not fade tiles:
transition: 0,
}),
}) ],
target: 'map',
view: new View({
center: fromLonLat([-77.93255, 37.9555]),
zoom: 7,
}),
});
<!DOCTYPE html>
<html lang="en">
<head>
<title>Semi-Transparent Layer</title>
<!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
<script src="https://unpkg.com/elm-pep"></script>
<style>
.map {
width: 100%;
height:400px;
}
.bw {
filter: grayscale(100%);
}
</style>
</head>
<body>
<div id="map" class="map"></div>
<script src="main.js"></script>
</body>
</html>
{
"name": "semi-transparent-layer",
"dependencies": {
"ol": "6.4.3"
},
"devDependencies": {
"parcel": "1.11.0"
},
"scripts": {
"start": "parcel index.html",
"build": "parcel build --experimental-scope-hoisting --public-url . index.html"
}
}