README.md

openlayers-side-by-side

A Openlayers control to add a split screen to compare two map overlays.

Creates a new Openlayers Control for comparing two layers or collections of layers.

Methods

Method	Returns	Description
setLeftLayer	this	Set the layer(s) for the left side
setRightLayer	this	Set the layer(s) for the right side
remove	void	Close split screen
open	void	Open(Reopen) split screen

Usage

Add the script to the top of your page :

<script src="ol-side-by-side.min.js"></script>
<link rel="stylesheet" href="ol-side-by-side.min.css"></link>

Or if you are using browserify:

import SDSControl from 'ol-side-by-side';

Then create a map, add two layers to it, and create the SideBySide control and add it to the map:

import Map from 'ol/Map';
import TileLayer from 'ol/layer/Tile'
import OSM from 'ol/source/OSM';
import XYZ from 'ol/source/XYZ'
import View from 'ol/View';

import 'ol/src/ol.css';

let layer1 = new TileLayer({
    source: new OSM()
});
let key = 'your key from https://www.maptiler.com';
var attributions = '<a href="https://www.maptiler.com/copyright/" target="_blank">&copy; MapTiler</a> ' +
  '<a href="https://www.openstreetmap.org/copyright" target="_blank">&copy; OpenStreetMap contributors</a>';

let layer2 = new TileLayer({
    source: new XYZ({
      attributions: attributions,
      url: 'https://api.maptiler.com/tiles/satellite/{z}/{x}/{y}.jpg?key=' + key,
      maxZoom: 20
    })
});
let sds = new SDSControl();

let map = new Map({
    layers: [layer1, layer2],
    target: 'map',
    view: new View({
        center: [0, 0],
        zoom: 0,
    }),
    controls:[
        sds,
    ]
});

sds.open()
sds.setLeftLayer(layer2);
sds.setRightLayer(layer1);

Limitations

• The divider is not movable with IE.
• Probably won't work in IE8, but what does?

License

Apache2