Ol Cesium

OpenLayers - Cesium integration library. Create your map using OpenLayers, and visualize it on a globe with Cesium. See live examples.

ES6 modules

Since version 2.0, the code is entirely based on ES6 modules and syntax. It requires OpenLayers 6.x. A convenient ES6 package olcs is available on npm.

Features

Switch smoothly between 2D and 3D and synchronize:

• Map context (bounding box and zoom level);
• Raster data sources;
• Vector data sources in 2D and 3D;
• Map selection (selected items);
• Animated transitions between map and globe view.

The library is configurable and extensible and allows:

• Lazy or eager loading of Cesium
• Limiting Cesium resource consumption (idle detection)

For synchronization of maps in projections other than EPSG:4326 and EPSG:3857 you need 2 datasets, see the customProj example.

Integration in your application

There are several ways to integrate OL-Cesium in your application. In all cases OpenLayers and Cesium are peer-dependencies of OL-Cesium, your application need to depend on a compatible version of OpenLayers and of Cesium. Note that Cesium is accessed through the global window.Cesium object. OpenLayers is accessed through ES6 imports.

As an ES6 library (recommended method)

npm i --save olcs

Then import the parts you need. Example:

import OLCesium from 'olcs/OLCesium.js';
const ol3d = new OLCesium({map: ol2dMap}); // ol2dMap is the ol.Map instance
ol3d.setEnabled(true);

In addition, you need to expose the Cesium library as window.Cesium. For this, simply add the Cesium script to your html:

<script type="text/javascript" src="..your_path../Cesium.js"></script>

For Cesium integration with Webpack, see ol-cesium-webpack-example.

As an old-fashioned independent library (need update)

• build the library in dist/olcs.js:

npm i --save olcs
npm run build-library

• get the CSS and JS from the full build at https://openlayers.org/download/

• use as follow:

const ol3d = new olcs.OLCesium({map: ol2dMap}); // ol2dMap is the ol.Map instance
ol3d.setEnabled(true);

For the remaining steps, see the old fashioned example. Notably, you need the Cesium library.

As an UMD library (Angular, ...)

npm i --save ol-cesium

The UMD-specific build is located here: node_modules/ol-cesium/dist/olcesium.umd.js

Then import the parts you need. Example:

import OLCesium from 'ol-cesium';
const ol3d = new OLCesium({map: ol2dMap}); // ol2dMap is the ol.Map instance
ol3d.setEnabled(true);

In addition, you need to expose the Cesium library as window.Cesium. For this, simply add the Cesium script to your html:

<script type="text/javascript" src="..your_path../Cesium.js"></script>

Going further

See the examples.

Use properties to control specific aspects of OL-Cesium integration, see the PROPERTIES.MD.

If you are new to Cesium, you should also check the Cesium tutorials.

Running the examples in debug mode

This is useful for contributing to Ol-Cesium, because it loads the source files instead of a minified build:

$ make serve

will make the distribution examples available at http://localhost:3000/examples

Running the unminified version of Cesium

Passing the parameter ?mode=dev to an example will load the debug version of Cesium instead of the minified one. This is helpful when something breaks inside Cesium. In distribution mode, an unminified version of OpenLayers and Ol-Cesium is also loaded.

Limitations

• OpenLayers unmanaged layers are not discoverable and as a consequence not supported. Plain layers should be used instead of the synchronization managed manually. See https://github.com/openlayers/ol-cesium/issues/350.

• OpenLayers interactions are not supported in 3d. See https://github.com/openlayers/ol-cesium/issues/655.

Release process

See RELEASE.md.