Tangram is a library for dynamic client-side map rendering with WebGL (with a less-maintained Canvas option), using GeoJSON or binary vector tiles.

Instead of using traditional image tiles, we render from vector tiles that contain the underlying source geometry for each tile's bounding box.

Mapzen provides a free vector tile service that can be used with Tangram for OpenStreetMap base layer data, with worldwide coverage updated daily. There is also an OSM.US-hosted alternative.

Tangram currently supports GeoJSON tiles as well as Mapbox's binary format, both of which can be generated by the Mapzen vector tile service.

Here's an example GeoJSON tile.

The library also includes a Leaflet plugin, Tangram.LeafletLayer, to provide basic web map pan/zoom functionality.

npm install
make

The library will be minified in dist/, and index.html provides an example for rendering from different sources and simple Leaflet integration.

• NYC / Lower Manhattan
• NYC / Central Park
• Berlin
• Colosseum & Roman ruins