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A Geo-toolkit built in Javascript.


Terraformer is a modular toolkit for working with geographic data.

The Terraformer project to broken up into a series of smaller modules.

  • Terraformer Core - Contains methods and objects for working with GeoJSON. This also contains common methods used by other modules.
  • WKT Parser - Parse Well Known Text into GeoJSON and vica-versa.
  • ArcGIS Geometry Parser - Parse the ArcGIS Geometry Format into GeoJSON and vica-versa.
  • GeoStore - A framework for persisting and querying GeoJSON features with pluggable indexes and persistant stores.
  • Designed to work in Node and the browser
  • No dependancies of other tools or libraries

Check out the getting started guide which will give you an overview of core concepts and methods in Terraformer.

Make sure your check out the full documentation on the Terraformer website and the getting started guide.

var polygon = new Terraformer.Primitive({
  "type": "Polygon",
  "coordinates": [
      [-122.66589403152467, 45.52290150862236],
      [-122.66926288604736, 45.52291654238294],
      [-122.67115116119385, 45.518406234030586],
      [-122.67325401306151, 45.514000817199715],
      [-122.6684260368347, 45.5127377671934],
      [-122.66765356063841, 45.51694782364431],
      [-122.66589403152467, 45.52290150862236 ]
var point = new Terraformer.Primitive({
  "type": "Point",
  "coordinates": [-122.66947746276854, 45.51775972687403]

Now that you have a point and a polygon primitive you can use the primitive helper methods.

// add a new vertex to our polygon 
polygon.insertVertex([-122.6708507537842, 45.513188859735436], 2);
// figure out if our point is within our polygon 
point.within(polygon); // returns true 

You can also have Terraformer perform many geometric operations like convex hulls and bounding boxes.

var convexHull = polygon.convexHull();
point.within(convexHull); // returns true 
var boundingBox = polygon.bbox(); // returns the geojson bounding box for this object. 

To build the site locally, first bundle install then bundle exec middleman to run a local server. Once you're satisfied, run bundle exec middleman build, then grunt gh-pages to deploy to github pages.

Find a bug or want to request a new feature? Please let us know by submitting an issue.

Esri welcomes contributions from anyone and everyone. Please see our guidelines for contributing.

[](Esri Tags: Terraformer GeoJSON) [](Esri Language: JavaScript)