## Planck.js<sup>&alpha;</sup>

Planck.js (or simply Planck–quantum of action in physics) is a JavaScript rewrite of Box2D C++ game physics library. Planck has a JavaScrip-friendly API and small footprint suitable for web and mobile HTML5 game development.

[![Car](/doc/img/screenshot.png "Play")](http://piqnt.com/planck.js/example/#Car)

Planck includes Box2D algorithms without modification and its internal architecture and external API are close to Box2D. However some [changes](./CHANGES.md) and refactoring are made during rewrite to address differences between C++ and JavaScript.

*Box2D is a popular C++ 2D physics library created by Erin Catto, it is used in several popular games such as Angry Birds, Limbo and Crayon Physics as well as several game development tools and libraries.*

### Development

Install development dependencies:

    npm install
    bower install

Run unit tests:

    npm test

Try examples with live build (see command-line output for URL to open):

    npm run dev