That's just to keep a reference to the sprite along with the body. There's no real magic to it. Later in the 'update' function it loops over each body and updat

That's just to keep a reference to the sprite along with the body. There's no real magic to it. Later in the 'update' function it loops over each body and updates the attached sprite: https://github.com/ryanwilliams/cocos2d-demo-box2d/blob/master/src/main.js#L62 https://github.com/ryanwilliams/cocos2d-demo-box2d/blob/mast...