https://github.com/kripken/box2d.js/ Demo: http://kripken.github.io/box2d.js/webgl_demo/box2d.html 演示: http://kripken.github.io/box2d.js/webgl_demo/box2d.html Example code to give you an idea of the API: https://github.com/kripken/box2d.js/blob/maste…