[degenerate]

In most of the demos, you can grab the objects and drag them around. In other demos (like 8 ball) you can 'shoot' them.

I wasn't expecting it to be so smooth and precise... this is really great work. It makes me realize why I got a C in physics, because I could never make this!

[efnx]

It's not just physics though, as I remember Erin the author of box2d mentioning that most of the work is concerned with allocating and deallocating tiny pieces of memory. After that the physics are rather simple Newtonian equations.

[outworlder]

But then, in order to calculate those newtonian equations, you need an integrator, right?