> like implicit euler or leapfrog Leapfrog is so easy to implement, as well. It might require a smaller timestep than some fancy techniques but it is very chea

> like implicit euler or leapfrog Leapfrog is so easy to implement, as well. It might require a smaller timestep than some fancy techniques but it is very cheap per timestep. And given that it is accurate enough for statistical Physics simulations, so about 2 orders of magnitude more accurate than it needs to be for a game.