Is it possible to fast forward simulation in Box2D

问题

I create a box2d world, put some objects on the screen with different properties like rotation, restitution ,density. And then I start the application. Is it possible to fast forward the simulation so that I can see the result quickly? By result I mean the final state of the world objects. Just like a video clip.

回答1:

Thanks to Andrew I found that if I run the Step function multiple times, I can get the fast forwarded simulation. Here's just a little code that I guess anybody could write:

-(void)simulateWithFastForwardRate:(int)ffRate timeStep:(float32)timeStep
                    velocity:(int)velIters 
       andPositionIterations:(int)posIters{
     for(int i=0;i<ffRate;i++){
       _world->Step(timeStep,velIters,posIters);
     }
}

Just run the above method passing it the fast forward rate, velocity and position iterations.

来源：https://stackoverflow.com/questions/15208549/is-it-possible-to-fast-forward-simulation-in-box2d