Oborn, JeremyFlynn, SeanEgbert, ParrisHolladay, SethDiamanti, Olga and Vaxman, Amir2018-04-142018-04-1420181017-4656https://doi.org/10.2312/egs.20181030https://diglib.eg.org:443/handle/10.2312/egs20181030Physics-based fluid simulation often produces unpredictable behavior that is difficult for artists to control. We present a new method for art directing smoke animation using time-reversed simulation. Given a final fluid configuration, our method steps backward in time generating a sequence that, when played forward, is visually similar to traditional forward simulations. This allows artists to create simulations with fast turnaround times that match an exact art-directed shape at any timestep of the simulation. We address a number of challenges associated with time-reversal including the problem of decreasing entropy.Computing methodologiesPhysical simulationSimulation by animationApplied computingMedia arts10.2312/egs.201810301-4