Software based on physical models helps artists create realistically animated graphics, but getting an on-screen object to wind up in a particular place is a tedious trial-and-error process. Enter Jovan Popovic of MIT’s Laboratory for Computer Science. He has developed software that gives animators interactive, real-time control over animated graphics. To make a pair of scissors bounce off the floor and land on a coatrack, say, the animator simply clicks on the scissors and drags them first to the floor and then to the rack, determining the scissors’ path on the screen. The computer calculates the starting conditions needed to make the journey happen and does the math that generates realistic animation. Popovic, who did the research while he was a student at Carnegie Mellon University, says his tool will make movie and video game sequences-such as rolling dice, bouncing balls, and colliding objects-more believable. He has begun negotiations to license the software.