Monday's course, "Artificial Life for Graphics, Animation, Multimedia, and Virtual Reality," Thursday's panel on "Behavioral Modeling and Animation: Past, Present and Future."

Boids by Craig Reynolds










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Playing God with Artificial Life


If you've seen Tim Burton's 1992 movie, "Batman Returns," you've had a glimpse of behavioral animation, the most far-reaching extension of the notion of synthetic actors theme. Those swarming, lifelike bats that took you by surprise weren't individually drawn or controlled; they were constructed by a computer program that created each bat, gave it a few simple rules about how to fly relative to the others, and then let them all loose.

Barely a decade old, behavioral animation moves beyond both cartoonish characters and real humans to imagine other possible forms of life. It is based on the nascent science called artificial life, which formally models living processes like growth, ecological adaptation, biomechanics, and evolution to imagine forms of life which do not exist on Earth. Behavioral animation gives these artificial life creatures the only life they will ever experience on our planet, life on a screen.

The bats were based on the work of Craig Reynolds, now a software developer at DreamWorks SKG. In 1986 he wrote a program called "Boids," which simulates different flocking behaviors. Tweak the numbers and a cloud of randomly dancing mosquitoes turns into a schooling shoal of fish. It has become a landmark in behavioral animation and artificial life research.

Reynolds is still putting familiar-looking artificial life characters on the big screen. "I make models to which are attached animated characters to create crowd scenes and various kinds of background action," he explains. His technique has been used on several other films, including the wildebeest stampede in Disney's "Lion King," the upcoming "Prince of Egypt" and another DreamWorks project so secret, "I could tell you about it, but then I'd have to kill you."

Given the dangers posed by even artificial life forms in Hollywood, maybe I'll just send my avatar to the next interview.


Modeling | Rendering | Animation | Interaction | Virtual Reality | Synthetic Actors