AI Zombies Wreak Havoc In World War Z

Tuesday, July 9, 2013

 Special Effects
To achieve the mass crowd effects in the movie World War Z, the film makers turned to a form of artificial intelligence. Visual effects firm Motion Picture Company picked up on an idea that WETA used for the Lord of the Rings movies - to make each zombie an individual actor with goals and behaviors.

For the Brad Pitt film World War Z, London-based VFX house Moving Picture Company had to make enormous zombie hoards behave with a bit of intelligence.

World War Z is an apocalyptic horror film directed by Marc Forster. The screenplay is loosely based on the 2006 novel of the same name by Max Brooks.

World War Z Zombie Horde

Related articles
Animating the sequences by hand would not have allowed the thousands of zombie 'actors' to be in the shots, so the company turned to artificial intelligence.  Using digital creatures, whose movements came from motion-capture performances of real people running up nets and falling down ramps, the team programmed a kind of artificial intelligence, a proprietary crowd-simulation program called Alice.

This type of crowd animation intelligence was pioneered in the Lord of the Rings movies by WETA Digital's Massive software. Through the use of fuzzy logic, the software enables every agent to respond individually to its surroundings, including other agents.

These reactions affect the agent's behavior, changing how they act by controlling pre-recorded animation clips, for example by blending between such clips, to create characters that move, act, and react realistically.

For the movie’s massive piles of Zs in Jerusalem, the VFX company—one of a handful that worked on World War Z—had to build zombie “agents” that could “act” on their own. The
“All complex crowd shots got layers of hand-animated zombies,” said MPC senior CG supervisor Max Wood. “We’d start off setting the shots up in Alice, our in-house crowd tool, then we’d work out where we wanted to add the additional animation detail.”

How long before such crowd software makes it's way into video games and virtual worlds?


By 33rd SquareSubscribe to 33rd Square