The splendid hand-crafted animation for which Disney Studio is noted, has almost taken a back seat to the computer-generated images of Tron. The computer won out over animation, because of its almost unlimited capabilities — namely, the camera isn't bound by any physical limitations. It's no problem to have the computer move the camera three feet from the ground to 50- feet — and have the background change in correct perspective. Camera moves are very difficult with hand animation since one background cannot be used for the entire scene. A series of backgrounds must be drawn for each frame of movement and that, needless to say, can get very costly.
"We had played all the videogames," says Tron's writer-director Steven Lisberger. "And when we investigated computer art, we realized that by combining the concepts of electronic games and computer imaging we could bring something to life that hadn't been there before."
Tron is the first feature to use computer imaging extensively. While other motion pictures such as Westworld, Star Wars, and Demon Seed have used computers as an effect in an environment, Tron uses them to totally create the environment.
Richard Taylor supervised the 20 minutes of computer-generated footage. His firm, Information International, Inc. (Triple-I) of Culver City, Ca., along with Mathemetical Applications Group, Inc. (MAGI) of New York have employed digital computers to create the mind-blasting videogame segments. A computer hook-up between MAGI and Disney avoided any shipping time delays that would otherwise have been necessary for previewing and correcting certain scenes.
Very briefly, here's how designers developed the computer-generated world of Tron. An artist's rendering of a sequence such as the light cycle chase was plotted on a sheet of graph paper. Three views of the shot, the top, side, and bottom, were fed into a digital computer. The computer then knew the precise threedimensional measurements of everything in the shot (In this case, it was the two cycles, their walls of light, the grid pattern on the floor, and the distant graphics on the wall). It thus became possible to choreograph the two cycles' frame-by-frame movements in the scene to perfection.
Next, each object in the sequence had to be assigned a certain color and texture. An older method utilizing analog computers could vary the strength and frequency of electrical waves to create a picture, but the newer digital method employs pulses of electricity to illuminate tiny pixels on a special computer screen. Each pixel was given a certain color hue and intensity. "It's no different from the way they light the big billboards on Times Square," says Larry Elin, head of the MAGI team, "except that the billboard has maybe 8,000 lights and one of our monitors can have over two million pixels."
Despite its seemingly endless capabilities, the computer does have certain drawbacks. There's still an ever-present "video look" that will probably never replace the resolution or subtle color shading of an original frame of celluloid. No doubt we've only seen the tip of the iceberg of what can be achieved with computer graphics. To create the police recognizers, the electronic tanks, or the massive flying aircraft carrier in Tron, it was by far the only way to fly.
