Computer Graphics World

November 2008 22 n n n n CG Animation believes in his hero and encourages Bolt to display his superskills. When Bolt warns Rhino that their journey could be danger ous, the little hamster replies from inside his glass bowl, "I eat danger for breakfast." "Rhino is like the kid who would throw a towel around his neck like Superman and jump off a roof," says Nathan Greno, super vising storyboard director, who joined the crew as Lasseter and Ed Catmull took the reins at Disney Animation. Although Bolt was always a dog and Mittens always a cat, originally Rhino was a rat. "Everything was up for grabs," Greno says. Rhino turned into a hamster during a retreat. "We were with about 35 or 40 directors from Pixar and Disney, and someone said, 'I always wanted to do a hamster in a ball,' " Clark says. "We all knew, at that moment, we'd have a hamster in a ball." Animal Truth Disney casts animators based on their skills, and organizes the supervisors by character. Sixtytwo animators worked on Bolt, led by six supervisors. Clay Kaytis led the team of animators working on Rhino. "Of all the characters, Rhino has the most controls," Kaytis says. "He's the most complicated because he is fat and round, and volumes want to crash." e anima tors worked in Autodesk's Maya using rigs that allow for squash and stretch. Deform ers rode on the topology to simulate what a muscle system would do, but calculated the blendshapes only on surface changes. Kaytis moved Rhino's belly with a control button; the hamster's whiskers, though, moved automatically. All the animals talk, except when hu mans are on screen, and the animators started working on shots by listening to the dialog. "I started with the character in a set, in a layout pose," says Kaytis. "en I lis tened to the audio over and over, to under stand what the throat is doing and when to take a breath. I did five frames of poses to show the director. And then I shut the door and worked for a couple days." Rhino is the most anthropomorphic of all the animals because he stands up inside his bubble; otherwise, all the fourlegged animals stay on all fours. "John [Lasseter] has certain rules," Kaytis says. "Well, maybe not rules, but consistencies. His mantra is truth in materials; something has to move the way it looks. So, if an animal looks like a dog, it should move like a dog." Although Bolt looks cartoony in his TV show, when he's outside, he's in the real world, which meant he needed to move realistically. To help the animators under stand realworld animal behavior for the dog, cat, hamster, and other critters in the film, Disney had trainers bring various animals into the studio and had Dr. Stuart Sumida, a biology and anatomy professor at California State University in San Ber nardino, teach classes. In addition, Rhino animators could observe a real hamster named Doink, which joined the crew and had his own glass ball. Sometimes, though, the filmmakers needed to fudge accuracy. For example: "We reached a point when we thought we had nailed the dog," Kaytis says. "We had animated a couple sequences. But he wasn't appealing. So, we looked at the dogs in Lady and the Tramp, at the shape of their brows, how their muzzles worked, their ears, and their eyestoface relationship. And then we remodeled Bolt's face." ey gave him a larger brow ridge, made his eyes bigger and rounder, and changed the fur color on parts of his face. Dogged Artists Art director Paul Felix—who came to Bolt with credits as a production designer for Lilo & Stitch and e Emperor's New Groove, visual development artist for Brother Bear and Mulan, location designer for Tarzan, and character designer for Mulan—also considered Lady and the Tramp when he began working on the film. e journey that Bolt, Mittens, and Rhi no take from New York City to Hollywood sends them trotting (and rolling) across the US, which meant the crew needed to design and build what Adolph Lusinsky, the film's look and lighting director, calls "200 envi ronments on a 30environment budget." To design the environments, Felix refer enced early Disney films and the Ashcan School of art. "I liked the sense of place in Disney films like Mickey and the Beanstalk, Peter Pan, and Pinocchio, and the dirty quality and looseness in American painter Edward Hopper's architectural settings," Felix says. Hopper's watercolors and paint ings often include Impressionist back ground buildings and simplified geometry, which, while accurate in detail, is none theless abstract. "I like the idea of simple Rhino, the hamster in the ball, tells his hero Bolt that he'd be a big help. Mittens, the cat leashed to Bolt, isn't convinced. About 400 artists, including 62 animators, worked for 88 weeks on the film.

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