Issue: Volume: 23 Issue: 11 (November 2000)

Refining the Rugrats

Animators use 3D technology to add character to the Rugrats' film adventure

By Karen Moltenbrey

Paris is known for its sophisticated culture, but can the atmosphere alone turn the Rugrats, Nickelodeon's famous group of rowdy, runny-nosed children, into well-mannered little ladies and lads? Impossible. Instead, the baby bunch from morning cable television only seems to increase the wattage of the City of Lights during the group's second animated film feature, Rugrats in Paris-The Movie, scheduled to be shown in theaters beginning mid-November.

In their new adventure, the precocious animated characters-who act their age only in the presence of adults-travel to Paris for a vacation. Stu Pickles, father of one-year-old Tommy, is summoned to Paris's new amusement park, EuroReptarland, to repair his Reptar invention-a 50-foot T-Rex robot that is the park's main attraction. Also along for the fun (and romance) are Tommy's best friend, Chuckie, who is searching for a new mom, and Chuckie's dad, Chazz, who is looking for love. They are accompanied by the rest of the half-pints: twins Phil and Lil, baby Dil, and bratty Angelica. When the parents become preoccupied, the children set their sights on the various city sites, and chaos ensues.

In keeping with the classic Rugrats style of creators Arlene Klasky, Gabor Csupo, and Paul Germain, the artists at Hollywood's Klasky Csupo Studios used traditional 2D cel animation to create the majority of the film's cast and the backgrounds. In some instances, however, the complexity of the scenes required a smattering of 3D objects and backgrounds. The majority of the 3D CGI, though, centered on two main characters from the park-Reptar and Robo-snail. "We wanted to have the strength and agility of 3D along with the textures of 2D, but we needed the elements to look like they belonged in the same world," says Jerry Mills, director of digital technology at Klasky Csupo.
Although the new Rugrats in Paris is animated in a traditional style, the film contains numerous 3D scenes and models. The animators at Hollywood-based Klasky Csupo used Alias|Wavefront's Maya to build the 3D models, then used Animo Inkworks' renderer and

For the 2D images, a team of animators created more than 300,000 drawings by hand, which were scanned into Toon Boom Technologies' (Montreal) US Animation software for inking and painting. The package was also used for the majority of the compositing and data-management tasks. The backgrounds were also hand-drawn, then scanned and placed into Adobe Systems' (San Jose, CA) Photoshop running on Macintoshes, where they were digitally painted.

To create all the 3D models, the group used Alias|Wavefront's (Toronto) Maya. To seamlessly blend the 3D images into the 2D environments, Klasky Csupo passed the majority of the CGI through Cambridge Animation Systems' (Cambridge, UK) Animo Inkworks renderer. This created a hidden-line rendering that was fed back into Toon Boom, where it was vectorized and painted-similar to how the 2D images were processed. This gave the 3D images a hand-drawn cartoon effect.

"In a few instances, we used Maya's renderer to add color to the 3D images," Mills notes. "But for the most part, we used Inkworks to toon-shade lines on the 3D models and to create objects for the 2D animators to reference."

In fact, Mills says the group used Toon Boom as its primary platform and all the other packages as plug-ins. "Using one main package allowed us to maintain and control our art direction, which resulted in eye-pleasing compatibility of the 2D and 3D elements."

Since the 3D images were processed in the same way as the 2D elements, why didn't Klasky Csupo use traditional cel animation for the entire project, as it does for the Rugrats television show? According to Mills, an audience's expectations are far greater for a film than for television, and 3D enabled the artists to achieve the desired effects and higher level of detail required in certain scenes. "2D would have been a very poor substitute, and it would have destroyed the movie in some instances," he says. "We didn't use 3D just because it made things easier; it gave us the best finished product."

Reptar, one of the main characters, required a tremendous amount of motion, so the artists created a fully articulated model, from its hips to its jaw. "As part of the movie's plot, the kids take control of Reptar to get from point A to point B. But it's not a realistic, fluid type of motion; it's what you'd expect from a toddler in a virtual reality suit, driving a 50-foot robot," says Mills. "Reptar is not supposed to move like Godzilla; it's supposed to move like Godzilla if it were being controlled by a kid."

Although a giant 3D rolling Reptar wagon debuted in the first Rugrats film a few years ago, the model was completely remodeled for its Paris appearance so that it would possess the requisite controls, access hatches, and other robotic parts. "The redesign of that one model was extremely time-consuming," Mills notes. "And once we got the design down, we had to look at how it animated. Did it move the way we wanted? It often looked good as a static model, but it didn't allow us to move it as we intended, so we had to literally go back to the drawing board."
In a departure from the traditionally animated Rugrats television series, the film introduces two new characters, Reptar (shown here) and Robo-snail, which were created using 3D computer graphics. To seamlessly blend the 3D models into the 2D movie scenes

To make Reptar walk as if controlled by a child required the minds and strides of dozens of animators. At one point, the director, Stig Bergqvist, donned a dinosaur suit and tried to achieve the desired gate. "We did whatever it took to communicate our ideas and expectations, which were unlike anything we'd seen in reference footage," explains Mills. After numerous attempts by various artists, Bill Wright, a 3D lead animator, finally got Reptar into his groove. Once that was accomplished, the animators had to ensure that the movement between the 3D and 2D characters was fluid and blended seamlessly.

Although Rugrats in Paris is considered a traditionally animated film, more than one-quarter of the scenes contain some type of 3D animation. "I think most people will be able to pick out some of the major 3D elements, but there are a lot of models in the film that people won't catch as being 3D," Mills says. "It was a conscious decision to tone down the 3D effects. We didn't want those items popping off the screen."

Animo Inkworks, Cambridge Animation Systems (