Reeling in a whopper: DreamWorks' first all-Glendale CG film uses custom plug-ins to great effect

Post, Oct, 2004 by Ken McGorry

GLENDALE, CA -- DreamWorks' new CG comedy Shark Tale has to compete with successes like Pixar's Finding Nemo not only with winning storytelling, but also by pushing the envelope with a gorgeous overall look. The Shark Tale team, based solely here in Glendale, also had to create custom lighting and effects for their undersea fantasy world while a Glendale sister group worked on Shrek 2 in tandem with DreamWorks PDI upstate. Both aimed to push CG global illumination forward.

While Shark Tale and Shrek 2 were being produced in parallel, visual effects supervisor Doug Cooper says, Shark Tale was destined to be among the last DreamWorks films to use Alias Maya for animation and Pixar RenderMan and Mental Ray renderfarms. DreamWorks is on the verge of shifting to a proprietary workflow and pipeline for all future movies. The company has adopted an all-HP Linux pipeline for CG production and rendering, and will produce its future films with proprietary software such as "Emo," an animation tool set developed with PDI, and "Light," a special lighting package. The DreamWorks/Aaardman film Flushed Away, set for 2006 (the first Aardman film to make the switch from stop motion to CG), is the last film slated to use Maya for animation, although Maya will still serve for modeling and effects.

The Shark Tale pipeline employed over 300 HP dual-processor workstations for everything from animation to rendering. HP technology enabled the animators, designers and everybody working on the film to see greater detail from their own desktops as scenes progressed.

LIGHTING MEANS SO MUCH

For Shark Tale, Cooper and his team had to create and light stunning underwater environs that pair fantasy with natural beauty by plugging in "special sauce" lighting effects, developed by his Glendale team, into the numerous Mental Ray and RenderMan renderers. The visual effects team also brought on and trained additional lighting people, numbering close to 70 as the show's deadline loomed.

Cooper says production designer Dan St. Pierre called for an undersea environment that was "so fantastic yet so believable I'd want to go there." One technique is "colored light," filtered rays that strike characters and objects in an impressionistic yet still realistic way.

Another, "ambient occlusion," Cooper says is an original ILM term for exposure mapping in which "areas with crevices or which are obscured naturally go dark and in shadow, while exposed areas are lighter." Bounce lighting and subsurface scattering are global-illumination techniques used in Shrek 2. Bounce lighting allows an artist to easily reflect light in spots where it's naturally found, like under a chin, and subsurface scattering gives skin--or in this case, scales--a warmer, more natural glow. Cooper credits the decision to go with AMD's new Athlon chips in the HP computers as a saving grace in the "massive amount of lighting rendering" that was necessary. He says that the Glendale facility's custom lighting plug-ins allowed for "realistic lighting that's very direct-able and stylized, not push-button. As we move forward," Cooper says, "we're now taking the key technologies from Shark Tale and incorporating it into our proprietary pipeline for future films."

CITY BENEATH THE SEA

Lead CG supervisor Kevin Rafferty wanted "incredible depth and detail" in Shark Tale's undersea city, Cooper says. "Each window is a unique shape" in the coral buildings, and this detail called for more massive computing power to blend the amorphous shape of natural coral with the repetitive structure of city buildings. There are also funkier neighborhoods with distinctive brownstone dwellings with stoops.

Even decorative props like kelp and sea grass undulate realistically in the backgrounds. Particulate matter, the detritus that floats through any natural underwater environment, also got special attention--just the right amount was used to subtly remind viewers they were submerged.

An effect Cooper gets a kick out of is the bubble trails that follow characters' movements throughout the film. The rule of thumb there is that the bubbles subtly trail off behind fish departing a scene, following the line of action to impart a sense of speed and motion.

WORKIN' IN THE WHALE WASH

The film's "Car Wash" sequence, featuring a remake of the hit song, is a prime showstopping example of character animation, effects and music coming together on a grand scale. Cooper's bubbles play an important role as a giant sperm whale gets a bath at our hero Oscar's place of employment. Here the suds that worker fish scrub into the whale customers behave in a predictable foamy way, and then disperse into the seawater.

Supervising animator Fabio Lignini holds the "Car Wash" scenes as one of his favorites, given the close to 40 animated characters working and performing in the sequence. "We had a choreographer come in," Lignini says," who did the dance routines for all the different stations of the car wash. She did a very thorough job of giving distinct moves to the waxing turtles and the soapers, like Oscar." Groups of dancing fish in this number were given slight variations to their synchronized moves for added realism. This is easy to do in Maya, Lignini says, "providing the rigs are all similar and will accept animation from another rig.