Life of Pi: Grabbing the CG Tiger by the Tail
But the tiger wasn't the only part that Rhythm & Hues worked on. There were virtual water and skies, flying fish, Meerkat Island and bioluminescence. Yet the water and skies were integral. Indeed, Westenhofer says they spent nearly as much time creating the water tools as building the tiger.
"Everything on the ocean was shot on a stage," he explains. "We had a custom water tank built by Aquatics Design Group (ADG) so we could control the waves from shot to shot. They could be powerful and also have a sense of an ocean swell. There was directionality and a programmed motor to vary the strength and speed of each wave. This provided different looks and wave patterns."
But R&H enhanced it with CG water that would vary from shot to shot. The wave artist would time what frame the wave peaked at along with the cadence and they'd plug that into the first order of the wave algorithms. "We would enhance the ocean to get what Ang wanted by increasing the swells or some event in the background," Westenhofer adds. "Then we'd marry the fine details together with little wind ripples. The ability to put wind patterns in with the fluid dynamic system was time consuming."
They used Houdini as the base with their own tools and ended up with 60 different water looks, which ranged from a week to three months to develop. The hardest water was the morning after the storm. Sizable swells with a lot of wind detail on the surface were required. "Getting all the octaves right was a challenge," Westenhofer suggests. "When wind goes through water it causes a ringing effect. We built in mini white caps and foam that would land on the surface. It had to work even in close-up. We spent so much time on the surface of the water for an extended period, and Ang wanted the water to be a character, which was code for the water and the skies set the mood for each sequence.
If you want a gig in visual effects, doing the skies on Life of Pi in Southern Taiwan was the one to get, according to Westenhofer. "We sent someone with our HDRI rig (a Canon 5D with a motorized mouth to circle through eight different positions). It helped to be on the beach because the cloud patterns are often distinctive and dramatic when you're in a marine environment, so we built up a library and took advantage when certain artists went on vacation in places such as Hawaii.
"Halon did the previs with Ang and the finished movie is pretty close. He definitely knows what he wants, but he can be enigmatic with his [instructions]. I'd get a description that he wanted the clouds to be melancholy. It would be up to me to interpret what that meant."
What was Westenhofer's takeaway from Life of Pi? He got to spend eight weeks with a real tiger.
Bill Desowitz is former senior editor of AWN and VFXWorld, the owner of Immersed in Movies (www.billdesowitz.com), a columnist for Thompson on Hollywood at Indiewire and author of James Bond Unmasked (www.jamesbondunmasked.com), which chronicles the 50-year evolution of 007 on screen, featuring interviews with all six actors.