Water has always been a challenge for CG animators. So “Finding Nemo” was tough. Thirteen years later, Pixar has made great strides for “Finding Dory,” thanks to advancements in rendering, lighting and animation.
“There’s an aesthetic that the first film brought that we’re continuing to follow,” said supervising Technical Director John Halstead. “One thing that’s changed, though, is we start from a place that’s much more grounded in reality. And then we have a choice of what we want to highlight or push back and de-emphasize.”
This time around, according to supervising animator Mike Stocker, Pixar had to relearn how different species of fish swim and carve through the water. And then they added another layer of acting on top.
“Dory [Ellen De Generis] as the main character was the tricky part,” Stocker said, “in dealing with her short-term memory loss. How does she process information? When does she forget? When does she remember?”
By contrast, Hank, the cantankerous octopus (Ed O’Neill), presents the perfect foil to Dory’s sweet sincerity in this buddy comedy.
“How do you create an octopus, which looks like anarchy of motion,” asked Jeremie Talbot, the character supervisor,” and then distill that into something that looks designed and elegant and fits in that Dory world?”
“There are so many parts that we had to break him apart,” Talbot continued. “How do the suckers work? Simulation took on that task. What about the webbing between the legs and how that interacts with the face? The character department tackled that. And the art department figured out the overall aesthetic of Hank and how that fit in with the limitations of technology.”
However, it never occurred to anyone at Pixar that Hank’s camouflaging ability made him similar to the villainous Randall from “Monsters, Inc.”
“We were too busy researching the octopus and never made that connection,” Talbot said. “Characters are like action figures that get handed over to animation and you never know what they’re going to do with them.”
The biggest tech leap on “Finding Dory” (under the direction of CTO Steve May) was the addition of Renderman RIS to the Pixar pipeline: a new and more efficient rendering paradigm for global illumination, specifically for ray-tracing heavy geometry, hair and bright and shiny surfaces. This allowed for reflection and refraction in water to look more naturalistic.
“You can see that a lot when we’re in the Marine Life Institute [modeled after the Monterey Bay Aquarium],” said Halstead. “That environment has so much glass and water, and now we’re able to describe that.”
Pixar also integrated Katana (The Foundry’s collaborative lighting and look development tool) into Renderman, which allows live rendering opportunities for the animator.
In addition, tweaks were made to Pixar’s proprietary Presto animation software for creating automatic swim movements for the fish. And Pixar adopted Universal Scene Description (USD), a coordination tool for creating and sampling graphics applications among various departments, which Pixar will offer this year as an open source tool to the industry.
Halstead praised Sketch to Pose, which was added to Presto. “You can sketch out curves and have rigs follow those curves,” he said, “which allowed animation to speed up blocking.”
Dory, of course, had to be in water at all times, which provided some interesting and funny framing choices, as when, for example, Hank carries the blue fish around in a coffee pot as they carry on conversations.
“After a while, you forget how bizarre these situations are and they become second nature,” said Jeremy Lasky, the DP in charge of camera, who experimented with 16mm virtual cinematography for underwater scenes.
After all, on “Finding Dory,” achieving greater naturalism was the whole idea.