A Fish Tale
Issue: Volume 39 Issue 3: (May/Jun 2016)

A Fish Tale

Pixar Animation Studios sends forgetful Dory on a family-seeking journey in their latest CG animated feature

In Disney/Pixar’s 2003 animated feature, the popular Finding Nemo, a forgetful blue tang fish named Dory helped reunite the clownfish Marlin with his son Nemo. Now, upbeat, perky Dory has her own movie titled Finding Dory. 

But wait. Dory has no short-term memory. How would anyone know if she were lost, not the least Dory herself? If she were lost, how could she find her way back? And, would she want to?

“Dory was not wired up to be a main character,” says Finding Dory Director and Writer Andrew Stanton. “Self-reflection is the reason you can follow why a character grows. But, we gave her short-term memory loss. She has emotional memory, but she can’t track progress. So, how do you give her the opportunity of self-reflection when she can’t do it herself? I would never recommend this to a writer.”

Stanton, however, had an advantage over other writers who might try. He wrote and directed Finding Nemo, receiving an Oscar nomination for writing and a Best Animated Feature Oscar for directing the film. In addition, he has received an Oscar for directing Wall-E, and Oscar nominations for writing Toy Story, Wall-E, and Toy Story 3. Thus, he knew the characters in Finding Nemo better than anyone else, and he knows how to move characters from one film into another. But, why did he choose such an unlikely main character?

“I saw Dory as a tragic character,” Stanton says. “I knew her backstory. She used optimism, charm, and selflessness to make sure people wouldn’t ditch her. It was her protection. This story is about Dory finding herself – in every way. I felt she deserved to like who she is.”

Ellen DeGeneres was Stanton’s choice to voice Dory in Finding Nemo, and she returned for this film. 

“Ellen is the only person I ever wrote for specifically,” Stanton says. “Thank goodness she said, ‘yes.’ ”

Also returning is Albert Brooks as Nemo’s father, Marlin. Stepping in to fill Nemo’s fin in Finding Dory is 12-year-old Actor Hayden Rolence.

A crew that topped 400 in all, but averaged 280 on a day-to-day basis, worked on the film. Of those, nearly 100 in the art, story, and editorial departments spent more than two years creating the story, designing the world, and developing the new characters. Storyboarding alone extended over two and a half years, resulting in 103,639 storyboards. Helping Stanton, who is also a vice president at Pixar, was Co-director Angus MacLane. 

The first sequences moved into production approximately a year before the June 17, 2016, release date. Many of the technical challenges for the production crew centered on an octopus’s special needs, on compositing water simulations, and on new tools for working with Pixar RenderMan RIS. 

Help from Her Friends

The story begins in the colorful, cozy coral reef where Dory, Marlin, and Nemo have made a home. It’s a happy family time until a massive stingray migration swims through the neighborhood and triggers deep memories in Dory of a family she thinks she might have left behind. 

“While Dory forgets details in her day-to-day life, her emotional memory is fine,” says Producer Lindsay Collins. 

Determined to uncover her past, Dory talks Marlin and Nemo into helping her find her long-lost family. The search sends the three fish back across the ocean to a Marine Life Institute (MLI), a rescue rehabilitation center and aquarium loosely based on California’s Monterey Bay Aquarium, and into a kelp forest nearby.

At MLI, Dory meets the other three stars of this film: a beluga whale with faulty sonar skills named Bailey, a clumsy nearsighted whale shark named Destiny, and a seven-legged octopus named Hank. 

“I saw a beluga whale in Vancouver and couldn’t keep my eyes off it,” Stanton says. “The animator in me wanted to see what kind of character that species would be.”

Character Designer Jason Deamer created the caricatured whale.

“He’s like a giant pork bun,” Deamer says. “I looked at pork buns for reference, for the texture of his skin. It’s soft, with ripples.”

For Destiny, Deamer picked an even more unusual reference.

“She was weirdly difficult to design,” he says. “I pitched the idea of thinking of her as an oven mitt with big mouth shapes. But we painted her like the real thing.”

Bailey is gray. Destiny has evenly spaced dots on her tail, a more chaotic pattern on her middle section, with increasingly dense dots moving forward to her head.

  As for Hank, he was the most challenging of the three new characters for Deamer, the technical directors, and the animators. But, arguably, the most helpful to Dory. 

“We had to move Dory across the Marine Life Institute,” Stanton says. “So one reason we thought of Hank was because he’s so ambulatory, and octopuses are known for being good escape artists.” In one scene, for example, Hank grabs a ride on a visitor’s back, camouflaged as a backpack. 


“Hank is my favorite character in the movie, and he was one of the hardest things we’ve done on a character level,” Deamer says. “We wanted him to be a lovable, grumpy, old octopus. But what makes an octopus look old? We struggled so hard to make him appealing. These things are slimy and gross. They’re super intelligent, but that sideways eye thing doesn’t make you think of motherly love. And where do we put his mouth? We ended up tucking it under his tentacles.”

For Hank’s color, red was the obvious choice.

“Hank is red because we thought if an animal could change color, he’d choose orangey red,” Deamer says. “And, it contrasts with Dory’s blue.” 

But Hank also changes color. And patterns. And shape. He’s a cat on a wall poster, a camouflage backpack, even a potted plant. To create those textures and colors, the team wanted to mimic how these changes happen in the real world.

“We wanted it to look natural and not like a cross-fade,” says Jeremie Talbot, character supervisor. “Our artists wanted to do something similar in the computer to what happens on a cellular level on animals.” 

Simply put, the artists manipulate many circles, dots if you will, that create a texture with changing colors over Hank’s body. 

“When we combined that with noise, we got a naturalistic effect,” Talbot says. “Hank could match a background or a supplied painting.” Finding a way to make that work took the team two years.

Creating Hank’s shifting shapes fell largely to the animators, but with new tools and sophisticated rigs making it possible. Even so, a shot of Hank sliding into an aquarium, for example, took six months for the animators to do.

“That’s how hard it was to animate this character,” says Mike Stocker, one of two supervising animators on the show. “We had two challenges. Getting all those suckers moving, and getting a rolling feeling for the tentacles. The muscle starts from the body and works to the tip, and that rolling feeling was something we wanted. Jeremy [Talbot] made a super complicated rig. We could use a ‘grab cylinder’ that I called the elbow. We had to lead with the elbow, not the end of the tentacle, to get an octopus feel.”

Another tool within Presto, Pixar’s proprietary animation system, gave the animators a starting point. 

“We could draw a tentacle and snap the model to the drawing,” Stocker says. “That got us 60 percent of the way. Then, we polished the pose.” 

Talbot’s character department created the rig that animators used to pose Hank and his seven tentacles. One of the first reference videos Talbot looked at to determine how an octopus would move was of a mutable creature sliding into a bottle.

“It terrified me,” he says. “Not the look, but how it moved over a rough surface; the way the flesh rolled.”

First, the team created a control that animators could use to set the depth of the webbing between the tentacles, and developed a new curve function. 

“After a lot of work, we had something for animation to play with,” Talbot says. “But, we didn’t have the sliding motion we needed.”

For that, the rigging crew turned to the simulation department for help. There are 350 suckers on Hank’s tentacles, and each sucker needed to squish, stick, and pull away in a believable manner. Solid mechanics came to the rescue.

“There’s a whole branch of engineering that, given a force applied to an object, asks how are all the points in that object moved, displaced, and stressed,” says John Halsted, supervising technical director. “We borrowed approaches from that field of science to figure out how Hank moves.”

Thus, each of Hank’s suckers has a little tetrahedral mesh that provides input into a customized simulator. The simulator produces the squashing and sticking; it deforms the little sucker based on applied forces.

“The simulator is a heavily customized version of Physbam,” Halsted says. “It uses finite-element analysis (FEA) to have a solid, elastic material behave like muscles or flesh. We use the tetrahedral mesh to do the volume-based jiggle and solve it with FEA. To get the skin sliding, we used a triangle mesh over his body.”

Once the team managed to create one sucker that would squish, stick, and pull away, they could propagate the method to all the suckers. Then, they needed to make the tentacles look soft and fleshy as it squished along. 

“A separate skin simulation allowed the skin to move along the same plane as the outer surface of the body,” Halsted says. “It doesn’t break the silhouette. It just slides along.” 

The techniques used to create Hank’s simulation are likely to result in a SIGGRAPH talk this year.


The second challenge for the technical crew centered on water. When Pixar created oceans of water for Finding Nemo 13 years ago, 3D water simulation was in its infancy. For this show, the team concentrated its efforts on water compositing.

“The way we approach effects is that if the characters are in a large body of water, we do a smaller domain where they are playing,” Halsted says, “a play area where they can jump around and break the water apart. So we worked on techniques for this film in which we take a large body of water usually shaped with procedural systems, and composite in the 3D simulation from the play area such that the boundaries are seamless.”

For fluid simulations, the team used Side Effects Software’s Houdini; for lighting, The Foundry’s Katana; for rendering, RenderMan RIS.  

“We came up with a new system for doing the water composite that makes heavy use of an implicit field API to generate the surfaces,” Halsted explains. “We also worked on water shading to make sure the water looked as good as it could. And we made all this work within the new renderer.” 

The fish in Finding Nemo spent most of the film in the ocean. Finding Dory’s setting in the Marine Life Institute meant that often the fish in this film were in the aquarium’s glass tanks. The lighting crew, led by Ian Megibben, put the new renderer through its paces for test shots with Dory in a fish tank and Hank staring in at her from outside.

“There’s an inherent quality to the way water bends, refracts, magnifies, and scatters light,” Megibben says. “Water inside a glass tank is like a fun house. There’s magnification, distortion, and reflections. When the camera is from Dory’s point of view, we see reflections that create a boundary between her and Hank.”

Because Finding Dory is the first film for which Pixar used the RIS architecture, they employed Katana to author new shaders.  

“It was a huge change,” says CTO Steve May. “It affected all the back-end departments –
lighting, rendering, shading. On Dino, we were still doing spherical harmonics and special shadow maps. Now, we’re going to raytracing.

“We felt like we were a little behind the curve,” May continues. “But the good thing is that now we’re right on the cusp, doing bi-directional pathtracing for the caustics. And, we’re doing some work with volumes to make a large number of volumes very efficient.” 

A de-noising filter developed by Disney Research and Disney Animation for use with Hyperion on Big Hero Six helped reduce computation time.

“All pathtracers exhibit noise, and to eliminate it would take an enormous amount of computation,” May says. “We have a real advantage in that we’re part of a bigger company that includes Disney Research, Disney Animation, and Industrial Light & Magic.” Now, others can now take advantage of that technology, too, which is available as a program called Denoiser with RenderMan.

Déjà vu All Over Again

Sometimes, though, the new technology needed to comply with an older aesthetic. When the fish swim in a reef that replicates the environment from the first film, the lighters re-created techniques they had used a decade ago.

“We forced a physically--based renderer to do something it didn’t want to do,” Megibben says. “Some of the engineers didn’t want it to. But, we needed the reef to be familiar and safe. When we’re in the MLI, we played with light and shadow, and the scenes have more contrast. We use backlighting and leave things in shadow. The reef is high key, almost comedic. It was a lot of fun to have two styles to play with between the two environments.”

With any sequel, the production crew has the problem of respecting the first film and expanding it to take advantage of tools and ideas they didn’t have before. And so, too, the writer and director.

“The best thing about this film was reuniting with the people I had worked with,” Stanton says. (Stanton had slipped away from Pixar to write and direct the 2012 live-action film John Carter.)

“But also, to be honest,” he adds, “it was learning new stuff about the characters. It was like being with a cousin and hearing stories I’d never heard before.” 

But, these characters weren’t just cousins, as he realized in one brilliant moment.

“It happened during our first scoring session,” Stanton says. “I’m watching a finished section. The music is on. And there’s a little separation, a rare moment. It was almost like looking at your kids the way the rest of the world sees them. It was the Nemo cue, the one moment in this film when we reference the first movie. I thought, ‘Holy crap. I remember when I came up with him. With her.’ I remembered the mundane office. These are characters everyone knows, but I had forgotten they came from me. It was profound.”   

Barbara Robertson (BarbaraRR@comcast.net) is an award-winning writer and a contributing editor forCGW.