Claudia Chung Brings Realism to Pixar Heroine

When audiences watch Pixar’s Brave, they won’t be thinking about Merida’s hair or her uncouth father’s clothing. They’ll likely be chortling at the story of a tomboy princess who can outshoot, outride and outfight the realm’s most eligible bachelors.

But if, at the end of the animated feature, they think to marvel at the remarkable naturalism of the characters that populate Merida’s obviously simulated old Scotland, they might stick around long enough to note that the film’s Simulation Supervisor is Claudia Chung.

“The hope is that when the audience watches the film, all they immerse themselves in is the story, and the adventure,” said Chung.

“We know as humans walking around with clothes and hair, we know how clothes should move, and we have this sense when it actually doesn’t move right. When it looks strange, a little bit floaty or weird, the audience can pop out of the story. They say, ‘Why is that skirt flipping up when he jumps off the horse?’ That kind of thing is what we definitely don’t want to happen.”

Pixar has been pushing the technical barriers of animation with each film. In Cars 2 it overcame the challenge of lighting the ocean and capturing its reflections off metal. In Finding Nemo it struggled to achieve the underwater effects. In Up it managed to make thousands of soaring balloons behave like real balloons. In Toy Story 3 it added realistic lighting effects to the rolling and pitching of plastic bags.

But only in its 13th animated feature did Pixar have the technological confidence to attempt a main character with a full head of long curly hair that bounces and flows with every close-up action sequence. With carrot-topped Merida the studio has overcome by far its most daunting challenge to date — a tomboy that sends her long hair every which way in numerous action sequences.

That technological achievement is embodied to a large extent in Pixar’s new hair simulation software named Taz after the cartoon character Tasmanian Devil. The software was used not only for Merida’s hair but also to render the fur of several bears central to Brave. The studio’s old software had been up to depicting the hair of secondary characters in earlier efforts but not up to convincing audiences that a female action figure didn’t have unnaturally stiff hair.

It took the studio a year to make the fine adjustments needed to let Taz observe all the laws of physics with respect to Merida’s curly locks, the fur on Merida’s galloping steed and the fold and flop of the multi-layered clothing worn by Merida’s father Fergus.

“For cloth, that’s as hard as it’s ever gotten for Pixar, if not the industry,” Chung said.

To add to the complexity of the software’s rendering computations, some scenes involved action in a river. Making splashes look naturalistic and even capturing the wetting of Merida’s dress required intensive computing that could take several days, according to Steve May, Pixar CTO and the film’s technical consultant. He intends to refine Taz even more to give animators more control over individual strands of hair that splay.

“We never compromise at Pixar to make things cheaper,” said Chung. “The idea is that everyone is in it to make a great film and be artistic.”

Claudia Chung graduated with a computer science degree from UC Berkeley in 2002. She began her career at Pixar as a computer graphics artist on Finding Nemo (2003), then progressed to technical director on The Incredibles (2004) and simulation artist and tailoring artist on Ratatouille (2007).

“I was very technical when I came to Pixar,” she recalls. “When I started on Ratatouille that’s when I went over to the tailoring side of things and it was actually a really hard process, a leap for me. It looked terrible when I started. And I was like, ‘Claudia, it’s time for you to take a sewing class.’”