The Physics Of “Brave”‘s Curly Red Mane Brings Hair-Raising Animation to Life!

The one thing you can depend on with Pixar is that they will continually up the visual ante in their film.  For their latest film, Brave, Pixar has taken on the task of taming the wild red mane of Merida, a princess in the Scottish Highlands as willful and troublesome as her head of incredible red curls.  As it turns out, Pixar had to invent a system to depict Merida’s stubborn curly hair.  Forget the beautiful balloon house from Up, Merida’s mop is Pixar’s crowning achievement. 

“I have become obsessed with curly hair.  It is truly fascinating; curly hair defies physics in the way it moves and behaves,” said Claudia Chung, the simulation supervisor who worked on Brave‘s wild mane.  ”We used 1,500 hand-placed, sculpted individual curls.  There is this weird paradox where a ‘spring’ of hair needs to remain stiff in order to hold its curl, but it also has to remain soft in its movement.”  Added Chung, “It took us almost three years to get the final look for her hair, and we spent two months working on the scene where Merida removes her hood and you see the full volume of her hair.  When I first saw the storyboards for ‘Brave,’ I drooled; I had no idea how I was going to do it, but I knew this was going to be so much fun.”

How they did it was a revolutionary new system for animating hair on film.  Dubbed a core curve and points, the computer model looks like a beaded necklace.  As Merida moves, her hair moves with her, but retains its general shape.  Her curls, a mass of individual springs of hair ranging from tight pincurls to fat wavy spirals, came from two distinct sources.  One of these sources was a curly wig the staff members took turns wearing; the other was an actually curly-haired Pixar employee, who found herself getting soaked down by the team so they could study how curly hair looks and moves wet.

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