What you see is Merida, the heroine of Disney and Pixar's Brave, reclining in a forest meadow, the wind rustling the grass and her curly, poppy red hair, light filtering softly through the trees. What Tony DeRose sees is a multitude of mathematical coordinates — each of the thousands of blades of grass a parabola, animated by moving points along its arc; each strand of Merida's hair given body by a mass spring system of equations; the natural movement of her dress calculated by a simulation program.
DeRose, senior scientist and lead of the Research Group at Pixar Animation Studios, gave members of the Bucknell University community and the surrounding region insight into that world of numbers, coordinates and equations during a Sept. 18 talk, "Math in the Movies," at the Campus Theatre in downtown Lewisburg. The event was sponsored by the Departments of Mathematics and Computer Science, the Film/Media Studies Program and the University Lectureship Committee.
"In computer graphics, we have to bridge the gap between the way artists think about things, which is in terms of shapes and images, and the way computers think about things, which is in terms of numbers, equations and algebra," DeRose said.
DeRose was a major contributor to Geri's Game, the 1997 Academy Award winner for best animated short film that pioneered techniques used in virtually all films employing computer animation since, from Toy Story to Transformers. He has also contributed to a number of Pixar box office hits, including The Incredibles, Finding Nemo and Monsters, Inc.
His speech demonstrated the computer tools Pixar animators use to bring stories to life, touched on the mathematical theories that make those tools work, and provided an overview of the process — typically about four years — of taking a story from concept to finished feature film.
"It's amazing, the whole process it takes to create it all," said Johnny Shen, a first-year math major. "I want to learn more about the math procedures behind it."
Fitting for a mathematician, DeRose's speech was filled with mind-blowing numbers. Creating an animated storyboard, or story reel, takes two years and comprises up to 200,000 hand- and computer-drawn sketches, DeRose said, and a single character can be controlled by as many as 1,500 virtual puppet strings, 300 in the face alone. By way of contrast, about 30 muscles control the motion of the human face.
"We're about 10 times better than real," he joked.
But for all the computer wizardry on display at the event, DeRose also reminded the audience that each film his company produces "begins with story."
"If the story isn't working, no amount of beautiful computer graphics can fix it," he said.