In Disney’s Tangled, Rapunzel’s hair is a character unto itself as it weaves through the scenery alternating between a weapon, clothing, background, and plot device. Far removed from other hair in CG movies, it showcases the work of Columbia University’s Eitan Grinspun, who is the focus of a new article on the New York Times about how he and his group have brought real physics into animation unlike anything before.
Mr. Grinspun’s crucial idea was to throw out the jury-rigged models instead of trying to improve upon them, as Apple did with its operating system when it abandoned DOS and command prompts. “The programming had to be rethought from the ground up,” he said. Instead of trying to force a system that was designed to simulate straight hair to produce curly hair too, for instance, Mr. Grinspun created a more sophisticated system that could do both.
