Movement by the numbers

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I like how my recent interviews have had a common theme- using art to portray movement.  In my last post I talked about the work of Nell Breyer, the neuroscientist/choreographer.  When I asked her if she saw a mathematical basis to movement, her answer was a pretty definitive “no”.  Here we have the opposite perspective.  Eitan Grinspun also represents movement for artistic purposes.  But for him, it’s all about numbers and formulas.

Grinspun might be the only man in show business who sees audience inattention as a sign of success. This a Columbia University computer scientist has  become animation studios’ go-to guy for animating film details like hair and clothing. Diverging from the usual computer geek stereotype, Grinspun’s more a fan of dramas than action films.  He wants movies to fully engage audiences in the
characters’ emotions. For that reason he focuses on making sure movie-goers don’t get distracted by fake looking visual details. He succeeds by letting numbers do the work of animators for studios like PIXAR and Disney.

Back in graduate school Grinspun became fascinated with the idea that all movement can be described by mathematical formulas. He’d throw a cowboy hat in the air over and over again to watch it fall. Then he’d figure out the formula to describe how it hit the ground. These days Grinspun’s algorithms for movement save animators from having to draw every strand of Rapunzel’s hair as she spins in a circle. Instead, they can enter the length and texture of the hair and the direction of its movement into one of Grinspun’s computer algorithms. The program then automatically generates the image of what twirling long thick wavy hair should look like. Talking about his career, Grinspun’s eyes widen with disbelief. He says he can’t believe how lucky he is to get to use the laws of physics to create beautiful films.

I interviewed Grinspun in early January.  Just how nice of a guy was he?  After an hour of interviewing him, I pressed the wrong button on my recorder and erased the entire interview.  Not only did he spend almost an hour trying to help me recover the file, when that didn’t work he insisted on letting me interview him all over again.  “I just see it as media training,” he assured me.  “Apparently I need a little more media training myself!” was all I could say.