One of the keys to Pixar's ability to do what it does is the giant, powerful render farm located in its main headquarters building here. This is serious computing power, and on "Cars 2," it required an average of 11.5 hours to render each frame.
But some sequences were especially complex, particularly those involving ray tracing--which involves simulating light hitting surfaces, essentially "trying to simulate photons." And as a result, a huge amount of computing power was needed to process frames that took as much as 80 or 90 hours to render, Shah said. And that meant that the studio "bulked up our render farm."
He said that Pixar had to triple its size, and today, the render farm features 12,500 cores on Dell render blades. As well, the file servers, network backbone, and every other piece of the computing puzzle was boosted in order to handle the making of "Cars 2."
But Pixar's next films are sure to tax even that computing infrastructure, Shah said. Those movies will benefit from the scaling out done for "Cars 2," but the next projects will surely offer up their own creative challenges that could force the studio to expand the render farm yet again. Shah said things like human characters and their skin, hair, and cloth are sure to stretch even today's farm to its limits.