Inside the building is a data center full of humming servers — double the size that the company used in the past — that would be considered one of the top 25 supercomputers in the world. The 2,000 computers have more than 24,000 cores. The data center is like the beating heart behind the movie’s technology.
Even with all of that computing might, it still takes 29 hours to render a single frame of Monsters University, according to supervising technical director Sanjay Bakshi.
Rendering means that the computers build the 3D world in its full colors as the scene is meant to be viewed in a theater. The machines create the frame and it is then captured as one of thousands of frames in the movie. When you watch the movie, you see anywhere from 24 frames to 60 frames per second.
All told, it has taken more than 100 million CPU hours to render the film in its final form. If you used one CPU to do the job, it would have taken about 10,000 years to finish. With all of those CPUs that Pixar did have, it took a couple of years to render.
The reason it took so much more computing power is that the eyes of the audience have grown. Something that looked spectacular 12 years ago, like the fur on the monster Sully, doesn’t look so great today. Sully now has 5.5 million individual hairs in his fur, compared to a fifth of that in the original film. In Monsters Inc., it was impressive to create one simulated garment with realistic, cloth-like behavior: the shirt on the character Boo. The new film has 127 simulated garments, and the hair and cloth simulator had to be re-coded from scratch, said Christine Waggoner, the simulation supervisor on the film.
“We had to simulate blankets, sheets, mattresses and pillows,” Waggoner said. “In a jacket simulation, a jacket is removed from the shoulder and it has to appear natural as it moves. We even simulated the zippers on the backpacks. That’s Pixar’s level of attention to detail.”
When you look at Monsters University, you’ll notice effects like the flag swaying in the wind. But you’ll also notice the blades of grass in the plaza, the swaying of the trees, the large numbers of student monsters roaming all over the school, and the lighting and shadows everywhere.