Computer Graphics and Movies: Who Can You Trust?

If you can't believe fiction, what can you believe? Thanks to computers, two movies -- "Poseidon" and "Pirates of the Caribbean: Dead Man's Chest" -- nominated for a special effects Oscar at this year's Academy Award benefited from heavy numerical simulation, at least according to Ron Fedkiw, an assistant professor of computer science at Stanford University and consultant to Industrial Light and Magic.

In a presentation at the annual meeting of the American Association for the Advancement of Science, Fedkiw took film lovers behind the scenes of today's movies in his discussions of physics-based simulations the lend realism to to fantasy.

"It is an exhaustive task to prescribe the motion of every degree of freedom in a piece of clothing or a crashing wave," says Fedkiw. "Since these motions are governed by physical processes, it can be difficult to make these phenomena appear natural. Thus, physically based simulation has become quite popular in the special effects industry. The same class of tools useful for computational fluid dynamics is also useful for sinking a ship on the big screen."

But until recently, computer graphics experts could run inferior algorithms on many processors, or run the best algorithm on only one processor. The problem is that many algorithms do not scale well to larger numbers of processors. But about a year and a half ago, Fedkiw figured out how to run a star algorithm on many processors, resulting in special effects and stunning realism.

These days, Fedkiw designs new algorithms for diverse applications including computational fluid dynamics and solid mechanics, computer graphics, computer vision, and computational biomechanics. The algorithms may rotate objects, simulate textures, generate reflections or mimic collisions. Or they may mathematically stitch together slices of a falling water drop, rising smoke wisp or flickering flame to weave realism into computer graphic images.

"The simulation of gases, liquids and combustion for scientific reasons quickly translates into the ability to make animations of smoke, water and fire," Fedkiw says. "Similar statements hold for soft biological tissues, muscles, fractures and other solid material problems. Once the scientific numerical simulations are worked out, interesting animations can be made shortly thereafter."

As an aside, I have to report that in a true-life brush-with-glory moment, I've actually seen -- not one -- but two real Oscars. The story goes like this: Years ago I was working for a computer-book publisher who had offices in the Fantasy Record building in Berkeley, California. Shlepping into the lobby on my way to lunch across the street at Juan's one day, the lobby was packed with people, ballons, and champagne. As luck would have it, Saul Zaentz and Milos Foreman also had offices and studios in the same building (Zaentz, in fact, owned the building which was referred to as "the house that Creedence built" because the band Creedence Clearwater Revival recorded their first hit record there.) The night before, Zaentz had just received that year's Best Picture Award for "Amadeus" and Foreman Best Director for the same movie. Having just returned from the Academy Awards, they were walking into the lobby as I was walking out. So I ended up holding the door for Zaentz and Foreman as they held the Oscars above their head -- and the packed lobby cheered. Come on, you really didn't think those ballons were for me?

Posted by Jon Erickson at 09:55 AM  Permalink