We may not have realized it at the time, but during the 1990s, Hollywood movies were infiltrated by a new presence that outshined even the biggest screen stars: Images created on computers became the main draws for movies like Jurassic Park, Toy Story, The Matrix, and Star Wars Episode I: The Phantom Menace. Since then, the prominence of computer graphics (CG) has become expected and unremarkable, as much a part of the multiplex experience as ugly carpeting and reminders to silence your cell phone.
CG began its takeover once the art and technology had distinct advantages over other ways to create images. At the same time, it still has weak points. Realistic human faces are notoriously hard to recreate, for instance. Animators have spent untold thousands of hours trying to get hair to look just right. And the movement of fluids, particularly turbulent fluids, continues to bedevil movie artists.
One of the particular challenges of simulating fluids is that requires a deep technical understanding of how fluids behave (which is hard even for experts in the field). So effects houses have raided universities and aerospace companies looking for scientists who understand how fluids work. A recent, excellent profile by Richard Verrier in the Los Angeles Times focuses on Ron Henderson, a former academic engineer who now engineers pixels:
Henderson could easily have been preparing a lesson at Caltech, where he once was a faculty member. Instead, he was at DreamWorks Animation’s Tuscany-style campus, doing his part to bridge the divide between art and science.
Verrier reports that DreamWorks’ R&D group has 120 members with master’s and doctorate degrees, not only in engineering but also chemistry, cognitive science, and astrophysics.
“The physics behind what’s happening in these movies is incredibly complicated,” said Paul Debevec, a computer scientist and chief visual officer at the USC Institute for Creative Technologies. “You need real scientists to understand what’s going on.”
One of Henderson’s recent challenges was simulating the turbulent flow on bubble-like spheres inhabited by aliens for the upcoming movie Home, reports Verrier. He ended up adapting a model of another system where turbulent fluids roil around a sphere: a weather-forecasting program.
Over the decades that scientists have wrestled with these problems, they have created a large group of tools like the one Henderson made for bubbly spheres—powerful algorithms that make it easier for computers to simulate the complicated world of fluid dynamics. (Like all scientists, the technical people working on movies are standing on the shoulders of giants.) Earlier this year, Henderson himself won a Technical Achievement Academy Award for FLUX, a program he created to simulate things like smoke, fire, and dust for movies including Monsters Vs. Aliens and Puss in Boots.
Combined with the constant improvements in computers that create digital animations, the new software has not only made feature films look better, but has also opened up turbulence to the people: Individual animators can now create their own realistic-looking simulations of fluids, on their own personal computers. They upload many of these videos to the Web, demonstrating new techniques, looking for feedback, showing off their skills. (See some of the best at the top of this post and below.) A creative vision that was once a challenge for even the most powerful workstations may now be an experiment, a proof of concept, a lesson for a curious autodidact.
Amos Zeeberg is Nautilus’ digital editor.