We all know how unlife-like our water-bunnies looked when we rendered them from individual particles, or “metaballs.” But could you imagine if we had to render an animation of a cute little water-bunny hopping through a field? Or something even more complex like fire?

For more intricate objects such as water, using the particle method can leave the image choppy and grainy due since the metaballs can’t be infinitely small. The level set method is an alternative process to render images which models the liquid as a smooth surface. That method however, does have its drawbacks in that the technique begins to fail when the liquid becomes too small and ends up “under-resolved”.

To solve these problems, a computer science associate professor at Stanford, Ron Fedkiw, designed a novel algorithm combining the two methods named the Hybrid Particle Level Set Method (he must have put a lot of work into that title…). The new method employs the two other methods in appropriate situation, flawlessly switching back and forth.

Hollywood producers have used Fedkiw’s algorithm in movies since 2002 to create computer-generated liquids such as the liquid terminator in Terminator 3, the dragon’s fire-breath in Harry Potter 5, and the turbulent seas in the Pirates of the Caribbean trilogy. All of those achievements have rightfully earned Fedkiw a Scientific and Technical Academy Award.

http://www.sciencedaily.com/releases/2008/01/080126100827.htm

http://physbam.stanford.edu/~fedkiw/papers/stanford2001-04.pdf