7 - Project: Particle Effects

Summary

Computer animators have always sought to push boundaries and create impressive, realistic visual effects, but some processes are too demanding to model exactly. Effects like fire, smoke, and water have complex fluid dynamics and amorphous boundaries that are hard to recreate with standard physical calculations. Instead, animators might turn to another approach to create these effects: particle systems. Bill Reeves, a graphics researcher and animator, began experimenting with particle-based effects in the early 1980s while making movies at Lucasfilm. For a scene in Star Trek II: The Wrath of Khan (1982), he needed to create an image of explosive fire spreading across the entire surface of a planet. Reeves used thousands of independent particles, each one representing a tiny piece of fire (Reeves, 1983). The fire particles were created semi-randomly, with attributes for their 3D positions, velocities, and colors. Reeves’ model governed how particles appeared, moved, and interacted to create a realistic effect that could be rendered on an early 1980s computer. Reeves would go on to work on other Lucasfilm productions, including Return of the Jedi (1983), before joining Pixar, where his credits include Toy Story (1995) and Finding Nemo (2003).