Animating predator and prey fish interactions

Fish exhibit a wide variety of behavior, including swimming and schooling. Animating a school of fish is difficult because of the large number of fish and because a school of fish often swims in distinctive and coordinated patterns, particularly when they are attacked by a predator. Previous work in computer graphics has not provided satisfactory models to simulate the many distinctive interactions between a school of prey fish and their predator. In this paper, we present a fish school escape behavior model that can simulate 12 fish escape maneuvers identified in biological studies: compact, avoid, fast avoid, skitter, fountain, flash, ball, split, join, herd, vacuole, and hourglass. This behavior animation model can free an animator from dealing with the low-level animations but instead controls the fish behavior on a higher level by modifying a state machine and a small set of system parameters.