Computer Science and Engineering, Department of


Date of this Version



Constraint Systems Laboratory

Department of Computer Science and Engineering
University of Nebraska-Lincoln


A method is presented for animating herds of animals that can follow terrain while being efficient enough to run in real-time. This method involves making simple modifications to Reynolds’ agent-based flocking algorithm. The modifications use only local properties of the terrain, and thus have low complexity. This method focuses on using terrain that can be described as an elevation grid, but it may be extendible to arbitrary terrain. The flocking algorithm with these modifications produces naturally behaving herds that follow the terrain. They will swerve around hills and attempt to follow paths that reduce energy expenditure. The terrain-following rule added to the flocking algorithm has a constant parameter that can be adjusted to produce different behaviors. Empirical analysis shows how this parameter affects energy expenditure of the animals while traveling over the terrain.