A whole surface approach to crowd simulation on arbitrary topologies

Recent crowd simulation algorithms do path planning on complex surfaces by breaking 3D surfaces into a series of 2.5D planes. This allows for path planning on surfaces that can be mapped from 3D to 2D without distortion, such as multistory buildings. However, the 2.5D approach does not handle path planning on curved surfaces such as spheres, asteroids, or insect colonies. Additionally, the 2.5D approach does not handle the complexity of dynamic obstacle avoidance when agents can walk on walls or ceilings. We propose novel path planning and obstacle avoidance algorithms that work on surfaces as a whole instead of breaking them into a 2.5D series of planes. Our "whole surfaceâ approach simulates crowds on both multistory structures and highly curved topologies without changing parameters. We validate our work on a suite of 30 different meshes, some with over 100,000 triangles, with crowds of 1,000 agents. Our algorithm always averaged more than 40 FPS with virtually no stalling.