GPU Accelerated Path-Planning for Multi-agents in Virtual Environments

Many games are populated by synthetic humanoid actors that act as autonomous agents. The animation of humanoids in real-time applications is yet a challenge if the problem involves attaining a precise location in a virtual world (path-planning), and moving realistically according to its own personality, intentions and mood (motion planning). In this paper we present a strategy to implement – using CUDA on GPU – a path planner that produces natural steering behaviors for virtual humans using a numerical solution for boundary value problems. The planner is based on the potential field formalism that allows synthetic actors to move negotiating space, avoiding collisions, and attaining goals, while producing very individual paths. The individuality of each character can be set by changing its inner field parameters leading to a broad range of possible behaviors without jeopardizing its performance. With our GPU-based strategy we achieve a speed up to 56 times the previous implementation, allowing its use in situations with a large number of autonomous characters, which is commonly found in games.