Planning bipedal character locomotion in virtual worlds

Abstract: This paper presents a locomotion system suitable for interactive usethat can plan realistic paths for small numbers of bipedal charactersin virtual worlds. Earlier approaches are extended by allowing animationsto be arbitrarily blended to increase the range of motions thatthe character can produce and our system also achieves greater performancecompared to the earlier approaches. The system uses a graphof valid footprints in the world in which is searched for a path thatthe character should traverse. The resulting sequence of footprints aresmoothed and refined to make them more similar to the character’soriginal animations. To make the motion smoother the curvature andother parameters of the path are estimated and those estimates areused to interpolate between different sets of similar animation clips. Asthe system is based on footprints it allows characters to navigate evenacross regions which are not directly connected, for example by jumpingover the gaps between disconnected regions. We have implementedthe system in C# using the Unity Game Engine and we evaluate it bymaking the character perform various actions such as walking, runningand jumping and study the visual result.Accompanying material can be found at http://arongranberg.com/research/thesis2017.