ETRI Journal

Electronics and Telecommunications Research Institute (한국전자통신연구원)
권호 표지
DOI QR코드

DOI QR Code

Space-Time Warp Curve for Synthesizing Multi-character Motions

  • Sung, Mankyu (Department of Game and Mobile Contents, Keimyung University) ;
  • Choi, Gyu Sang (Department of Information and Communication Engineering, Yeungnam University)
  • Received : 2016.09.20
  • Accepted : 2017.05.22
  • Published : 2017.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

This paper introduces a new motion-synthesis technique for animating multiple characters. At a high level, we introduce a hub-sub-control-point scheme that automatically generates many different spline curves from a user scribble. Then, each spline curve becomes a trajectory along which a 3D character moves. Based on the given curves, our algorithm synthesizes motions using a cyclic motion. In this process, space-time warp curves, which are time-warp curves, are embedded in the 3D environment to control the speed of the motions. Since the space-time warp curve represents a trajectory over the time domain, it enables us to verify whether the trajectory causes any collisions between characters by simply checking whether two space-time warp curves intersect. In addition, it is possible to edit space-time warp curves at run time to change the speed of the characters. We use several experiments to demonstrate that the proposed algorithm can efficiently synthesize a group of character motions. Our method creates collision-avoiding trajectories ten times faster than those created manually.

Keywords

References

  1. C.W. Reynold, "Steering Behaviors for Autonomous Character," in Proc. Game Developers Conf., San Jose, CA, USA, 1999, pp. 763-782.
  2. D. Helbing and P. Molnar, "Social Force Model for Pedestrian Dynamics," Phys. Rev. E, vol. 51, Jan. 1995.
  3. A. Treuille, S. Cooper, and Z. Popovic, "Continuum Crowds," ACM Trans. Graph, vol. 25, no. 3, July 2006, pp. 1160-1168. https://doi.org/10.1145/1141911.1142008
  4. T. Kwon et al., "Group Motion Editing," ACM Trans. Graph, vol. 27, no. 3, Aug. 2008, pp. 80:1-80:8.
  5. M. Kim et al., "Synchronized Multi-character Motion Editing," ACM Trans. Graph., vol. 28. no. 3, Aug. 2009, pp. 79:1-79:9.
  6. J. Kim et al, "Interactive Manipulation of Large-Scale Crowd Animation," ACM Trans. Graph., vol. 33, no. 4, July 2014, pp. 83:1-83:10.
  7. H.P.H. Shum, T. Komura, and S. Yamazaki, "Simulating Multiple Character Interactions with Collaborative and Adversarial Goals," IEEE Trans. Vis. Comput. Graph., vol. 18, no. 5, May 2012, pp. 741-752. https://doi.org/10.1109/TVCG.2010.257
  8. A. Barnett, H.P.H. Shum, and T. Komura, "Coordinated Crowd Simulation with Topological Scene Analysis," J. Comput. Graph. Forum, vol. 35, no. 6, Oct. 2016, pp. 120-132.
  9. B. Yersin et al, "Crowd Patches: Populating Large-Scale Virtual Environment for Real-Time Applications," Proc. Symp. Interactive 3D Graph. Games, Boston, MA, USA, Feb. 27-Mar. 1, 2009, pp. 207-214.
  10. P. Shirley, M. Ashikhmin, and S. marschner, Fundamentals of Computer Graphics, 3rd Edition, Boca Raton, FL, USA: CRC Press, 2009.
  11. S. Leon, Linear Algebra with Applications, 3rd Edition, London, UK: MacMillan Publishers, 1990.
  12. M. Gleicher, "Motion Path Editing," Proc. Symp. Interactive 3D Graph., Triangle Pk, NC, USA, Mar. 19-21, 2001, pp. 195-202.
  13. L. Kovar, J. Schreiner, and M. Gleicher, "FootSkating Cleanup for Motion Capture Editing," Proc. ACM SIGGGRAPH/Eurograph. Symp. Comput. Animation, San Antonio, TX, USA, July 21-22, 2002, pp. 97-104.
  14. BioVision Hierarchy (BVH) Format, Accessed 2016. http://www.character-studio.net/bvh_file_specification.htm