The Visual Computer

, Volume 29, Issue 10, pp 1051–1062 | Cite as

Enhanced waypoint graph for surface and volumetric path planning in virtual worlds

  • Nicholas Mario Wardhana
  • Henry Johan
  • Hock Soon Seah
Original Article

Abstract

Our research focuses on the problem of path planning in 3D virtual world applications. The characters we consider are heterogeneous, as they have different sizes, and can perform surface or volumetric motion. In this paper, we propose an enhanced waypoint graph, which consists of point nodes equipped with radius, as well as edges connecting those nodes. Each edge is labeled with the motion type it can support. Given a polygon soup representation of a virtual world, the proposed algorithm starts by subdividing the virtual world into regions. This enables us to process large virtual worlds. Each region is then locally voxelized, one at a time. Two kinds of waypoints are generated: local waypoints using corner detection on the voxelization, and border waypoints at the region boundary. Waypoints are then sparsely connected to form a local waypoint graph, and local graphs are finally connected via the border waypoints to create the final global enhanced waypoint graph. To plan paths between arbitrary points using this graph, the points are connected to the graph using nearest neighbor search and traversability test, then Dijkstra/A* algorithm is used to calculate the final path, taking into account the appropriate size and motion type.

Keywords

Path planning Automatic waypoint graph generation Heterogeneous characters Surface and volumetric motions Virtual worlds 

Notes

Acknowledgements

Our sincere gratitude goes to Quah Chee Kwang, Anthony Chansavang, and Budianto Tandianus for the fruitful personal discussions. The small outdoor scene as well as the two-story house models were created by Max Lim Tze Yuen, whereas Kampong Glam were created by the Media Development Authority (MDA) Singapore. These models are used in this research with permissions. This research is supported in part by the Ministry of Education Singapore, Academic Research Fund (AcRF) Tier 1 for project “Volumetric Path Planning in Real-Time 3D Virtual Environments”.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Nicholas Mario Wardhana
    • 1
  • Henry Johan
    • 2
  • Hock Soon Seah
    • 2
  1. 1.gameLAB, c/o School of Computer EngineeringNanyang Technological UniversitySingaporeSingapore
  2. 2.School of Computer EngineeringSingaporeSingapore

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