Maintaining Extremal Points and Its Applications to Deciding Optimal Orientations

  • Sang Won Bae
  • Chunseok Lee
  • Hee-Kap Ahn
  • Sunghee Choi
  • Kyung-Yong Chwa
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4835)


We consider two non-convex enclosing shapes with the minimum area; the L-shape and the quadrant hull. This paper proposes efficient algorithms computing each of two shapes enclosing a set of points with the minimum area over all orientations. The algorithms run in time quadratic in the number of given points by efficiently maintaining the set of extremal points.


Convex Hull Extremal Point Event Orientation Optimal Orientation Partition Tree 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Sang Won Bae
    • 1
  • Chunseok Lee
    • 1
  • Hee-Kap Ahn
    • 2
  • Sunghee Choi
    • 1
  • Kyung-Yong Chwa
    • 1
  1. 1.Division of Computer Science, KAIST, DaejeonKorea
  2. 2.Department of Computer Science and Engineering, POSTECH, PohangKorea

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