Guarding Fat Polygons and Triangulating Guarded Polygons

نویسندگان

  • G. Aloupis
  • P. Bose
  • V. Dujmovic
  • S. Langerman
  • B. Speckmann
چکیده

In this paper we study three related problems: (i) Given a fat polygon P , we show how to find a set G of points in P such that every point on the boundary of P sees at least one point of G. The set G is said to guard the boundary of P and its cardinality depends on the shape parameters of P . Fat polygons are often used to model more realistic inputs. (ii) Given k points that guard the boundary of P , we show how to compute O(k) points that guard the interior of P . (iii) Given k points that guard P , we provide two simple O(kn) time algorithms to triangulate P : one that triangulates the polygon when the guards are given as input and the other slightly more complicated algorithm that triangulates the polygon when the guards are not given.

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تاریخ انتشار 2007