Simple algorithms for searching a polygon with flashlights

doi:10.1016/S0020-0190(01)00235-6

Information Processing Letters

Volume 81, Issue 5, 16 March 2002, Pages 265-270

https://doi.org/10.1016/S0020-0190(01)00235-6 Get rights and content

Abstract

The k-searcher is a mobile guard whose visibility is limited to k rays emanating from her position, where the direction of each ray can be changed continuously with bounded angular rotation speed. Given a polygonal region P, is it possible for the k-searcher to eventually see a mobile intruder that is arbitrarily faster than the searcher within P? We present O(n²)-time algorithms for constructing a search schedule of the 1-searcher and the 2-searcher, respectively. Our framework for the 1-searcher can be viewed as a modification of that of LaValle et al. [Proc. 16th ACM Symp. on Computational Geometry, 2000, pp. 260–269] and is naturally extended for the 2-searcher.

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^☆: Supported by KOSEF (Korea Science and Engineering Foundation) under grant 98-0102-07-01-3.

¹: This work was done while the author was affiliated with Max-Planck-Institut für Informatik, Saarbrücken, Germany.

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Simple algorithms for searching a polygon with flashlights☆

Abstract

Searching for a mobile intruder in a corridor — The open edge variant of the polygon search problem

Internat. J. Comput. Geom. Appl.

Sweeping simple polygons with a chain of guards

Linear-time algorithms for visibility and shortest path problems inside triangulated simple polygon

Algorithmica

A visibility-based pursuit-evasion problem

Internat. J. Comput. Geom. Appl.

The two guards problem

Internat. J. Comput. Geom. Appl.