An Approximation Algorithm for the Art Gallery Problem

Authors Édouard Bonnet, Tillmann Miltzow

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Édouard Bonnet
Tillmann Miltzow

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Édouard Bonnet and Tillmann Miltzow. An Approximation Algorithm for the Art Gallery Problem. In 33rd International Symposium on Computational Geometry (SoCG 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 77, pp. 20:1-20:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)


Given a simple polygon P on n vertices, two points x, y in P are said to be visible to each other if the line segment between x and y is contained in P. The Point Guard Art Gallery problem asks for a minimum-size set S such that every point in P is visible from a point in S. The set S is referred to as guards. Assuming integer coordinates and a specific general position on the vertices of P, we present the first O(log OPT)-approximation algorithm for the point guard problem. This algorithm combines ideas in papers of Efrat and Har-Peled and Deshpande et al. We also point out a mistake in the latter.
  • computational geometry
  • art gallery
  • approximation algorithm


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