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Given a closed simple polygon $P$, we say two points $p,q$ see each other if the segment $pq$ is fully contained in $P$. The art gallery problem seeks a minimum size set $G\subset P$ of guards that sees $P$ completely. The only currently…

Computational Geometry · Computer Science 2024-08-07 Simon Hengeveld , Tillmann Miltzow

We study the classical Art Gallery Problem first proposed by Klee in 1973 from a mobile multi-agents perspective. Specifically, we require an optimally small number of agents (also called guards) to navigate and position themselves in the…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-05-13 Barath Ashok , John Augustine , Aditya Mehekare , Sridhar Ragupathi , Srikkanth Ramachandran , Suman Sourav

We study the Dispersive Art Gallery Problem with vertex guards: Given a polygon $\mathcal{P}$, with pairwise geodesic Euclidean vertex distance of at least $1$, and a rational number $\ell$; decide whether there is a set of vertex guards…

Computational Geometry · Computer Science 2024-06-11 Sándor P. Fekete , Joseph S. B. Mitchell , Christian Rieck , Christian Scheffer , Christiane Schmidt

Given a simple polygon $\cal P$, in the Art Gallery problem, the goal is to find the minimum number of guards needed to cover the entire $\cal P$, where a guard is a point and can see another point $q$ when $\overline{pq}$ does not cross…

Computational Geometry · Computer Science 2021-08-26 Arash Vaezi , Bodhayan Roy , Mohammad Ghodsi

We prove that every simply connected orthogonal polygon of $n$ vertices can be partitioned into $\left\lfloor\frac{3 n +4}{16}\right\rfloor$ (simply connected) orthogonal polygons of at most 8 vertices. It yields a new and shorter proof of…

Combinatorics · Mathematics 2017-06-27 Ervin Győri , Tamás Róbert Mezei

We are interested in the problem of guarding simple orthogonal polygons with the minimum number of $ r $-guards. The interior point $ p $ belongs an orthogonal polygon $ P $ is visible from $ r $-guard $ g $, if the minimum area rectangle…

Computational Geometry · Computer Science 2017-09-14 Hamid Hoorfar , Alireza Bagheri

In the problem "Localization and trilateration with the minimum number of landmarks", we faced the 3-Guard and classic Art Gallery Problems. The goal of the art gallery problem is to find the minimum number of guards within a simple polygon…

Computational Geometry · Computer Science 2025-03-14 Bahram Sadeghi Bigham , Sahar Badri , Nazanin Padkan

This paper focuses on a variation of the Art Gallery problem that considers open edge guards and open mobile guards. A mobile guard can be placed on edges and diagonals of a polygon, and the "open" prefix means that the endpoints of such…

Computational Geometry · Computer Science 2013-06-20 Antonio Leslie Bajuelos , Santiago Canales , Gregorio Hernández , Mafalda Martins , Inês Matos

Victor Klee introduce the art gallery problem during a conference in Stanford in August 1976 with that question: "How many guards are required to guard an art gallery?" In 1987, Ghosh provided an approximation algorithm for vertex guards…

Computational Geometry · Computer Science 2022-03-04 Shiva Maleki , Ali Mohades

We will consider some extensions of the polygonal art gallery problem. In a recent paper Morrison has shown the smallest (9 sides) example of an art gallery that cannot be observed by guards placed in every third corner. Author also…

Computational Geometry · Computer Science 2019-09-20 Eryk Lipka

There exist many variants of guarding an orthogonal polygon in an orthogonal fashion: sometimes a guard can see an entire rectangle, or along a staircase, or along an orthogonal path with at most $k$ bends. In this paper, we study all these…

Computational Geometry · Computer Science 2017-06-08 Therese Biedl , Saeed Mehrabi

We study the Art Gallery Problem for face guards in polyhedral environments. The problem can be informally stated as: how many (not necessarily convex) windows should we place on the external walls of a dark building, in order to completely…

Computational Geometry · Computer Science 2014-04-22 Giovanni Viglietta

Let an orthogonal polyhedron be the union of a finite set of boxes in $\mathbb R^3$ (i.e., cuboids with edges parallel to the coordinate axes), whose surface is a connected 2-manifold. We study the NP-complete problem of guarding a…

Computational Geometry · Computer Science 2019-10-25 Giovanni Viglietta

The Art Gallery Problem (AGP) asks for placing a minimum number of stationary guards in a polygonal region P, such that all points in P are guarded. The problem is known to be NP-hard, and its inherent continuous structure (with both the…

Computational Geometry · Computer Science 2014-12-19 Sándor P. Fekete , Stephan Friedrichs , Alexander Kröller , Christiane Schmidt

We consider the problem of monitoring an art gallery modeled as a polygon, the edges of which are arcs of curves, with edge or mobile guards. Our focus is on piecewise-convex polygons, i.e., polygons that are locally convex, except possibly…

Computational Geometry · Computer Science 2011-03-01 Menelaos I. Karavelas

The art gallery problem enquires about the least number of guards that are sufficient to ensure that an art gallery, represented by a polygon $P$, is fully guarded. In 1998, the problems of finding the minimum number of point guards, vertex…

Computational Geometry · Computer Science 2016-05-03 Pritam Bhattacharya , Subir Kumar Ghosh , Bodhayan Roy

This paper addresses the problem of tracking mobile intruders in a polygonal environment. We assume that a team of diagonal guards is deployed inside the polygon to provide mobile coverage. First, we formulate the problem of tracking a…

Computational Geometry · Computer Science 2018-07-24 Guillermo J. Laguna , Sourabh Bhattacharya

Given a simple polygon $\cal P$, in the Art Gallery problem the goal is to find the minimum number of guards needed to cover the entire $\cal P$, where a guard is a point and can see another point $q$ when $\overline{pq}$ does not cross the…

Computational Geometry · Computer Science 2021-12-03 Arash Vaezi , Mohammad Ghodsi

We study the problem of colouring the vertices of a polygon, such that every viewer in it can see a unique colour. The goal is to minimise the number of colours used. This is also known as the conflict-free chromatic guarding problem with…

Computational Geometry · Computer Science 2020-04-07 Onur Çağırıcı , Subir Kumar Ghosh , Petr Hliněný , Bodhayan Roy

We present an optimal, linear-time algorithm for the following version of terrain guarding: given a 1.5D terrain and a horizontal line, place the minimum number of guards on the line to see all of the terrain. We prove that the cardinality…

Computational Geometry · Computer Science 2019-06-04 Ovidiu Daescu , Stephan Friedrichs , Hemant Malik , Valentin Polishchuk , Christiane Schmidt