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A hidden guard set $ G $ is a set of point guards in polygon $ P $ that all points of the polygon are visible from some guards in $ G $ under the constraint that no two guards may see each other. In this paper, we consider the problem for…

Computational Geometry · Computer Science 2017-08-22 Hamid Hoorfar , Alireza Bagheri

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

The purpose of the current study is to investigate a special case of art gallery problem, namely Sculpture Garden Problem. In the said problem, for a given polygon $P$, the ultimate goal is to place the minimum number of guards to define…

Computational Geometry · Computer Science 2021-07-20 Marzieh Eskandari , Bahram Sadeghi Bigham

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

A polygonal art gallery can be observed by guards placed at one third of its corners. However, the strategy of placing guards at every third corner does not work for all art galleries. In this note, we provide an example of a nine-sided art…

Combinatorics · Mathematics 2019-08-06 Ralph Morrison

We study the problem of guarding orthogonal art galleries with horizontal mobile guards (alternatively, vertical) and point guards, using "rectangular vision". We prove a sharp bound on the minimum number of point guards required to cover…

Combinatorics · Mathematics 2019-11-07 Ervin Győri , Tamás Róbert Mezei

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

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 examine the Art Gallery Problem with Edge Guards. We present a heuristic algorithm to arrange edge guards to guard only the inward side of the walls of any N-vertex simple polygonal gallery using at most roof (N/4) edge guards - a…

Metric Geometry · Mathematics 2012-07-17 R. Nandakumar

A sliding camera inside an orthogonal polygon $P$ is a point guard that travels back and forth along an orthogonal line segment $\gamma$ in $P$. The sliding camera $g$ can see a point $p$ in $P$ if the perpendicular from $p$ onto $\gamma$…

Computational Geometry · Computer Science 2016-04-26 Therese Biedl , Timothy M. Chan , Stephanie Lee , Saeed Mehrabi , Fabrizio Montecchiani , Hamideh Vosoughpour

Art Gallery is a fundamental visibility problem in Computational Geometry. The input consists of a simple polygon P, (possibly infinite) sets G and C of points within P, and an integer k; the task is to decide if at most k guards can be…

Computational Geometry · Computer Science 2020-03-18 Akanksha Agrawal , Kristine V. K. Knudsen , Daniel Lokshtanov , Saket Saurabh , Meirav Zehavi

Guarding a polygon with few guards is an old and well-studied problem in computational geometry. Here we consider the following variant: We assume that the polygon is orthogonal and thin in some sense, and we consider a point $p$ to guard a…

Computational Geometry · Computer Science 2016-04-26 Therese Biedl , Saeed Mehrabi

We present two new versions of the chromatic art gallery problem that can improve upper bound of the required colors pretty well. In our version, we employ restricted angle guards so that these modern guards can visit $\alpha$-degree of…

Computational Geometry · Computer Science 2017-11-21 Hamid Hoorfar

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

We study the problem of placing a set $T$ of broadcast towers in a simple polygon $P$ in order for any point to locate itself in the interior of $P$. Let $V(p)$ denote the visibility polygon of a point $p$, as the set of all points $q \in…

Computational Geometry · Computer Science 2018-11-30 Prosenjit Bose , Jean-Lou De Carufel , Alina Shaikhet , Michiel Smid

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

We resolve the complexity of the point-boundary variant of the art gallery problem, showing that it is $\exists\mathbb{R}$-complete, meaning that it is equivalent under polynomial time reductions to deciding whether a system of polynomial…

Computational Geometry · Computer Science 2025-04-11 Jack Stade

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

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 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