English
Related papers

Related papers: Obstructing Visibilities with One Obstacle

200 papers

An obstacle representation of a graph $G$ consists of a set of polygonal obstacles and a drawing of $G$ as a visibility graph with respect to the obstacles: vertices are mapped to points and edges to straight-line segments such that each…

Computational Geometry · Computer Science 2025-02-18 Oksana Firman , Philipp Kindermann , Jonathan Klawitter , Boris Klemz , Felix Klesen , Alexander Wolff

An \emph{obstacle representation} of a graph consists of a set of polygonal obstacles and a distinct point for each vertex such that two points see each other if and only if the corresponding vertices are adjacent. Obstacle representations…

Computational Geometry · Computer Science 2013-06-14 Alexander Koch , Marcus Krug , Ignaz Rutter

An obstacle representation of a graph $G$ consists of a set of pairwise disjoint simply-connected closed regions and a one-to-one mapping of the vertices of $G$ to points such that two vertices are adjacent in $G$ if and only if the line…

Computational Geometry · Computer Science 2025-02-25 Martin Balko , Steven Chaplick , Robert Ganian , Siddharth Gupta , Michael Hoffmann , Pavel Valtr , Alexander Wolff

An obstacle representation of a graph $G$ is a set of points in the plane representing the vertices of $G$, together with a set of polygonal obstacles such that two vertices of $G$ are connected by an edge in $G$ if and only if the line…

Combinatorics · Mathematics 2017-07-18 Martin Balko , Josef Cibulka , Pavel Valtr

An obstacle representation of a graph G is a set of points on the plane together with a set of polygonal obstacles that determine a visibility graph isomorphic to G. The obstacle number of G is the minimum number of obstacles over all…

Discrete Mathematics · Computer Science 2015-03-17 János Pach , Deniz Sarioz

An \emph{obstacle representation} of a graph $G$ is a straight-line drawing of $G$ in the plane together with a collection of connected subsets of the plane, called \emph{obstacles}, that block all non-edges of $G$ while not blocking any of…

Given finitely many connected polygonal obstacles $O_1,\dots,O_k$ in the plane and a set $P$ of points in general position and not in any obstacle, the {\em visibility graph} of $P$ with obstacles $O_1,\dots,O_k$ is the (geometric) graph…

Combinatorics · Mathematics 2017-09-08 John Gimbel , Patrice Ossona de Mendez , Pavel Valtr

An obstacle representation of a graph is a mapping of the vertices onto points in the plane and a set of connected regions of the plane (called obstacles) such that the straight-line segment connecting the points corresponding to two…

Given a graph $G$, an {\em obstacle representation} of $G$ is a set of points in the plane representing the vertices of $G$, together with a set of connected obstacles such that two vertices of $G$ are joined by an edge if and only if the…

Combinatorics · Mathematics 2011-03-15 Padmini Mukkamala , János Pach , Dömötör Pálvölgyi

An obstacle representation of a plane graph G is V(G) together with a set of opaque polygonal obstacles such that G is the visibility graph on V(G) determined by the obstacles. We investigate the problem of computing an obstacle…

Computational Geometry · Computer Science 2011-08-15 Matthew P. Johnson , Deniz Sarioz

The grid obstacle representation, or alternately, $\ell_1$-obstacle representation of a graph $G=(V,E)$ is an injective function $f:V \rightarrow \mathbb{Z}^2$ and a set of point obstacles $\mathcal{O}$ on the grid points of $\mathbb{Z}^2$…

Computational Geometry · Computer Science 2020-09-29 Arijit Bishnu , Arijit Ghosh , Rogers Mathew , Gopinath Mishra , Subhabrata Paul

In this paper, we study grid-obstacle representations of graphs where we assign grid-points to vertices and define obstacles such that an edge exists if and only if an $xy$-monotone grid path connects the two endpoints without hitting an…

Computational Geometry · Computer Science 2017-08-31 Therese Biedl , Saeed Mehrabi

A point visibility graph is a graph induced by a set of points in the plane where the vertices of the graph represent the points in the point set and two vertices are adjacent if and only if no other point from the point set lies on the…

Discrete Mathematics · Computer Science 2018-05-17 Anne-Sophie Himmel , Clemens Hoffmann , Pascal Kunz , Vincent Froese , Manuel Sorge

An \emph{outer-string representation} of a graph $G$ is an intersection representation of $G$ where vertices are represented by curves (strings) inside the unit disk and each curve has exactly one endpoint on the boundary of the unit disk…

Combinatorics · Mathematics 2026-05-18 Todor Antić , Vít Jelínek , Jan Kratochvíl , Peter Stumpf

Given a graph $G(V,E)$, a vertex subset $S$ of $G$ is called an open packing in $G$ if no pair of distinct vertices in $S$ have a common neighbour in $G$. The size of a largest open packing in $G$ is called the open packing number,…

Discrete Mathematics · Computer Science 2024-07-15 M. A. Shalu , V. K. Kirubakaran

We introduce the class of interval $H$-graphs, which is the generalization of interval graphs, particularly interval bigraphs. For a fixed graph $H$ with vertices $a_1,a_2,\dots,a_k$, we say that an input graph $G$ with given partition…

Discrete Mathematics · Computer Science 2025-03-04 Haiko Müller , Arash Rafiey

A drawing of a graph is said to be a {\em straight-line drawing} if the vertices of $G$ are represented by distinct points in the plane and every edge is represented by a straight-line segment connecting the corresponding pair of vertices…

Combinatorics · Mathematics 2012-03-08 V S Padmini Mukkamala

Planar graphs can be represented as intersection graphs of different types of geometric objects in the plane, e.g., circles (Koebe, 1936), line segments (Chalopin \& Gon{\c{c}}alves, 2009), \textsc{L}-shapes (Gon{\c{c}}alves et al, 2018).…

Computational Geometry · Computer Science 2021-06-03 Dibyayan Chakraborty , Kshitij Gajjar

An ortho-polygon visibility representation of an $n$-vertex embedded graph $G$ (OPVR of $G$) is an embedding-preserving drawing of $G$ that maps every vertex to a distinct orthogonal polygon and each edge to a vertical or horizontal…

Computational Geometry · Computer Science 2017-05-17 Emilio Di Giacomo , Walter Didimo , William S. Evans , Giuseppe Liotta , Henk Meijer , Fabrizio Montecchiani , Stephen K. Wismath

Visibility graph of a polygon corresponds to its internal diagonals and boundary edges. For each vertex on the boundary of the polygon, we have a vertex in this graph and if two vertices of the polygon see each other there is an edge…

Computational Geometry · Computer Science 2024-02-22 Hossein Boomari , Mojtaba Ostovari , Alireza Zarei
‹ Prev 1 2 3 10 Next ›