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Related papers: The Straight-Line RAC Drawing Problem is NP-Hard

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A rectangle visibility representation (RVR) of a graph consists of an assignment of axis-aligned rectangles to vertices such that for every edge there exists a horizontal or vertical line of sight between the rectangles assigned to its…

Computational Geometry · Computer Science 2019-09-04 Therese Biedl , Giuseppe Liotta , Fabrizio Montecchiani

Circular layouts are a popular graph drawing style, where vertices are placed on a circle and edges are drawn as straight chords. Crossing minimization in circular layouts is \NP-hard. One way to allow for fewer crossings in practice are…

Computational Geometry · Computer Science 2018-03-16 Fabian Klute , Martin Nöllenburg

The crossing angle of a straight-line drawing $\Gamma$ of a graph $G=(V, E)$ is the smallest angle between two crossing edges in $\Gamma$. Deciding whether a graph $G$ has a straight-line drawing with a crossing angle of $90^\circ$ is…

Computational Geometry · Computer Science 2018-08-01 Almut Demel , Dominik Dürrschnabel , Tamara Mchedlidze , Marcel Radermacher , Lasse Wulf

We prove that the following problem is complete for the existential theory of the reals: Given a planar graph and a polygonal region, with some vertices of the graph assigned to points on the boundary of the region, place the remaining…

Computational Complexity · Computer Science 2018-09-07 Anna Lubiw , Tillmann Miltzow , Debajyoti Mondal

In a Lombardi drawing of a graph the vertices are drawn as points and the edges are drawn as circular arcs connecting their respective endpoints. Additionally, all vertices have perfect angular resolution, i.e., all angles incident to a…

Computational Geometry · Computer Science 2023-08-14 Paul Jungeblut

A drawing of a graph in the plane is {\it pseudolinear} if the edges of the drawing can be extended to doubly-infinite curves that form an arrangement of pseudolines, that is, any pair of edges crosses precisely once. A special case are…

In this paper, we introduce and study "geometric simultaneous RAC drawing problems", i.e., a combination of problems on geometric RAC drawings and geometric simultaneous graph drawings. To the best of our knowledge, this is the first time…

Data Structures and Algorithms · Computer Science 2011-06-15 Evmorfia N. Argyriou , Michael A. Bekos , Michael Kaufmann , Antonios Symvonis

A graph is 1-planar if it can be drawn in the plane so that each edge is crossed at most once. However, there are 1-planar graphs which do not admit a straight-line 1-planar drawing. We show that every 1-planar graph has a straight-line…

Computational Geometry · Computer Science 2021-09-07 Franz J. Brandenburg

NP-complete problems should be hard on some instances but those may be extremely rare. On generic instances many such problems, especially related to random graphs, have been proven easy. We show the intractability of random instances of a…

Computational Complexity · Computer Science 2018-10-25 Leonid A. Levin , Ramarathnam Venkatesan

We explore what could make recognition of particular intersection-defined classes hard. We focus mainly on unit grid intersection graphs (UGIGs), i.e., intersection graphs of unit-length axis-aligned segments and grid intersection graphs…

Computational Geometry · Computer Science 2022-01-24 Irina Mustata , Martin Pergel

Properties of graphs that can be characterized by the spectrum of the adjacency matrix of the graph have been studied systematically recently. Motivated by the complexity of these properties, we show that there are such properties for which…

Combinatorics · Mathematics 2020-01-28 Omid Etesami , Willem H. Haemers

The crossing resolution of a non-planar drawing of a graph is the value of the minimum angle formed by any pair of crossing edges. Recent experiments have shown that the larger the crossing resolution is, the easier it is to read and…

Data Structures and Algorithms · Computer Science 2018-09-03 Michael A. Bekos , Henry Förster , Christian Geckeler , Lukas Holländer , Michael Kaufmann , Amadäus M. Spallek , Jan Splett

We exactly settle the complexity of graph realization, graph rigidity, and graph global rigidity as applied to three types of graphs: "globally noncrossing" graphs, which avoid crossings in all of their configurations; matchstick graphs,…

Computational Geometry · Computer Science 2025-10-21 Zachary Abel , Erik D. Demaine , Martin L. Demaine , Sarah Eisenstat , Jayson Lynch , Tao B. Schardl

Computing a minimum-area planar straight-line drawing of a graph is known to be NP-hard for planar graphs, even when restricted to outerplanar graphs. However, the complexity question is open for trees. Only a few hardness results are known…

Computational Geometry · Computer Science 2017-09-01 Therese Biedl , Debajyoti Mondal

We study a question that lies at the intersection of classical research subjects in Topological Graph Theory and Graph Drawing: Computing a drawing of a graph with a prescribed number of crossings on a given set $S$ of points, while…

Computational Geometry · Computer Science 2025-08-27 Giuseppe Di Battista , Giuseppe Liotta , Maurizio Patrignani , Antonios Symvonis , Ioannis G. Tollis

We investigate the problem of constructing planar drawings with few bends for two related problems, the partially embedded graph problem---to extend a straight-line planar drawing of a subgraph to a planar drawing of the whole graph---and…

Computational Geometry · Computer Science 2014-10-31 Timothy M. Chan , Fabrizio Frati , Carsten Gutwenger , Anna Lubiw , Petra Mutzel , Marcus Schaefer

NAC-colourings of graphs correspond to flexible quasi-injective realisations in $\mathbb {R} ^2$. A special class of NAC-colourings are those that arise from stable cuts. We give sharp thresholds for the random graph to have no stable cut…

Combinatorics · Mathematics 2025-10-08 Katie Clinch , John Haslegrave , Tony Huynh , Anthony Nixon

Unit edge-length drawings, rectilinear drawings (where each edge is either a horizontal or a vertical segment), and rectangular face drawings are among the most studied subjects in Graph Drawing. However, most of the literature on these…

In this paper, we study arrangements of orthogonal circles, that is, arrangements of circles where every pair of circles must either be disjoint or intersect at a right angle. Using geometric arguments, we show that such arrangements have…

Computational Geometry · Computer Science 2019-08-27 Steven Chaplick , Henry Förster , Myroslav Kryven , Alexander Wolff

In a drawing of a clustered graph vertices and edges are drawn as points and curves, respectively, while clusters are represented by simple closed regions. A drawing of a clustered graph is c-planar if it has no edge-edge, edge-region, or…

Discrete Mathematics · Computer Science 2014-02-19 Patrizio Angelini , Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati , Maurizio Patrignani , Vincenzo Roselli