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Related papers: Computing a visibility polygon using few variables

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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 present two algorithms that compute the Newton polytope of a polynomial defining a hypersurface H in C^n using numerical computation. The first algorithm assumes that we may only compute values of f - this may occur if f is given as a…

Algebraic Geometry · Mathematics 2012-10-11 Jonathan D. Hauenstein , Frank Sottile

We present an algorithm that computes the girth of the intersection graph of $n$ given line segments in the plane in $O(n^{1.483})$ expected time. This is the first such algorithm with $O(n^{3/2-\varepsilon})$ running time for a positive…

Computational Geometry · Computer Science 2026-03-24 Timothy M. Chan , Yuancheng Yu

Mutual visibility in graphs provides a framework for analysing how vertices can observe one another along shortest paths free of internal obstructions. The visibility polynomial, which enumerates mutual-visibility sets of all orders, has…

Combinatorics · Mathematics 2026-04-10 Tonny K B , Shikhi M

While well-known methods to list the intersections of either a list of segments or a complex polygon aim at achieving optimal time-complexity they often do so at the cost of memory comsumption and complex code. Real-life software…

Computational Geometry · Computer Science 2013-05-28 Jean Souviron

Given a simple polygon $\mathscr{P}$, two points $x$ and $y$ within $\mathscr{P}$ are {\em visible} to each other if the line segment between $x$ and $y$ is contained in $\mathscr{P}$. The {\em visibility region} of a point $x$ includes all…

Computational Geometry · Computer Science 2025-11-14 Udvas Das , Binayak Dutta , Satyabrata Jana , Debabrata Pal , Sasanka Roy

Computing visibility on a geometric object requires heavy computations since it requires to identify pairs of points that are visible to each other, i.e. there is a straight segment joining them that stays in the close vicinity of the…

Computational Geometry · Computer Science 2026-03-13 Romain Negro , Jacques-Olivier Lachaud

The visibility algorithm has been recently introduced as a mapping between time series and complex networks. This procedure allows to apply methods of complex network theory for characterizing time series. In this work we present the…

Data Analysis, Statistics and Probability · Physics 2010-02-25 Bartolo Luque , Lucas Lacasa , Fernando Ballesteros , Jordi Luque

Real-time visibility determination in expansive or dynamically changing environments has long posed a significant challenge in computer graphics. Existing techniques are computationally expensive and often applied as a precomputation step…

Graphics · Computer Science 2025-09-30 Xiangyu Wang , Thomas Köhler , Jun Lin Qiu , Shohei Mori , Markus Steinberger , Dieter Schmalstieg

We describe a new algorithm to compute the geometric intersection number between two curves, given as edge vectors on an ideal triangulation. Most importantly, this algorithm runs in polynomial time in the bit-size of the two edge vectors.…

Geometric Topology · Mathematics 2016-05-12 Mark C. Bell , Richard C. H. Webb

We consider the following general scheduling problem: The input consists of n jobs, each with an arbitrary release time, size, and a monotone function specifying the cost incurred when the job is completed at a particular time. The…

Data Structures and Algorithms · Computer Science 2010-08-31 Nikhil Bansal , Kirk Pruhs

For two points in the closure of a simple polygon $P$, we say that they see each other in $P$ if the line segment uniting them does not intersect the exterior of $P$. The visibility graph of $P$ is the graph whose vertex set is the vertex…

Computational Geometry · Computer Science 2020-01-20 André C. Silva

Let G(V,E) be a simple graph and let X subset of V. Two vertices u and v are said to be X-visible if there exists a shortest u,v-path P such that V(P) intersection X is a subset of {u, v}. A set X is called a mutual-visibility set of G if…

Combinatorics · Mathematics 2026-04-10 Tonny K B , Shikhi M

Visibility graph reconstruction, which asks us to construct a polygon that has a given visibility graph, is a fundamental problem with unknown complexity (although visibility graph recognition is known to be in PSPACE). We show that two…

Data Structures and Algorithms · Computer Science 2017-09-04 Nodari Sitchinava , Darren Strash

We consider extending visibility polygon $(VP)$ of a given point $q$ $(VP(q))$, inside a simple polygon $\P$ by converting some edges of $\P$ to mirrors. We will show that several variations of the problem of finding mirror-edges to add at…

Computational Geometry · Computer Science 2017-08-04 Arash Vaezi , Bodhayan Roy , Mohammad Ghodsi , Anil Maheshwari

We show that the shadow vertex simplex algorithm can be used to solve linear programs in strongly polynomial time with respect to the number $n$ of variables, the number $m$ of constraints, and $1/\delta$, where $\delta$ is a parameter that…

Data Structures and Algorithms · Computer Science 2014-12-18 Tobias Brunsch , Anna Großwendt , Heiko Röglin

In memory-constrained algorithms we have read-only access to the input, and the number of additional variables is limited. In this paper we introduce the compressed stack technique, a method that allows to transform algorithms whose space…

Computational Geometry · Computer Science 2014-06-26 Luis Barba , Matias Korman , Stefan Langerman , Kunikiko Sadakane , Rodrigo Silveira

A subalgebraic approximation algorithm is proposed to estimate from a set of time series the parameters of the observer representation of a discrete-time polynomial system without inputs which can generate an approximation of the observed…

Optimization and Control · Mathematics 2015-07-09 Jana Němcová , Mihály Petreczky , Jan H. van Schuppen

Given a set of point sites in a simple polygon, the geodesic farthest-point Voronoi diagram partitions the polygon into cells, at most one cell per site, such that every point in a cell has the same farthest site with respect to the…

Computational Geometry · Computer Science 2018-02-20 Eunjin Oh , Luis Barba , Hee-Kap Ahn

The ability to capture rich representations of combinatorial structures has enabled the application of machine learning to tasks such as analysis and generation of floorplans, terrains, images, and animations. Recent work has primarily…

Computational Geometry · Computer Science 2025-10-23 Rahul Moorthy , Jun-Jee Chao , Volkan Isler