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Related papers: Computing the flip distance between triangulations

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Delaunay flip is an elegant, simple tool to convert a triangulation of a point set to its Delaunay triangulation. The technique has been researched extensively for full dimensional triangulations of point sets. However, an important case of…

Computational Geometry · Computer Science 2007-12-13 Siu-Wing Cheng , Tamal K. Dey

We study the problem of computing the Fr\'echet distance between two polygonal curves under transformations. First, we consider translations in the Euclidean plane. Given two curves $\pi$ and $\sigma$ of total complexity $n$ and a threshold…

Computational Geometry · Computer Science 2025-01-23 Kevin Buchin , Maike Buchin , Zijin Huang , André Nusser , Sampson Wong

Given two pants decompositions of a compact orientable surface $S$, we give an upper bound for their distance in the pants graph that depends logarithmically on their intersection number and polynomially on the Euler characteristic of $S$.…

Geometric Topology · Mathematics 2025-11-06 Marc Lackenby , Mehdi Yazdi

We consider the problem of counting straight-edge triangulations of a given set $P$ of $n$ points in the plane. Until very recently it was not known whether the exact number of triangulations of $P$ can be computed asymptotically faster…

Computational Geometry · Computer Science 2014-04-02 Victor Alvarez , Karl Bringmann , Saurabh Ray , Raimund Seidel

We give a new algorithm to simplify a given triangulation with respect to a given curve. The simplification uses flips together with powers of Dehn twists in order to complete in polynomial time in the bit-size of the curve.

Geometric Topology · Mathematics 2016-04-25 Mark C. Bell

A suitable measure for the similarity of shapes represented by parameterized curves or surfaces is the Fr\'echet distance. Whereas efficient algorithms are known for computing the Fr\'echet distance of polygonal curves, the same problem for…

Computational Geometry · Computer Science 2007-05-23 Helmut Alt , Maike Buchin

We report on the implementation of an algorithm for computing the set of all regular triangulations of finitely many points in Euclidean space. This algorithm, which we call down-flip reverse search, can be restricted, e.g., to computing…

Combinatorics · Mathematics 2018-10-30 Charles Jordan , Michael Joswig , Lars Kastner

Consider a plane graph G, drawn with straight lines. For every pair a,b of vertices of G, we compare the shortest-path distance between a and b in G (with Euclidean edge lengths) to their actual distance in the plane. The worst-case ratio…

Computational Geometry · Computer Science 2007-05-23 Rolf Klein , Martin Kutz

Consider the Delaunay triangulation T of a set P of points in the plane as a Euclidean graph, in which the weight of every edge is its length. It has long been conjectured that the dilation in T of any pair p, p \in P, which is the ratio of…

Computational Geometry · Computer Science 2010-06-03 Prosenjit Bose , Luc Devroye , Maarten Löffler , Jack Snoeyink , Vishal Verma

Given two points in the plane, a set of obstacles defined by closed curves, and an integer $k$, does there exist a path between the two designated points intersecting at most $k$ of the obstacles? This is a fundamental and well-studied…

Data Structures and Algorithms · Computer Science 2020-02-05 Eduard Eiben , Daniel Lokshtanov

Let $S$ be a planar point set in general position, and let $\mathcal{P}(S)$ be the set of all plane straight-line paths with vertex set $S$. A flip on a path $P \in \mathcal{P}(S)$ is the operation of replacing an edge $e$ of $P$ with…

Computational Geometry · Computer Science 2022-09-29 Oswin Aichholzer , Kristin Knorr , Wolfgang Mulzer , Johannes Obenaus , Rosna Paul , Birgit Vogtenhuber

We study the problem of computing the minimum area triangle that circumscribes a given $n$-sided convex polygon touching edge-to-edge. In other words, we compute the minimum area triangle that is the intersection of 3 half-planes out of $n$…

Computational Geometry · Computer Science 2022-08-15 Kai Jin , Zhiyi Huang

Let $P$ and $Q$ be simple polygons with $n$ vertices each. We wish to compute triangulations of $P$ and $Q$ that are combinatorially equivalent, if they exist. We consider two versions of the problem: if a triangulation of $P$ is given, we…

Computational Geometry · Computer Science 2026-03-03 Peyman Afshani , Boris Aronov , Kevin Buchin , Maike Buchin , Otfried Cheong , Katharina Klost , Carolin Rehs , Günter Rote

Let $\mathcal{P}$ be a set of $n=2m+1$ points in the plane in general position. We define the graph $GM_\mathcal{P}$ whose vertex set is the set of all plane matchings on $\mathcal{P}$ with exactly $m$ edges. Two vertices in…

Computational Geometry · Computer Science 2024-10-10 Oswin Aichholzer , Anna Brötzner , Daniel Perz , Patrick Schnider

We discuss the problem to count, or, more modestly, to estimate the number f(m,n) of unimodular triangulations of the planar grid of size $m\times n$. Among other tools, we employ recursions that allow one to compute the (huge) number of…

Combinatorics · Mathematics 2007-05-23 Volker Kaibel , Günter M. Ziegler

We associate to triangulations of infinite type surface a type of flip graph where simultaneous flips are allowed. Our main focus is on understanding exactly when two triangulations can be related by a sequence of flips. A consequence of…

Geometric Topology · Mathematics 2020-11-05 Ariadna Fossas , Hugo Parlier

We consider geometric triangulations of surfaces, i.e., triangulations whose edges can be realized by disjoint locally geodesic segments. We prove that the flip graph of geometric triangulations with fixed vertices of a flat torus or a…

Computational Geometry · Computer Science 2019-12-11 Vincent Despré , Jean-Marc Schlenker , Monique Teillaud

We define and investigate the Fr\'{e}chet edit distance problem. Given two polygonal curves $\pi$ and $\sigma$ and a threshhold value $\delta>0$, we seek the minimum number of edits to $\sigma$ such that the Fr\'{e}chet distance between the…

Computational Geometry · Computer Science 2024-03-20 Emily Fox , Amir Nayyeri , Jonathan James Perry , Benjamin Raichel

We provide a spectrum of new theoretical insights and practical results for finding a Minimum Dilation Triangulation (MDT), a natural geometric optimization problem of considerable previous attention: Given a set $P$ of $n$ points in the…

Computational Geometry · Computer Science 2025-02-26 Sándor P. Fekete , Phillip Keldenich , Michael Perk

Let $P$ be a set of $n$ points in the plane. A crossing-free structure on $P$ is a plane graph with vertex set $P$. Examples of crossing-free structures include triangulations of $P$, spanning cycles of $P$, also known as polygonalizations…

Computational Geometry · Computer Science 2013-12-18 Victor Alvarez , Karl Bringmann , Radu Curticapean , Saurabh Ray