English
Related papers

Related papers: Straight Skeletons of Three-Dimensional Polyhedra

200 papers

We give an algorithm that reduces the straight skeleton to the motorcycle graph in $O(n\log n)$ time for simple polygons and $O(n(\log n)\log m)$ time for a planar straight line graph (PSLG) with $m$ connected components. This improves on…

Computational Geometry · Computer Science 2014-08-07 John C. Bowers

Two single parameter families of polyhedra $P(\psi)$ are constructed in three dimensional spaces of constant curvature $C(\psi)$. Identification of the faces of the polyhedra via isometries results in cone manifolds $M(\psi)$ which are…

Geometric Topology · Mathematics 2007-05-23 A Aalam

Object skeleton is a useful cue for object detection, complementary to the object contour, as it provides a structural representation to describe the relationship among object parts. While object skeleton extraction in natural images is a…

Computer Vision and Pattern Recognition · Computer Science 2016-04-07 Wei Shen , Kai Zhao , Yuan Jiang , Yan Wang , Zhijiang Zhang , Xiang Bai

Given vertex valencies admissible for a self-dual polyhedral graph, we describe an algorithm to explicitly construct such a polyhedron. Inputting in the algorithm permutations of the degree sequence can give rise to non-isomorphic graphs.…

Combinatorics · Mathematics 2021-08-03 Riccardo W. Maffucci

In pure integer linear programming it is often desirable to work with polyhedra that are full-dimensional, and it is well known that it is possible to reduce any polyhedron to a full-dimensional one in polynomial time. More precisely, using…

Optimization and Control · Mathematics 2024-02-06 Alberto Del Pia

In this paper, we have examined the problem of embedding a cycle of n vertices onto a given set of n points inside a simple polygon. The goal of the problem is that the cycle must be embedded without bends and does not intersect itself and…

Computational Geometry · Computer Science 2022-06-24 Maryam Fadavian , Heidar Fadavian

Indirect hex-dominant meshing methods rely on the detection of adjacent tetrahedra an algorithm that performs this identification and builds the set of all possible combinations of tetrahedral elements of an input mesh T into hexahedra,…

Computational Geometry · Computer Science 2018-01-08 Jeanne Pellerin , Amaury Johnen , Kilian Verhetsel , Jean-Francois Remacle

In this paper, we introduce a method for reconstructing 3D humans from a single image using a biomechanically accurate skeleton model. To achieve this, we train a transformer that takes an image as input and estimates the parameters of the…

Computer Vision and Pattern Recognition · Computer Science 2025-03-28 Yan Xia , Xiaowei Zhou , Etienne Vouga , Qixing Huang , Georgios Pavlakos

Writing an uncomplicated, robust, and scalable three-dimensional convex hull algorithm is challenging and problematic. This includes, coplanar and collinear issues, numerical accuracy, performance, and complexity trade-offs. While there are…

Computational Geometry · Computer Science 2023-04-11 Ben Kenwright

Answering a question posed by Joseph Malkevitch, we prove that there exists a polyhedral graph, with triangular faces, such that every realization of it as the graph of a convex polyhedron includes at least one face that is a scalene…

Computational Geometry · Computer Science 2021-07-02 David Eppstein

We consider polyhedral approximations of strictly convex compacta in finite dimensional Euclidean spaces (such compacta are also uniformly convex). We obtain the best possible estimates for errors of considered approximations in the…

Functional Analysis · Mathematics 2010-10-13 Maxim V. Balashov , Dušan Repovš

In this paper we develop a concrete way to construct bodies of constant width in dimension three. They are constructed from special embeddings of self-dual graphs.

Metric Geometry · Mathematics 2016-11-30 Luis Montejano , Edgardo Roldán-Pensado

A convex polyhedron is Rupert if a hole can be cut into it (making its genus $1$) such that an identical copy of the polyhedron can pass through the hole. Resolving a conjecture of Jerrard-Wetzel-Yuan, Steininger and Yurkevich recently…

Metric Geometry · Mathematics 2026-04-30 Tony Zeng

In this paper, an effective method with time complexity of $\mathcal{O}(K^{3/2}N^2\log \frac{K}{\epsilon_0})$ is introduced to find an approximation of the convex hull for $N$ points in dimension $n$, where $K$ is close to the number of…

Computational Geometry · Computer Science 2016-03-15 Hossein Sartipizadeh , Tyrone L. Vincent

An edge-unfolding of a polyhedron is produced by cutting along edges and flattening the faces to a *net*, a connected planar piece with no overlaps. A *grid unfolding* allows additional cuts along grid edges induced by coordinate planes…

Computational Geometry · Computer Science 2007-05-23 Mirela Damian , Robin Flatland , Joseph O'Rourke

Regular polygonal complexes in euclidean 3-space are discrete polyhedra-like structures with finite or infinite polygons as faces and with finite graphs as vertex-figures, such that their symmetry groups are transitive on the flags. The…

Combinatorics · Mathematics 2012-10-09 Daniel Pellicer , Egon Schulte

A closed quasigeodesic is a closed curve on the surface of a polyhedron with at most $180^\circ$ of surface on both sides at all points; such curves can be locally unfolded straight. In 1949, Pogorelov proved that every convex polyhedron…

Computational Geometry · Computer Science 2025-10-21 Erik D. Demaine , Adam C. Hesterberg , Jason S. Ku

We establish a bound of $O(n^2k^{1+\eps})$, for any $\eps>0$, on the combinatorial complexity of the set $\T$ of line transversals of a collection $\P$ of $k$ convex polyhedra in $\reals^3$ with a total of $n$ facets, and present a…

Computational Geometry · Computer Science 2008-07-09 Haim Kaplan , Natan Rubin , Micha Sharir

Kokotsakis studied the following problem in 1932: Given is a rigid closed polygonal line (planar or non-planar), which is surrounded by a polyhedral strip, where at each polygon vertex three faces meet. Determine the geometries of these…

Computational Geometry · Computer Science 2022-02-17 Georg Nawratil

We introduce a notion of $k$-convexity and explore polygons in the plane that have this property. Polygons which are \mbox{$k$-convex} can be triangulated with fast yet simple algorithms. However, recognizing them in general is a 3SUM-hard…

Computational Geometry · Computer Science 2010-07-22 Oswin Aichholzer , Franz Aurenhammer , Erik D. Demaine , Ferran Hurtado , Pedro Ramos , Jorge Urrutia