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200 papers

In the realm of computer-aided design (CAD) software, the intersection of B-spline surfaces stands as a fundamental operation. Despite the extensive history of surface intersection algorithms, the challenge of handling complex intersection…

Computational Geometry · Computer Science 2026-04-15 Chenming Gao , Hongwei Lin , Gengchen Li

We give several algorithms addressing computations of intersections of conjugate subgroups.

Group Theory · Mathematics 2018-11-13 Rita Gitik

Interpreting tangency as a limit of two transverse intersections, we obtain a concrete formula to enumerate smooth degree $d$ plane curves tangent to a given line at multiple points with arbitrary order of tangency. Extending that idea, we…

Algebraic Geometry · Mathematics 2025-02-25 Indranil Biswas , Apratim Choudhury , Ritwik Mukherjee , Anantadulal Paul

We determine the crossing number of polynomial size curve systems on standard surfaces, in terms of the genus, up to high precision.

Geometric Topology · Mathematics 2026-01-29 Sebastian Baader , Jasmin Jörg , Hugo Parlier

We obtain a coarse relationship between geometric intersection numbers of curves and the sum of their subsurface projection distances with explicit quasi-constants. By using this relationship, we give applications in the studies of the…

Geometric Topology · Mathematics 2017-09-12 Yohsuke Watanabe

Normal surface theory is a central tool in algorithmic three-dimensional topology, and the enumeration of vertex normal surfaces is the computational bottleneck in many important algorithms. However, it is not well understood how the number…

Geometric Topology · Mathematics 2010-06-18 Benjamin A. Burton

Street intersection counts and densities are ubiquitous measures in transport geography and planning. However, typical street network data and typical street network analysis tools can substantially overcount them. This article explains the…

Physics and Society · Physics 2025-05-01 Geoff Boeing

The need to compute the intersections between a line and a high-order curve or surface arises in a large number of finite element applications. Such intersection problems are easy to formulate but hard to solve robustly. We introduce a…

Numerical Analysis · Mathematics 2020-11-09 Xiao Xiao , Laurent Buse , Fehmi Cirak

Counting the number of triangles in a graph has many important applications in network analysis. Several frequently computed metrics like the clustering coefficient and the transitivity ratio need to count the number of triangles in the…

Data Structures and Algorithms · Computer Science 2013-04-24 Mostafa Haghir Chehreghani

Plotting solution sets for particular equations may be complicated by the existence of turning points. Here we describe an algorithm which not only overcomes such problematic points, but does so in the most general of settings. Applications…

Numerical Analysis · Mathematics 2011-07-05 Steven Pollack , Daniel Badali , Jonathan Pollack

Geometry processing presents a variety of difficult numerical problems, each seeming to require its own tailored solution. This breadth is largely due to the expansive list of geometric primitives, e.g., splines, triangles, and hexahedra,…

Computational Geometry · Computer Science 2021-10-19 Zoë Marschner , Paul Zhang , David Palmer , Justin Solomon

The generalized winding number is an essential part of the geometry processing toolkit, allowing to quantify how much a given point is inside a surface, even when the surface has boundaries and noise. We propose a new universal method to…

Graphics · Computer Science 2025-09-16 Cedric Martens , Mikhail Bessmeltsev

We present a practical algorithm to test whether a 3-manifold given by a triangulation or an ideal triangulation contains a closed essential surface. This property has important theoretical and algorithmic consequences. As a testament to…

Geometric Topology · Mathematics 2025-07-01 Benjamin A. Burton , Stephan Tillmann

Line intersection with convex and un-convex polygons or polyhedron algorithms are well known as line clipping algorithms and very often used in computer graphics. Rendering of geometrical problems often leads to ray tracing techniques, when…

Graphics · Computer Science 2022-08-10 Vaclav Skala

Counting triangles in a graph and incident to each vertex is a fundamental and frequently considered task of graph analysis. We consider how to efficiently do this for huge graphs using massively parallel distributed-memory machines.…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-07-24 Peter Sanders , Tim Niklas Uhl

We describe an efficient algorithm to compute a pseudotriangulation of a finite planar family of pairwise disjoint convex bodies presented by its chirotope. The design of the algorithm relies on a deepening of the theory of visibility…

Computational Geometry · Computer Science 2012-08-14 Luc Habert , Michel Pocchiola

We present efficient algorithms for detecting central and mirror symmetry for the case of algebraic curves defined by means of polynomial parametrizations. The algorithms are based on the existence of a linear relationship between two…

Algebraic Geometry · Mathematics 2012-12-27 Juan G. Alcazar

The concept of a normal surface in a triangulated, compact 3-manifold was generalised by Thurston to a spun-normal surface in a non-compact 3-manifold with ideal triangulation. This paper defines a boundary curve map which takes a…

Geometric Topology · Mathematics 2007-06-12 Stephan Tillmann

Given two curves in $\PP^3$, either implicitly or by a parameterization, we want to check if they intersect. For that purpose, we present and further develop generalized resultant techniques. Our aim is to provide a closed formula in the…

Algebraic Geometry · Mathematics 2007-05-23 Laurent Buse , Andre Galligo

Intersection algorithms are very important in computation of geometrical problems. Algorithms for a line intersection with linear or quadratic surfaces are quite efficient. However, algorithms for a line intersection with other surfaces are…

Graphics · Computer Science 2023-01-10 Vaclav Skala