English

The dilation of the Delaunay triangulation is greater than {\pi}/2

Computational Geometry 2010-06-03 v1

Abstract

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 the length of the shortest path from p to p' in T over the Euclidean distance ||pp'||, can be at most {\pi}/2 \approx 1.5708. In this paper, we show how to construct point sets in convex position with dilation > 1.5810 and in general position with dilation > 1.5846. Furthermore, we show that a sufficiently large set of points drawn independently from any distribution will in the limit approach the worst-case dilation for that distribution.

Keywords

Cite

@article{arxiv.1006.0291,
  title  = {The dilation of the Delaunay triangulation is greater than {\pi}/2},
  author = {Prosenjit Bose and Luc Devroye and Maarten Löffler and Jack Snoeyink and Vishal Verma},
  journal= {arXiv preprint arXiv:1006.0291},
  year   = {2010}
}

Comments

12 pages, 6 figures, invited to the special edition of Computational Geometry Theory and Applications for papers from CCCG 2009