The Delaunay triangulation of a planar point set is a fundamental construct in computational geometry. A simple algorithm to generate it is based on flips of diagonal edges in convex quads. We characterize the effect of a single edge flip in a triangulation on the geometric Laplacian of the triangulation, which leads to a simpler and shorter proof of a theorem of Rippa that the Dirichlet energy of any piecewise-linear scalar function on a triangulation obtains its minimum on the Delaunay triangulation. Using Rippa's theorem, we provide a spectral characterization of the Delaunay triangulation, namely that the spectrum of the geometric Laplacian is minimized on this triangulation. This spectral theorem then leads to a simpler proof of a theorem of Musin that the harmonic index also obtains its minimum on the Delaunay triangulation.
%0 Journal Article
%1 chen10
%A Chen, Renjie
%A Xu, Yin
%A Gotsman, Craig
%A Liu, Ligang
%D 2010
%J Computer Aided Geometric Design
%K delaunay dirichlet.energy spectral.graph.theory triangulation
%N 4
%P 295--300
%R 10.1016/j.cagd.2010.02.002
%T A Spectral Characterization of the Delaunay Triangulation
%V 27
%X The Delaunay triangulation of a planar point set is a fundamental construct in computational geometry. A simple algorithm to generate it is based on flips of diagonal edges in convex quads. We characterize the effect of a single edge flip in a triangulation on the geometric Laplacian of the triangulation, which leads to a simpler and shorter proof of a theorem of Rippa that the Dirichlet energy of any piecewise-linear scalar function on a triangulation obtains its minimum on the Delaunay triangulation. Using Rippa's theorem, we provide a spectral characterization of the Delaunay triangulation, namely that the spectrum of the geometric Laplacian is minimized on this triangulation. This spectral theorem then leads to a simpler proof of a theorem of Musin that the harmonic index also obtains its minimum on the Delaunay triangulation.
@article{chen10,
abstract = {The Delaunay triangulation of a planar point set is a fundamental construct in computational geometry. A simple algorithm to generate it is based on flips of diagonal edges in convex quads. We characterize the effect of a single edge flip in a triangulation on the geometric Laplacian of the triangulation, which leads to a simpler and shorter proof of a theorem of Rippa that the Dirichlet energy of any piecewise-linear scalar function on a triangulation obtains its minimum on the Delaunay triangulation. Using Rippa's theorem, we provide a spectral characterization of the Delaunay triangulation, namely that the spectrum of the geometric Laplacian is minimized on this triangulation. This spectral theorem then leads to a simpler proof of a theorem of Musin that the harmonic index also obtains its minimum on the Delaunay triangulation.},
added-at = {2012-12-28T19:10:59.000+0100},
author = {Chen, Renjie and Xu, Yin and Gotsman, Craig and Liu, Ligang},
biburl = {https://www.bibsonomy.org/bibtex/2564a778814dfbf93c23f7a458f3cbbe3/ytyoun},
doi = {10.1016/j.cagd.2010.02.002},
interhash = {7fbfdc4f6bcfc8e6b4f3e84a2749c044},
intrahash = {564a778814dfbf93c23f7a458f3cbbe3},
issn = {0167-8396},
journal = {Computer Aided Geometric Design},
keywords = {delaunay dirichlet.energy spectral.graph.theory triangulation},
number = 4,
pages = {295--300},
timestamp = {2016-11-16T07:50:01.000+0100},
title = {A Spectral Characterization of the {Delaunay} Triangulation},
volume = 27,
year = 2010
}