On approximating shortest paths in weighted triangular tessellations

We study the quality of weighted shortest paths when a continuous 2-dimensional space is discretized by a weighted triangular tessellation. In order to evaluate how well the tessellation approximates the 2-dimensional space, we study three types of shortest paths: aweighted shortest path SPw(s, t),...

Full description

Bibliographic Details
Authors: Bose, Prosenjit, Esteban Pascual, Guillermo|||0000-0002-0751-7729, Orden Martín, David|||0000-0001-5403-8467, Silveira Isoba, Rodrigo Ignacio
Format: article
Publication Date:2023
Country:España
Institution:Universidad de Alcalá (UAH)
Repository:e_Buah Biblioteca Digital Universidad de Alcalá
Language:English
OAI Identifier:oai:ebuah.uah.es:10017/64219
Online Access:http://hdl.handle.net/10017/64219
https://dx.doi.org/10.1016/j.artint.2023.103898
Access Level:Open access
Keyword:Shortest path
Any-angle path planning
Tessellation
Weighted region problem
Matemáticas
Mathematics
Description
Summary:We study the quality of weighted shortest paths when a continuous 2-dimensional space is discretized by a weighted triangular tessellation. In order to evaluate how well the tessellation approximates the 2-dimensional space, we study three types of shortest paths: aweighted shortest path SPw(s, t), which is a shortest path from s to t in the space; aweighted shortest vertex path SVPw(s, t), which is an any-angle shortest path; and a weighted shortest grid path SGPw(s, t), which is a shortest path whose edges are edges of the tessellation. Given any arbitrary weight assignment to the faces of a triangular tessellation, thus extending recent results by Bailey et al. (2021) [6], we prove upper and lower bounds on the ratios SGPw(s,t) SPw(s,t) , SVPw(s,t) SPw(s,t) , SGPw(s,t) SVPw(s,t) , which provide estimates on the quality of the approximation. It turns out, surprisingly, that our worst-case bounds are independent of any weight assignment. Our main result is that SGPw(s,t) √ SPw(s,t) = 2 3 ≈1.15 in the worst case, and this is tight. As a corollary, for the weighted any-angle path SVPw(s, t) we obtain the approximation result SVPw(s,t) SPw(s,t) ⪅ 1.15.