,
Valentin Polishchuk
Creative Commons Attribution 4.0 International license
We show how to preprocess a polygonal domain with holes so that the link distance (the number of links in a minimum-link path) between two query points in the domain can be reported efficiently. Using our data structures, the link diameter of the domain (i.e., the maximum number of links that may be required in a minimum-link path between two points in the domain) as well as the link center and radius of the domain (i.e., the point minimizing the maximum link distance to the furthest point in the domain and this maximum link distance) can be found in polynomial time. We also give a simpler algorithm for finding the link diameter, not using the link distance query structures. Answering 2-point link distance queries and computing the link diameter/radius/center in polygonal domains have been open questions since these problems were studied for simple polygons in the 90’s.
@InProceedings{hagedoorn_et_al:LIPIcs.WADS.2025.34,
author = {Hagedoorn, Mart and Polishchuk, Valentin},
title = {{Link Diameter, Radius and 2-Point Link Distance Queries in Polygonal Domains}},
booktitle = {19th International Symposium on Algorithms and Data Structures (WADS 2025)},
pages = {34:1--34:15},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-398-0},
ISSN = {1868-8969},
year = {2025},
volume = {349},
editor = {Morin, Pat and Oh, Eunjin},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.WADS.2025.34},
URN = {urn:nbn:de:0030-drops-242659},
doi = {10.4230/LIPIcs.WADS.2025.34},
annote = {Keywords: Minimum-link paths, link distance, diameter, center, radius, 2-point distance queries}
}