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arXiv · 1312.3711

Computing the $L_1$ Geodesic Diameter and Center of a Simple Polygon in Linear Time

Sang Won Bae·Matias Korman·Yoshio Okamoto·Haitao Wang
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Abstract

In this paper, we show that the $L_1$ geodesic diameter and center of a simple polygon can be computed in linear time. For the purpose, we focus on revealing basic geometric properties of the $L_1$ geodesic balls, that is, the metric balls with respect to the $L_1$ geodesic distance. More specifically, in this paper we show that any family of $L_1$ geodesic balls in any simple polygon has Helly number two, and the $L_1$ geodesic center consists of midpoints of shortest paths between diametral pairs. These properties are crucial for our linear-time algorithms, and do not hold for the Euclidean case.

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Sang Won Bae, Matias Korman, Yoshio Okamoto, Haitao Wang. 2013-12-13. Computing the $L_1$ Geodesic Diameter and Center of a Simple Polygon in Linear Time. https://arxiv.org/abs/1312.3711

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