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arXiv · 0806.1416

Highway Hull Revisited

Greg Aloupis·Jean Cardinal·Sebastien Collette·Ferran Hurtado·Stefan Langerman·Joseph O'Rourke·Belen Palop
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Abstract

A highway H is a line in the plane on which one can travel at a greater speed than in the remaining plane. One can choose to enter and exit H at any point. The highway time distance between a pair of points is the minimum time required to move from one point to the other, with optional use of H. The highway hull HH(S,H) of a point set S is the minimal set containing S as well as the shortest paths between all pairs of points in HH(S,H), using the highway time distance. We provide a Theta(n log n) worst-case time algorithm to find the highway hull under the L_1 metric, as well as an O(n log^2 n) time algorithm for the L_2 metric which improves the best known result of O(n^2). We also define and construct the useful region of the plane: the region that a highway must intersect in order that the shortest path between at least one pair of points uses the highway.

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Greg Aloupis, Jean Cardinal, Sebastien Collette, Ferran Hurtado, Stefan Langerman, Joseph O'Rourke, Belen Palop. 2009-04-22. Highway Hull Revisited. https://arxiv.org/abs/0806.1416

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