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arXiv · 1009.2521

An Improved Algorithm for Reconstructing a Simple Polygon from the Visibility Angles

Danny Z. Chen·Haitao Wang
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Abstract

In this paper, we study the following problem of reconstructing a simple polygon: Given a cyclically ordered vertex sequence of an unknown simple polygon P of n vertices and, for each vertex v of P, the sequence of angles defined by all the visible vertices of v in P, reconstruct the polygon P (up to similarity). An O(n^3 log n) time algorithm has been proposed for this problem. We present an improved algorithm with running time O(n^2), based on new observations on the geometric structures of the problem. Since the input size (i.e., the total number of input visibility angles) is O(n^2) in the worst case, our algorithm is worst-case optimal.

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Danny Z. Chen, Haitao Wang. 2010-09-13. An Improved Algorithm for Reconstructing a Simple Polygon from the Visibility Angles. https://arxiv.org/abs/1009.2521

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