# Computing the shortest path tree in a weak visibility polygon

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## Abstract

In this paper we propose two linear time algorithms for computing the shortest path tree rooted at any vertex of a weak visibility polygon. The first algorithm computes the shortest path tree in a polygon weakly visible from a *given internal segment*. The second algorithm computes the shortest path tree in a weak visibility polygon *without the knowledge* of a visibility segment. In both algorithms we use the convexity property of shortest paths in weak visibility polygons established in [4,11].

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## References

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© Springer-Verlag Berlin Heidelberg 1991