Weak Visibility Queries of Line Segments in Simple Polygons
نویسندگان
چکیده
Given a simple polygon P in the plane, we present new algorithms and data structures for computing the weak visibility polygon from any query line segment in P . We build a data structure in O(n) time and O(n) space that can compute the visibility polygon for any query line segment s in O(k log n) time, where k is the size of the visibility polygon of s and n is the number of vertices of P . Alternatively, we build a data structure in O(n) time and O(n) space that can compute the visibility polygon for any query line segment in O(k + log n) time.
منابع مشابه
Weak visibility queries of line segments in simple polygons and polygonal domains
In this paper we consider the problem of computing the weak visibility polygon of any query line segment pq (or WVP(pq)) inside a given polygon P . Our first non-trivial algorithm runs in simple polygons and needs O(n log n) time and O(n) space in the preprocessing phase to report WVP(pq) of any query line segment pq in time O(log n + |WVP(pq)|). We also give an algorithm to compute the weak vi...
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