Vertexlights with Fixed Directions in Simple Polygons
نویسنده
چکیده
We study the problem of determining the smallest α ∈ [0, 2π] for a given simple polygon P with n vertices, such that P can be illuminated by α-vertexlights the directions of which are fixed. We present an algorithm that finds a solution to this problem in O(rn) time, where r is the number of reflex vertices of P . Furthermore we show that with the help of parametric search the problem can be solved in O(rn log n) time. We use the extended real RAM as the model of computation.
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