An O(log log n) Time Algorithm to Compute the Kernel of a Polygon
نویسنده
چکیده
The kernel of a polygon P is the set of all points that see the interior of P . It can be computed as the intersection of the halfplanes that are to the left of the edges of P . We present an O(log log n) time CRCW-PRAM algorithm using n/log log n processors to compute a representation of the kernel of P that allows to answer point containment and line intersection queries efficiently. Our approach is based on computing a subsequence of the edges that are sorted by slope and contain the “relevant” edges for the kernel computation. CR Classification: F.2.2
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عنوان ژورنال:
- Nord. J. Comput.
دوره 1 شماره
صفحات -
تاریخ انتشار 1994