Optimal Binary Space Partitions in the Plane
نویسندگان
چکیده
An optimal bsp for a set S of disjoint line segments in the plane is a bsp for S that produces the minimum number of cuts. We study optimal bsps for three classes of bsps, which differ in the splitting lines that can be used when partitioning a set of fragments in the recursive partitioning process: free bsps can use any splitting line, restricted bsps can only use splitting lines through pairs of fragment endpoints, and auto-partitions can only use splitting lines containing a fragment. We obtain the two following results: – It is np-hard to decide whether a given set of segments admits an auto-partition that does not make any cuts. – An optimal restricted bsp makes at most 2 times as many cuts as an optimal free bsp for the same set of segments.
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