Article sans comité de lecture
Résumé : We study dynamic planar point location in the External Memory Model or Disk Access Model (DAM). Previous work in this model achieves polylog query and polylog amortized update time. We present a data structure with O(log2BN) query time and O(1B1−ϵlogBN) amortized update time, where N is the number of segments, B the block size and ϵ is a small positive constant, under the assumption that all faces have constant size. This is a B1−ϵ factor faster for updates than the fastest previous structure, and brings the cost of insertion and deletion down to subconstant amortized time for reasonable choices of N and B. Our structure solves the problem of vertical ray-shooting queries among a dynamic set of interior-disjoint line segments; this is well-known to solve dynamic planar point location for a connected subdivision of the plane with faces of constant size.