@article{4104,
  abstract     = {Point location, often known in graphics as “hit detection,” is one of the fundamental problems of computational geometry. In a point location query we want to identify which of a given collection of geometric objects contains a particular point. Let $\mathcal{S}$ denote a subdivision of the Euclidean plane into monotone regions by a straight-line graph of $m$ edges. In this paper we exhibit a substantial refinement of the technique of Lee and Preparata [SIAM J. Comput., 6 (1977), pp. 594–606] for locating a point in $\mathcal{S}$ based on separating chains. The new data structure, called a layered dag, can be built in $O(m)$ time, uses $O(m)$ storage, and makes possible point location in $O(\log m)$ time. Unlike previous structures that attain these optimal bounds, the layered dag can be implemented in a simple and practical way, and is extensible to subdivisions with edges more general than straight-line segments.
© 1986 Society for Industrial and Applied Mathematics},
  author       = {Edelsbrunner, Herbert and Guibas, Leonidas and Stolfi, Jorge},
  issn         = {1095-7111},
  journal      = {SIAM Journal on Computing},
  number       = {2},
  pages        = {317 -- 340},
  publisher    = {SIAM},
  title        = {{Optimal point location in a monotone subdivision}},
  doi          = {10.1137/0215023},
  volume       = {15},
  year         = {1986},
}