title: On encoding boundaries with quadtrees.
abstract: The ``line quadtree'' data structure hierarchically represents a region and its boundary. Based on the standard quadtree, each node in this structure stores adjacency information as well. While line quadtrees use the same amount of space as standard qaudtrees, they facilitate several region processing algorithms. In particular, we describe efficient algorithms for boundary and superimposing two maps encoded as line quadtrees.
authors.affiliation: Department of Computer Science and the Center for Automation Research, University of Maryland, College Park, MD 20742.
authors.forename: H
authors.initials: H
authors.lastname: Samet
authors.forename: R E
authors.initials: RE
authors.lastname: Webber