On bends and distances of paths among obstacles in two-layer interconnection model

Abstract

We consider problems of finding assorted rectilinear paths among rectilinear obstacles in a two-layer interconnection model according to the number of bends and the 1-layer distance (y-distance). Using a horizontal wave-front approach, optimal /spl theta/(e log e) time algorithms are presented to find the shortest path and the minimum-bend path using linear space, and to find the shortest minimum-bend path and the minimum-bend shortest path using O(e log e) space, where e is the number of obstacle edges. By the same approach, we also derive an algorithm for finding a shortest two-layer distance (xy-distance) minimum-bend path in optimal /spl theta/(e log e) time using O(e log e) space. >