VISIBILITY STABS AND DEPTH-FIRST SPIRALLING ON LINE SEGMENTS IN OUTPUT SENSITIVE TIME

Given a set S of n non-intersecting line segments in the plane, we vpresent a new technique for efficiently traversing the endpoint visibility graph of S to solve a variety of visibility problems in output sensitive time. In particular, we develop two techniques to compute the 2n visibility polygons of the endpoints of S, in output sensitive time. Depth-first spiralling is a technique that relies on the ordered endpoint visibility graph information to traverse the endpoints of S in a spiral-like manner using a combination of Jarvis' March and depth-first search. It is a practical method and has been implemented in C++ using LEDA.