Predicates for line transversals to lines and line segments in three-dimensional space

When an observer is in a 3D scene, a topological change in the view arises when the line of sight is tangent to four objects. If we consider polyhedral scenes, the relevant lines of sight are transversals to some edges of the polyhedra. In this paper we investigate predicates about visibility events arising in this context. Namely, we consider the predicates for counting the number of line transversals to lines and segments in 3D and the predicate for determining whether a line of sight is intersected by a triangle. We also consider a predicate that order these visibility events in the rotating plane-sweep algorithm of Br

• Type: Conference
• Year: 2008
• Where: COMPGEOM
• Authors: Olivier Devillers, Marc Glisse, Sylvain Lazard
• Keywords: COMPGEOM 2008, Discrete Geometry, Plücker Coordinates, Procedure, Visibility Events