Efficient algorithms for generalized intersection searching on non-iso-oriented objects

Generalized intersection searching problems are a class of geometric query-retrieval problems where the questions of interest concern the intersection of a query object with aggregates of geometric objects (rather than with individual objects.) This class contains, as a special case, the well-studied class of standard intersection searching problems and is rich in applications. Unfortunately, the solutions known for the standard problems do not yield efficient solutions to the generalized problems. Recently, efficient solutions have been given for generalized problems where the input and query objects are iso-oriented (i.e., axes-parallel) or where the aggregated satisfy additional properties (e.g., connectedness). In this paper, efficient algorithms are given for several generalized problems involving non-iso-oriented objects. These problems include: generalized halfspace range searching, segment intersection searching, triangle stabbing, and triangle range searching. The techniques used include: computing suitable sparse representations of the input, persistent data structures, and filtering search.