Computing intersections in a set of line segments: the Bentley-Ottmann algorithm
نویسنده
چکیده
In these notes, we introduce a powerful technique for solving geometric problems. This technique, called the plane sweep technique, appears in Shamos’ Ph.D. thesis from 1978—which is considered the birthplace of computational geometry—although the concept was known already to geometers. The plane sweep technique gives efficient and reasonably simple algorithms for a large variety of geometric problems. In many cases, the only data structures needed are balanced binary search trees.
منابع مشابه
Exact , Efficient , and Complete Arrangement Computation for Cubic Curves 1
The Bentley-Ottmann sweep-line method can compute the arrangement of planar curves, provided a number of geometric primitives operating on the curves are available. We discuss the reduction of the primitives to the analysis of curves and curve pairs, and describe efficient realizations of these analyses for planar algebraic curves of degree three or less. We obtain a complete, exact, and effici...
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