Intersecting Red and Blue Line Segments in Optimal Time and Precision
نویسندگان
چکیده
A common geometric problem in computer graphics and geographic information systems is to compute the arrangement of a set of n segments that can be colored red and blue so that there are no red/red or blue/blue crossings. We give a sweep algorithm that uses the minimum arithmetic precision and runs in optimal O(n logn + k) time and O(n) space to output an arrangement with k vertices, or O(n log n) time to determine k. Our initial implementation in Java can be found at http:\\www.cs.unc.edu\~snoeyink\demos\rbseg.
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تاریخ انتشار 2000