A Simple Dynamization of Trapezoidal Point Location in Planar Subdivisions

Milutin Brankovic, Nikola Grujic, André van Renssen, Martin P. Seybold, Emanuela Merelli, Artur Czumaj, Anuj Dawar
2020 International Colloquium on Automata, Languages and Programming  
We study how to dynamize the Trapezoidal Search Tree (TST) - a well known randomized point location structure for planar subdivisions of kinetic line segments. Our approach naturally extends incremental leaf-level insertions to recursive methods and allows adaptation for the online setting. The dynamization carries over to the Trapezoidal Search DAG (TSD), which has linear size and logarithmic point location costs with high probability. On a set S of non-crossing segments, each TST update
more » ... ms expected 𝒪(log²|S|) operations and each TSD update performs expected 𝒪(log |S|) operations. We demonstrate the practicality of our method with an open-source implementation, based on the Computational Geometry Algorithms Library, and experiments on the update performance.
doi:10.4230/lipics.icalp.2020.18 dblp:conf/icalp/BrankovicGRS20 fatcat:woagkpcu5vfxzmgifanvk5sgqa