,
Yakov Nekrich
,
Martin P. Seybold
Creative Commons Attribution 4.0 International license
In a set of planes in ℝ³, the k-lowest planes query asks for the k lowest planes pierced by a vertical line q. In this paper we describe a semi-dynamic insertion-only data structure that answers k-lowest planes queries in optimal O(log n+k) time. Our data structure uses O(n) space, where n is the number of stored planes, and supports insertions in O(log⁸ n) amortized time. This result provides the first query optimal data structures for several fundamental problems: - An insertion-only structure that answers 3D halfspace range reporting queries on a set of n points in O(log n+k) time, where k is the number of reported points. - An insertion-only structure that answers 3D vertical ray shooting queries on a set of n planes in O(log n+k) time, where k is the number of reported planes. - An insertion-only structure that answers planar k-nearest neighbor queries in O(log n + k) time for any prescribed k (specified at query time). - An insertion-only structure that answers planar circular range reporting queries in time O(log n + k), where k is the number of reported points. For all of the above problems the query bound O(log n + k) is optimal, even in the static scenario. All of the above structures use linear O(n) space and support insertions in O(log⁸ n) amortized time. We also obtain a query optimal static structure for a 4D problem. That is, one can compute in near-linear time a data structure that answers weighted halfspace range reporting queries in O(log n + k) time, where k is the number of reported points. The structure uses near-linear space.
@InProceedings{iacono_et_al:LIPIcs.ICALP.2026.113,
author = {Iacono, John and Nekrich, Yakov and Seybold, Martin P.},
title = {{Incremental k-Lowest Planes and Planar k-Nearest Neighbor with Optimal Query Time}},
booktitle = {53rd International Colloquium on Automata, Languages, and Programming (ICALP 2026)},
pages = {113:1--113:16},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-428-4},
ISSN = {1868-8969},
year = {2026},
volume = {374},
editor = {Bhattacharya, Sayan and Nanongkai, Danupon and Benedikt, Michael and Puppis, Gabriele},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ICALP.2026.113},
URN = {urn:nbn:de:0030-drops-265027},
doi = {10.4230/LIPIcs.ICALP.2026.113},
annote = {Keywords: Data Structures, Dynamic Data Structures, k Nearest-Neighbor Queries}
}