Decomposing the Complement of the Union of Cubes and Boxes in Three Dimensions

IF 0.6 3区 数学 Q4 COMPUTER SCIENCE, THEORY & METHODS
{"title":"Decomposing the Complement of the Union of Cubes and Boxes in Three Dimensions","authors":"","doi":"10.1007/s00454-024-00632-2","DOIUrl":null,"url":null,"abstract":"<h3>Abstract</h3> <p>Let <span> <span>\\(\\mathcal {C}\\)</span> </span> be a set of <em>n</em> axis-aligned cubes of arbitrary sizes in <span> <span>\\({\\mathbb R}^3\\)</span> </span> in general position. Let <span> <span>\\(\\mathcal {U}:=\\mathcal {U}(\\mathcal {C})\\)</span> </span> be their union, and let <span> <span>\\(\\kappa \\)</span> </span> be the number of vertices on <span> <span>\\(\\partial \\mathcal {U}\\)</span> </span>; <span> <span>\\(\\kappa \\)</span> </span> can vary between <em>O</em>(1) and <span> <span>\\(\\Theta (n^2)\\)</span> </span>. We present a partition of <span> <span>\\(\\mathop {\\textrm{cl}}({\\mathbb R}^3\\setminus \\mathcal {U})\\)</span> </span> into <span> <span>\\(O(\\kappa \\log ^4 n)\\)</span> </span> axis-aligned boxes with pairwise-disjoint interiors that can be computed in <span> <span>\\(O(n \\log ^2 n + \\kappa \\log ^6 n)\\)</span> </span> time if the faces of <span> <span>\\(\\partial \\mathcal {U}\\)</span> </span> are pre-computed. We also show that a partition of size <span> <span>\\(O(\\sigma \\log ^4 n + \\kappa \\log ^2 n)\\)</span> </span>, where <span> <span>\\(\\sigma \\)</span> </span> is the number of input cubes that appear on <span> <span>\\(\\partial \\mathcal {U}\\)</span> </span>, can be computed in <span> <span>\\(O(n \\log ^2 n + \\sigma \\log ^8 n + \\kappa \\log ^6 n)\\)</span> </span> time if the faces of <span> <span>\\(\\partial \\mathcal {U}\\)</span> </span> are pre-computed. The complexity and runtime bounds improve to <span> <span>\\(O(n\\log n)\\)</span> </span> if all cubes in <span> <span>\\(\\mathcal {C}\\)</span> </span> are congruent and the faces of <span> <span>\\(\\partial \\mathcal {U}\\)</span> </span> are pre-computed. Finally, we show that if <span> <span>\\(\\mathcal {C}\\)</span> </span> is a set of arbitrary axis-aligned boxes in <span> <span>\\({\\mathbb R}^3\\)</span> </span>, then a partition of <span> <span>\\(\\mathop {\\textrm{cl}}({\\mathbb R}^3\\setminus \\mathcal {U})\\)</span> </span> into <span> <span>\\(O(n^{3/2}+\\kappa )\\)</span> </span> boxes can be computed in time <span> <span>\\(O((n^{3/2}+\\kappa )\\log n)\\)</span> </span>, where <span> <span>\\(\\kappa \\)</span> </span> is, as above, the number of vertices in <span> <span>\\(\\mathcal {U}(\\mathcal {C})\\)</span> </span>, which now can vary between <em>O</em>(1) and <span> <span>\\(\\Theta (n^3)\\)</span> </span>.</p>","PeriodicalId":50574,"journal":{"name":"Discrete & Computational Geometry","volume":"175 1","pages":""},"PeriodicalIF":0.6000,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Discrete & Computational Geometry","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00454-024-00632-2","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"COMPUTER SCIENCE, THEORY & METHODS","Score":null,"Total":0}
引用次数: 0

Abstract

Let \(\mathcal {C}\) be a set of n axis-aligned cubes of arbitrary sizes in \({\mathbb R}^3\) in general position. Let \(\mathcal {U}:=\mathcal {U}(\mathcal {C})\) be their union, and let \(\kappa \) be the number of vertices on \(\partial \mathcal {U}\) ; \(\kappa \) can vary between O(1) and \(\Theta (n^2)\) . We present a partition of \(\mathop {\textrm{cl}}({\mathbb R}^3\setminus \mathcal {U})\) into \(O(\kappa \log ^4 n)\) axis-aligned boxes with pairwise-disjoint interiors that can be computed in \(O(n \log ^2 n + \kappa \log ^6 n)\) time if the faces of \(\partial \mathcal {U}\) are pre-computed. We also show that a partition of size \(O(\sigma \log ^4 n + \kappa \log ^2 n)\) , where \(\sigma \) is the number of input cubes that appear on \(\partial \mathcal {U}\) , can be computed in \(O(n \log ^2 n + \sigma \log ^8 n + \kappa \log ^6 n)\) time if the faces of \(\partial \mathcal {U}\) are pre-computed. The complexity and runtime bounds improve to \(O(n\log n)\) if all cubes in \(\mathcal {C}\) are congruent and the faces of \(\partial \mathcal {U}\) are pre-computed. Finally, we show that if \(\mathcal {C}\) is a set of arbitrary axis-aligned boxes in \({\mathbb R}^3\) , then a partition of \(\mathop {\textrm{cl}}({\mathbb R}^3\setminus \mathcal {U})\) into \(O(n^{3/2}+\kappa )\) boxes can be computed in time \(O((n^{3/2}+\kappa )\log n)\) , where \(\kappa \) is, as above, the number of vertices in \(\mathcal {U}(\mathcal {C})\) , which now can vary between O(1) and \(\Theta (n^3)\) .

分解立方体和正方体的三维联合补集
Abstract Let \(\mathcal {C}\) be a set of n axis-aligned cubes of arbitrary sizes in \({\mathbb R}^3\) in general position.让(\mathcal {U}:=\mathcal {U}(\mathcal {C}))成为它们的联合,让(\kappa \)成为(\partial \mathcal {U})上的顶点数;(\kappa \)可以在O(1)和(\Theta (n^2))之间变化。我们将({mathop {textrm{cl}}({mathbb R}^3\setminus \mathcal {U}))划分为(O(\kappa \log ^4 n)\)个轴对齐的盒子,这些盒子的内部是成对的。如果预先计算好了(partial \mathcal {U})的面,那么就可以在(O(n \log ^2 n + \kappa \log ^6 n)时间内计算出这些面。我们还证明了一个大小为 \(O(\sigma \log ^4 n + \kappa \log ^2 n)\) 的分区。如果预先计算了 \(\partial \mathcal {U}\) 的面,那么可以在 \(O(n \log ^2 n + \sigma \log ^8 n + \kappa \log ^6 n)\)时间内计算出一个分区,其中 \(\sigma \)是出现在 \(\partial \mathcal {U}\) 上的输入立方体的数量。如果 \(\mathcal {C}\) 中的所有立方体都是全等的,并且 \(\partial \mathcal {U}\) 的面都是预先计算的,那么复杂度和运行时间的边界就会提高到 (O(n\log n)\)。最后,我们证明如果 \(\mathcal {C}\) 是 \({\mathbb R}^3\) 中任意轴对齐盒的集合 、那么可以在(O((n^{3/2}+\kappa )\log n)\)的时间内将\({textrm{cl}}({mathbb R}^3\setminus \mathcal {U}))分割成\(O(n^{3/2}+\kappa )\)个盒子。其中,\(\kappa\)和上面一样,是\(\mathcal {U}(\mathcal {C})\) 中顶点的数量,现在可以在O((n^{3/2}+\kappa)\log n)之间变化。现在可以在 O(1) 和 (Theta (n^3)\) 之间变化。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Discrete & Computational Geometry
Discrete & Computational Geometry 数学-计算机:理论方法
CiteScore
1.80
自引率
12.50%
发文量
99
审稿时长
6-12 weeks
期刊介绍: Discrete & Computational Geometry (DCG) is an international journal of mathematics and computer science, covering a broad range of topics in which geometry plays a fundamental role. It publishes papers on such topics as configurations and arrangements, spatial subdivision, packing, covering, and tiling, geometric complexity, polytopes, point location, geometric probability, geometric range searching, combinatorial and computational topology, probabilistic techniques in computational geometry, geometric graphs, geometry of numbers, and motion planning.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信