{"title":"$\\mathbb{R}^3$中光滑曲线的近线性时间中轴逼近","authors":"Christian Scheffer","doi":"10.20382/jocg.v7i1a17","DOIUrl":null,"url":null,"abstract":"We present the first algorithm to approximate the medial axis $M_{\\gamma}$ of a smooth, closed curve $\\gamma \\subset \\mathbb{R}^3$ in near-linear time. Our algorithm works on a sufficiently dense \\eps-sample and comes with a convergence guarantee for the non-discrete, but continuous approximation object. As our approach also works correctly for a set of curves, we discuss the following application of the medial axis: The medial axis of two curves $\\gamma_1$ and $\\gamma_2$ can be applied to compute piecewise-linear simplifications of $\\gamma_1$ and $\\gamma_2$. In particular, a controllable tradeoff between the degree of simplification and the degree of falsification of the summed Fr\\'{e}chet distance between $\\gamma_1$ and $\\gamma_2$ is obtained. Finally, we show that for simplifying $\\gamma_1$ and $\\gamma_2$, our approximation, instead of $M_{\\gamma}$, can be applied while guaranteeing the same result.","PeriodicalId":54969,"journal":{"name":"International Journal of Computational Geometry & Applications","volume":"81 4 1","pages":"360-429"},"PeriodicalIF":0.0000,"publicationDate":"2016-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Near-linear time medial axis approximation of smooth curves in $\\\\mathbb{R}^3$\",\"authors\":\"Christian Scheffer\",\"doi\":\"10.20382/jocg.v7i1a17\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We present the first algorithm to approximate the medial axis $M_{\\\\gamma}$ of a smooth, closed curve $\\\\gamma \\\\subset \\\\mathbb{R}^3$ in near-linear time. Our algorithm works on a sufficiently dense \\\\eps-sample and comes with a convergence guarantee for the non-discrete, but continuous approximation object. As our approach also works correctly for a set of curves, we discuss the following application of the medial axis: The medial axis of two curves $\\\\gamma_1$ and $\\\\gamma_2$ can be applied to compute piecewise-linear simplifications of $\\\\gamma_1$ and $\\\\gamma_2$. In particular, a controllable tradeoff between the degree of simplification and the degree of falsification of the summed Fr\\\\'{e}chet distance between $\\\\gamma_1$ and $\\\\gamma_2$ is obtained. Finally, we show that for simplifying $\\\\gamma_1$ and $\\\\gamma_2$, our approximation, instead of $M_{\\\\gamma}$, can be applied while guaranteeing the same result.\",\"PeriodicalId\":54969,\"journal\":{\"name\":\"International Journal of Computational Geometry & Applications\",\"volume\":\"81 4 1\",\"pages\":\"360-429\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2016-10-17\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Computational Geometry & Applications\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.20382/jocg.v7i1a17\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"Mathematics\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Computational Geometry & Applications","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.20382/jocg.v7i1a17","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"Mathematics","Score":null,"Total":0}
Near-linear time medial axis approximation of smooth curves in $\mathbb{R}^3$
We present the first algorithm to approximate the medial axis $M_{\gamma}$ of a smooth, closed curve $\gamma \subset \mathbb{R}^3$ in near-linear time. Our algorithm works on a sufficiently dense \eps-sample and comes with a convergence guarantee for the non-discrete, but continuous approximation object. As our approach also works correctly for a set of curves, we discuss the following application of the medial axis: The medial axis of two curves $\gamma_1$ and $\gamma_2$ can be applied to compute piecewise-linear simplifications of $\gamma_1$ and $\gamma_2$. In particular, a controllable tradeoff between the degree of simplification and the degree of falsification of the summed Fr\'{e}chet distance between $\gamma_1$ and $\gamma_2$ is obtained. Finally, we show that for simplifying $\gamma_1$ and $\gamma_2$, our approximation, instead of $M_{\gamma}$, can be applied while guaranteeing the same result.
期刊介绍:
The International Journal of Computational Geometry & Applications (IJCGA) is a quarterly journal devoted to the field of computational geometry within the framework of design and analysis of algorithms.
Emphasis is placed on the computational aspects of geometric problems that arise in various fields of science and engineering including computer-aided geometry design (CAGD), computer graphics, constructive solid geometry (CSG), operations research, pattern recognition, robotics, solid modelling, VLSI routing/layout, and others. Research contributions ranging from theoretical results in algorithm design — sequential or parallel, probabilistic or randomized algorithms — to applications in the above-mentioned areas are welcome. Research findings or experiences in the implementations of geometric algorithms, such as numerical stability, and papers with a geometric flavour related to algorithms or the application areas of computational geometry are also welcome.