Computational Geometry ( IF 0.6 ) Pub Date : 2021-07-29 , DOI: 10.1016/j.comgeo.2021.101819 Satyabrata Jana 1 , Anil Maheshwari 2 , Sasanka Roy 1
Let be an edge weighted geometric graph (not necessarily planar) such that every edge is horizontal or vertical. The weight of an edge is the -distance between its endpoints. Let denotes the length of a shortest path between a pair of vertices u and v in G. The graph G is said to be a Manhattan network for a given point set P in the plane if and , . In addition to P, the graph G may also include a set T of Steiner points in its vertex set V. In the Manhattan network problem, the objective is to construct a Manhattan network of small size (the number of Steiner points) for a set of n points. This problem was first considered by Gudmundsson et al. [EuroCG 2007]. They give a construction of a Manhattan network of size for general point sets in the plane. We say a Manhattan network is planar if it has a planar embedding. In this paper, we construct a planar Manhattan network for convex point sets in linear time using Steiner points. We also show that, even for convex point sets, the construction in Gudmundsson et al. [EuroCG 2007] needs Steiner points, and the network may not be planar.
中文翻译:
凸点集的线性大小平面曼哈顿网络
让 是一个边加权几何图(不一定是平面),这样每条边都是水平或垂直的。边的权重 是个 - 端点之间的距离。让表示最短路径的一对顶点之间的长度ù和v在ģ。对于平面中的给定点集P,图G被称为曼哈顿网络,如果 和 , . 除了P,图表ģ还可以包括一组Ť的斯坦纳点在其顶点集V。在曼哈顿网络问题中,目标是为一组n个点构建一个小规模(Steiner 点的数量)的曼哈顿网络。Gudmundsson 等人首先考虑了这个问题。[EuroCG 2007]。他们给出了一个曼哈顿规模的网络的构建用于平面中的一般点集。我们说曼哈顿网络是平面的,如果它有一个平面嵌入。在本文中,我们使用线性时间为凸点集构建平面曼哈顿网络施泰纳点。我们还表明,即使对于凸点集,Gudmundsson 等人的构造也是如此。[EuroCG 2007] 需要 Steiner 点,并且网络可能不是平面的。