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arXiv · 0705.3820

Maximizing Maximal Angles for Plane Straight-Line Graphs

Oswin Aichholzer·Thomas Hackl·Michael Hoffmann·Clemens Huemer·Attila Por·Francisco Santos·Bettina Speckmann·Birgit Vogtenhuber
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Abstract

Let $G=(S, E)$ be a plane straight-line graph on a finite point set $S\subset\R^2$ in general position. The incident angles of a vertex $p \in S$ of $G$ are the angles between any two edges of $G$ that appear consecutively in the circular order of the edges incident to $p$. A plane straight-line graph is called $ϕ$-open if each vertex has an incident angle of size at least $ϕ$. In this paper we study the following type of question: What is the maximum angle $ϕ$ such that for any finite set $S\subset\R^2$ of points in general position we can find a graph from a certain class of graphs on $S$ that is $ϕ$-open? In particular, we consider the classes of triangulations, spanning trees, and paths on $S$ and give tight bounds in most cases.

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Oswin Aichholzer, Thomas Hackl, Michael Hoffmann, Clemens Huemer, Attila Por, Francisco Santos, Bettina Speckmann, Birgit Vogtenhuber. 2009-10-12. Maximizing Maximal Angles for Plane Straight-Line Graphs. https://doi.org/10.1007/978-3-540-73951-7_40

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