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arXiv · 1808.10470

On RAC Drawings of Graphs with one Bend per Edge

Patrizio Angelini·Michael A. Bekos·Henry Förster·Michael Kaufmann
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Abstract

A k-bend right-angle-crossing drawing or (k-bend RAC drawing}, for short) of a graph is a polyline drawing where each edge has at most k bends and the angles formed at the crossing points of the edges are 90 degrees. Accordingly, a graph that admits a k-bend RAC drawing is referred to as k-bend right-angle-crossing graph (or k-bend RAC, for short). In this paper, we continue the study of the maximum edge-density of 1-bend RAC graphs. We show that an n-vertex 1-bend RAC graph cannot have more than $5.5n-O(1)$ edges. We also demonstrate that there exist infinitely many n-vertex 1-bend RAC graphs with exactly $5n-O(1)$ edges. Our results improve both the previously known best upper bound of $6.5n-O(1)$ edges and the corresponding lower bound of $4.5n-O(\sqrt{n})$ edges by Arikushi et al. (Comput. Geom. 45(4), 169--177 (2012)).

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Patrizio Angelini, Michael A. Bekos, Henry Förster, Michael Kaufmann. 2018-08-30. On RAC Drawings of Graphs with one Bend per Edge. https://arxiv.org/abs/1808.10470

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