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Drawing shortest paths in geodetic graphs. (English) Zbl 07436628

Auber, David (ed.) et al., Graph drawing and network visualization. 28th international symposium, GD 2020, Vancouver, BC, Canada, September 16–18, 2020. Revised selected papers. Cham: Springer. Lect. Notes Comput. Sci. 12590, 333-340 (2020).
Summary: Motivated by the fact that in a space where shortest paths are unique, no two shortest paths meet twice, we study a question posed by Greg Bodwin: Given a geodetic graph \(G\), i.e., an unweighted graph in which the shortest path between any pair of vertices is unique, is there a philogeodetic drawing of \(G\), i.e., a drawing of \(G\) in which the curves of any two shortest paths meet at most once? We answer this question in the negative by showing the existence of geodetic graphs that require some pair of shortest paths to cross at least four times. The bound on the number of crossings is tight for the class of graphs we construct. Furthermore, we exhibit geodetic graphs of diameter two that do not admit a philogeodetic drawing.
For the entire collection see [Zbl 1475.68017].

MSC:

68R10 Graph theory (including graph drawing) in computer science
68U05 Computer graphics; computational geometry (digital and algorithmic aspects)

References:

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