Abstract
It is known that every planar graph has a planar embedding where edges are represented by non-crossing straight-line segments. We study the planar slope number, i.e., the minimum number of distinct edge-slopes in such a drawing of a planar graph with maximum degree Δ. We show that the planar slope number of every planar partial 3-tree and also every plane partial 3-tree is at most O(Δ 5). In particular, we answer the question of Dujmović et al. (Comput Geom 38(3):194–212, 2007) whether there is a function f such that plane maximal outerplanar graphs can be drawn using at most f(Δ) slopes.
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Supported by GraDR EUROGIGA project GIG/11/E023, by project 1M0021620838 of the Czech Ministry of Education, and by Grant 1M0545 of the Czech Ministry of Education.
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Jelínek, V., Jelínková, E., Kratochvíl, J. et al. The Planar Slope Number of Planar Partial 3-Trees of Bounded Degree. Graphs and Combinatorics 29, 981–1005 (2013). https://doi.org/10.1007/s00373-012-1157-z
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DOI: https://doi.org/10.1007/s00373-012-1157-z