Drawing Graphs with Few Arcs

摘要

Let G = (V, E) be a planar graph. An arrangement of circular arcs is called a composite arc-drawing of G, if its 1-skeleton is iso-morphic to G. Similarly, a composite segment-drawing is described by an arrangement of straight-line segments. We ask for the smallest ground set of arcs/segments for a composite arc/segment-drawing. We present algorithms for constructing composite arc-drawings for trees, series-parallel graphs, planar 3-trees and general planar graphs. In the case where G is a tree, we also introduce an algorithm that realizes the vertices of the composite drawing on a O(n~(1.81)) × n grid. For each of the graph classes we provide a lower bound for the maximal size of the arrangement's ground set.