Pointed drawings of planar graphs

Comput Geom. 2012 Nov;45(9):482-494. doi: 10.1016/j.comgeo.2010.08.001.


We study the problem how to draw a planar graph crossing-free such that every vertex is incident to an angle greater than π. In general a plane straight-line drawing cannot guarantee this property. We present algorithms which construct such drawings with either tangent-continuous biarcs or quadratic Bézier curves (parabolic arcs), even if the positions of the vertices are predefined by a given plane straight-line drawing of the graph. Moreover, the graph can be drawn with circular arcs if the vertices can be placed arbitrarily. The topic is related to non-crossing drawings of multigraphs and vertex labeling.

Keywords: Angular resolution; Planar drawings; Pointed pseudotriangulations.