In this paper we discuss 3D rendering as a solution to the line crossing problem associated with using connecting lines for illustrating relations in visual programming. The Bezier tube was introduced for modeling connecting lines in general and hyperedges in specific and an algorithm is given for laying out hyperedges. 3D hyperedges are shown to have features that enhance their readability over that of 2D representations of connecting lines.
Lindsey L. Spratt, Allen L. Ambler