Orthogonal Edge Visibility Graphs of Polygons with Holes.

In this paper we report on a set of six necessary conditions that must be satisfied by the edge visibility graph of an orthogonal polygon with holes. We have also proved the following significant result: If G is a connected, bipartite, planar, and irreducible (in a sense defined in the paper) graph then it can be realized (that is, there is a corresponding orthogonal polygon with holes) up to leaf addition. [ABSTRACT FROM AUTHOR]