Quasi-Upward planarity (extended abstract)

In this paper we introduce the quasi-upward planar drawing convention and give a polynomial time algorithm for computing a quasi-upward planar drawing with a minimum number of bends within a given planar embedding. Further, we study the problem of computing quasi-upward planar drawings with a minimum number of bends of digraphs considering all the possible planar embeddings. The paper contains also experimental results about proposed techniques