Refinement of Orthogonal Graph Drawings

Current orthogonal graph drawing algorithms produce drawings which are generally good. However, many times the readability of orthogonal drawings can be signiicantly improved with a postprocess-ing technique, called reenement, which improves aesthetic qualities of a drawing such as area, bends, crossings, and total edge length. Reene-ment is separate from layout and works by analyzing and then ne-tuning the existing drawing in an eecient manner. In this paper we deene the problem and goals of orthogonal drawing reenement and introduce a methodology which eeciently reenes any orthogonal graph drawing. We have implemented our technique in C++ and conducted preliminary experiments over a set of drawings from ve well known orthogonal drawing systems. Experimental analysis shows our technique to produce an average 34% improvement in area, 22% in bends, 19% in crossings, and 34% in total edge length.