IWOCA 2011: Combinatorial Algorithms pp 156-169

# 2-Layer Right Angle Crossing Drawings

• Emilio Di Giacomo
• Walter Didimo
• Giuseppe Liotta
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7056)

## Abstract

A 2-layer drawing represents a bipartite graph so that the vertices of each partition set are points of a distinct horizontal line (called a layer) and the edges are straight-line segments. In this paper we study 2-layer drawings where all edge crossings form right angles. We characterize which graphs admit this type of drawing, provide linear-time testing and embedding algorithms, and present a polynomial-time crossing minimization technique. Also, for a given graph G and a constant k, we prove that it is $$\mathcal{NP}$$-complete to decide whether G contains a subgraph of at least k edges having a 2-layer drawing with right angle crossings.

## Keywords

Bipartite Graph Internal Vertex Span Subgraph Edge Crossing Independent Edge
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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## Authors and Affiliations

• Emilio Di Giacomo
• 1
• Walter Didimo
• 1