SEFE

Beyond level planarity: Cyclic, torus, and simultaneous level planarity

In this paper we settle the computational complexity of two open problems related to the extension of the notion of level planarity to surfaces different from the plane. Namely, we show that the problems of testing the existence of a level embedding …

Clustered Planarity with Pipes

In this paper we study the version of the C-Planarity problem in which edges connecting the same pair of clusters must be grouped into pipes, which generalizes the Strip Planarity problem. We give algorithms to decide several families of instances …

Planarity of Streamed Graphs

In this research we introduce a notion of planarity for graphs that are presented in a streaming fashion. A streamed graph is a stream of edges $e_1,e_2,\dots,e_m$ on a vertex set $V$. A streamed graph is $\omega$-stream planar with respect to a …

Intersection-Link Representations of Graphs

We consider drawings of graphs that contain dense subgraphs. We introduce intersection-link representations for such graphs, in which each vertex $u$ is represented by a geometric object $R(u)$ and in which each edge $(u,v)$ is represented by the …

Beyond Level Planarity

In this paper we settle the computational complexity of two open problems related to the extension of the notion of level planarity to surfaces different from the plane. Namely, we show that the problems of testing the existence of a level embedding …

Clustered Planarity with Pipes

In this paper we study the version of the C-Planarity problem in which edges connecting the same pair of clusters must be grouped into pipes, which generalizes the Strip Planarity problem. We give algorithms to decide several families of instances …

Computing NodeTrix Representations of Clustered Graphs

NodeTrix representations are a popular way to visualize clustered graphs; they represent clusters as adjacency matrices and inter-cluster edges as curves connecting the matrix boundaries. We study the complexity of constructing NodeTrix …

Simultaneous Orthogonal Planarity

We introduce and study the OrthoSEFE-$k$ problem$:$ Given~$k$ planar graphs each with maximum degree 4 and the same vertex set, is there an assignment of the vertices to grid points and of the edges to paths on the grid such that the same edges in …

SEFE = C-Planarity?

In this article, we deepen the understanding of the connection between two long-standing graph drawing open problems, Simultaneous Embedding with Fixed Edges (SEFE-2) and Clustered Planarity (C-Planarity). Given two planar graphs on the same set of …

Planar Graphs with Vertices in Prescribed Regions: models, algorithms, and complexity

The volume and the complexity of structured relational information created and handled by modern information systems has drastically increased. More and more often, data are generated so quickly that they cannon even be completely displayed or …