Strict Confluent Drawing

  • David Eppstein
  • Danny Holten
  • Maarten Löffler
  • Martin Nöllenburg
  • Bettina Speckmann
  • Kevin Verbeek
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8242)


We define strict confluent drawing, a form of confluent drawing in which the existence of an edge is indicated by the presence of a smooth path through a system of arcs and junctions (without crossings), and in which such a path, if it exists, must be unique. We prove that it is NP-complete to determine whether a given graph has a strict confluent drawing but polynomial to determine whether it has an outerplanar strict confluent drawing with a fixed vertex ordering (a drawing within a disk, with the vertices placed in a given order on the boundary).


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Copyright information

© Springer International Publishing Switzerland 2013

Authors and Affiliations

  • David Eppstein
    • 1
  • Danny Holten
    • 2
  • Maarten Löffler
    • 3
  • Martin Nöllenburg
    • 4
  • Bettina Speckmann
    • 5
  • Kevin Verbeek
    • 6
  1. 1.Computer Science DepartmentUniversity of CaliforniaIrvineUSA
  2. 2.Synerscope BVEindhovenThe Netherlands
  3. 3.Department of Computing and Information SciencesUtrecht UniversityThe Netherlands
  4. 4.Institute of Theoretical InformaticsKarlsruhe Institute of TechnologyGermany
  5. 5.Department of Mathematics and Computer ScienceTechnical University EindhovenThe Netherlands
  6. 6.Department of Computer ScienceUniversity of CaliforniaSanta BarbaraUSA

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