Discrete & Computational Geometry

, Volume 42, Issue 2, pp 219–223 | Cite as

Blocking Visibility for Points in General Position

  • Jiří MatoušekEmail author


For a finite set P in the plane, let b(P) be the smallest possible size of a set Q, QP=, such that every segment with both endpoints in P contains at least one point of Q. We raise the problem of estimating b(n), the minimum of b(P) over all n-point sets P with no three points collinear. We review results providing bounds on b(n) and mention some additional observations.


Visibility Visibility-blocking set Behrend’s construction 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Applied Mathematics and Institute of Theoretical Computer Science (ITI)Charles UniversityPraha 1Czech Republic
  2. 2.Institute of Theoretical Computer ScienceETH ZurichZurichSwitzerland

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