Skip to main content

Guarding Orthogonal Art Galleries Using Sliding Cameras: Algorithmic and Hardness Results

  • Conference paper
Mathematical Foundations of Computer Science 2013 (MFCS 2013)

Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 8087))

Abstract

Let P be an orthogonal polygon. Consider a sliding camera that travels back and forth along an orthogonal line segment s ⊆ P as its trajectory. The camera can see a point p ∈ P if there exists a point q ∈ s such that pq is a line segment normal to s that is completely contained in P. In the minimum-cardinality sliding cameras problem, the objective is to find a set S of sliding cameras of minimum cardinality to guard P (i.e., every point in P can be seen by some sliding camera in S) while in the minimum-length sliding cameras problem the goal is to find such a set S so as to minimize the total length of trajectories along which the cameras in S travel.

In this paper, we first settle the complexity of the minimum-length sliding cameras problem by showing that it is polynomial tractable even for orthogonal polygons with holes, answering a question posed by Katz and Morgenstern [9]. Next we show that the minimum-cardinality sliding cameras problem is NP-hard when P is allowed to have holes, which partially answers another question posed by Katz and Morgenstern [9].

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 39.99
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 54.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Amit, Y., Mitchell, J.S.B., Packer, E.: Locating guards for visibility coverage of polygons. Int. J. Comput. Geometry Appl. 20(5), 601–630 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  2. Biedl, T.C., Irfan, M.T., Iwerks, J., Kim, J., Mitchell, J.S.B.: The art gallery theorem for polyominoes. Disc. & Comp. Geom. 48(3), 711–720 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  3. Chvátal, V.: A combinatorial theorem in plane geometry. J. Comb. Theory, Ser. B 18, 39–41 (1975)

    Article  MATH  Google Scholar 

  4. Fekete, S.P., Mitchell, J.S.B.: Terrain decomposition and layered manufacturing. Int. J. of Comp. Geom. & App. 11(6), 647–668 (2001)

    Article  MathSciNet  MATH  Google Scholar 

  5. Hassin, R., Megiddo, N.: Approximation algorithms for hitting objects with straight lines. Disc. App. Math. 30(1), 29–42 (1991)

    Article  MathSciNet  MATH  Google Scholar 

  6. Hoffmann, F.: On the rectilinear art gallery problem. In: Paterson, M. (ed.) ICALP 1990. LNCS, vol. 443, pp. 717–728. Springer, Heidelberg (1990)

    Chapter  Google Scholar 

  7. Kahn, J., Klawe, M.M., Kleitman, D.J.: Traditional galleries require fewer watchmen. SIAM J. on Algebraic Disc. Methods 4(2), 194–206 (1983)

    Article  MathSciNet  MATH  Google Scholar 

  8. Karp, R.M.: Reducibility among combinatorial problems. In: Complexity of Computer Computations, pp. 85–103 (1972)

    Google Scholar 

  9. Katz, M.J., Morgenstern, G.: Guarding orthogonal art galleries with sliding cameras. Int. J. of Comp. Geom. & App. 21(2), 241–250 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  10. Katz, M.J., Roisman, G.S.: On guarding the vertices of rectilinear domains. Comput. Geom. 39(3), 219–228 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  11. König, D.: Gráfok és mátrixok. Matematikai és Fizikai Lapok 38, 116–119 (1931)

    MATH  Google Scholar 

  12. Lee, D.T., Lin, A.K.: Computational complexity of art gallery problems. IEEE Trans. on Inf. Theory 32(2), 276–282 (1986)

    Article  MathSciNet  MATH  Google Scholar 

  13. Lingas, A., Wasylewicz, A., Żyliński, P.: Linear-time 3-approximation algorithm for the r-star covering problem. In: Nakano, S.-i., Rahman, M. S. (eds.) WALCOM 2008. LNCS, vol. 4921, pp. 157–168. Springer, Heidelberg (2008)

    Chapter  Google Scholar 

  14. Motwani, R., Raghunathan, A., Saran, H.: Covering orthogonal polygons with star polygons: the perfect graph approach. In: Proc. ACM SoCG, pp. 211–223 (1988)

    Google Scholar 

  15. O’Rourke, J.: Art gallery theorems and algorithms. Oxford University Press (1987)

    Google Scholar 

  16. Schuchardt, D., Hecker, H.-D.: Two NP-hard art-gallery problems for ortho-polygons. Math. Logic Quarterly 41(2), 261–267 (1995)

    Article  MathSciNet  MATH  Google Scholar 

  17. Urrutia, J.: Art gallery and illumination problems. In: Handbook of Comp. Geom., pp. 973–1027. North-Holland (2000)

    Google Scholar 

  18. Worman, C., Keil, J.M.: Polygon decomposition and the orthogonal art gallery problem. Int. J. of Comp. Geom. & App. 17(2), 105–138 (2007)

    Article  MathSciNet  MATH  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2013 Springer-Verlag Berlin Heidelberg

About this paper

Cite this paper

Durocher, S., Mehrabi, S. (2013). Guarding Orthogonal Art Galleries Using Sliding Cameras: Algorithmic and Hardness Results. In: Chatterjee, K., Sgall, J. (eds) Mathematical Foundations of Computer Science 2013. MFCS 2013. Lecture Notes in Computer Science, vol 8087. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40313-2_29

Download citation

  • DOI: https://doi.org/10.1007/978-3-642-40313-2_29

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-642-40312-5

  • Online ISBN: 978-3-642-40313-2

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics