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I/o-efficient efficient algorithms for computing contours on a terrain

Published: 09 June 2008 Publication History

Abstract

A terrain M is the graph of a bivariate function. We assume that M is represented as a triangulated surface with N vertices. A contour (or isoline) of M is a connected component of a level set of M. Generically, each contour is a closed polygonal curve; at "critical" levels these curves may touch each other or collapse to a point. We present I/O efficient algorithms for the following two problems related to computing contours of M:
(i) Given a sequence l1 < ... < ls of real numbers, we present an I/O-optimal algorithm that reports all contours of M at heights l1, ..., ls using O(sort(N) + T/B) I/Os, where T is the total number edges in the output contours, B is the "block size," and sort(N) is the number of I/Os needed to sort N elements. The algorithm uses O(N/B) disk blocks. Each contour is generated individually with its composing segments sorted in clockwise or counterclockwise order. Moreover, our algorithm generates information on how the contours are nested.
(ii) We can preprocess M, using O(sort(N)) I/Os, into a linear-size data structure so that all contours at a given height can be reported using O(logB N + T/B) I/Os, where T is the output size. Each contour is generated individually with its composing segments sorted in clockwise or counterclockwise order.

References

[1]
P. K. Agarwal, L. Arge, T. M. Murali, K. R. Varadarajan, and J. S. Vitter, I/O-efficient algorithms for contour-line extraction and planar graph blocking, Proc. 9th ACM-SIAM Sympos. Discrete Algorithms, 1998, pp. 117--126.
[2]
P. K. Agarwal, L. Arge, and K. Yi, I/O-efficient batched union-find and its applications to terrain analysis, Proc. 22nd Annu. ACM Sympos. Comput. Geom., 2006, pp. 167--176.
[3]
A. Aggarwal and J. S. Vitter, The input/output complexity of sorting and related problems, Commun. ACM, 31 (1988), 1116--1127.
[4]
L. Arge, External memory data structures, in: Handbook of Massive Data Sets (J. Abello, P. M. Pardalos, and M. G. C. Resende, eds.), Kluwer Academic Publishers, 2002, pp. 313--358.
[5]
L. Arge, The buffer tree: A technique for designing batched external data structures, Algorithmica, 37 (2003), 1--24.
[6]
L. Arge, A. Danner, and S.-H. Teh, I/O-efficient point location using persistent B-trees, Proc. Workshop on Algorithm Engineering and Experimentation, 2003.
[7]
L. Arge, K. H. Hinrichs, J. Vahrenhold, and J. S. Vitter, Efficient bulk operations on dynamic R-trees, Algorithmica, 33 (2002), 104--128.
[8]
L. Arge, L. Toma, and N. Zeh, I/O-efficient topological sorting of planar dags, Proc. 15th Annu. ACM Sympos. Parallel Algorithms and Architectures, 2003, pp. 85--93.
[9]
H. Carr, J. Snoeyink, and U. Axen, Computing contour trees in all dimensions, Computational Geometry: Theory and Applications, 24 (2003), 75--94.
[10]
Y.-J. Chiang, M. T. Goodrich, E. F. Grove, R. Tamassia, D. E. Vengroff, and J. S. Vitter, External-memory graph algorithms, Proc. 6th ACM-SIAM Sympos. Discrete Algorithms, 1995, pp. 139--149.
[11]
Y.-J. Chiang and C. T. Silva, I/O optimal isosurface extraction, Proc. IEEE Visualization, 1997, pp. 293--300.
[12]
A. Danner, T. Mølhave, K. Yi, P. K. Agarwal, L. Arge, and H. Mitasova, TerraStream: From elevation data to watershed hierarchies, Proc. ACM Sympos. on Advances in Geographic Information Systems, 2007, 212--219.
[13]
H. Edelsbrunner, D. Letscher, and A. Zomorodian, Topological persistence and simplification, Discrete Comput. Geom., 28 (2002), pp. 511--533.
[14]
I. Fáry, On straight lines representation of planar graphs, Acta Sci. Math. Szeged, 11 (1948), 229--233.
[15]
M. Isenburg, Y. Liu, J. Shewchuk, and J. Snoeyink, Streaming computation of Delaunay triangulations, Proc. of SIGGRAPH, 2006, pp. 1049--1056.
[16]
W. Lorensen and H. Cline, Marching cubes: a high resolution 3d surface construction algorithm, Comput. Graph., 21 (1987), 163--170.
[17]
M. H. Nodine, M. T. Goodrich, and J. S. Vitter, Blocking for external graph searching, Algorithmica, 16 (1996), 181--214.
[18]
C. Silva, Y. Chiang, J. El-Sana, and P. Lindstrom, Out-of-core algorithms for scientific visualization and computer graphics, Visualization'02, 2002. Course Notes for Tutorial 4.
[19]
R. A. Skelton, Cartography, History of Technology, 6 (1958), 612--614.
[20]
J. van den Bercken, B. Seeger, and P. Widmayer, A generic approach to bulk loading multidimensional index structures, Proc. International Conference on Very Large Databases, 1997, pp. 406--415.
[21]
M. van Kreveld, R. van Oostrum, C. Bajaj, V. Pascucci, and D. Schikore, Contour trees and small seed sets for isosurface traversal, Proc. 13th Annu. ACM Sympos. Comput. Geom., 1997, pp. 212--219.
[22]
P. J. Varman and R. M. Verma, An efficient multiversion access structure, IEEE Transactions on Knowledge and Data Engineering, 9 (1997), 391--409.
[23]
J. S. Vitter, External memory algorithms and data structures: Dealing with MASSIVE data, ACM Computing Surveys, 33 (2001), 209--271.

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    cover image ACM Conferences
    SCG '08: Proceedings of the twenty-fourth annual symposium on Computational geometry
    June 2008
    304 pages
    ISBN:9781605580715
    DOI:10.1145/1377676
    Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

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    Publication History

    Published: 09 June 2008

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    Author Tags

    1. contours
    2. geographical information systems
    3. i/o-efficient algorithms
    4. terrains

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    SoCG08
    SoCG08: 24th Annual Symposium on Computational Geometry
    June 9 - 11, 2008
    MD, College Park, USA

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    • (2011)I/O-efficient contour queries on terrainsProceedings of the twenty-second annual ACM-SIAM symposium on Discrete algorithms10.5555/2133036.2133059(268-284)Online publication date: 23-Jan-2011

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