Abstract
We define the notion of a “star unfolding” of the surface P of a convex polytope with n vertices and use it to construct an algorithm for computing a small superset of the set of all sequences of edges traversed by shortest paths on P. It requires O(n 6) time and produces O(n 6) sequences, thereby improving an earlier algorithm of Sharir that in O(n 8 log n) time produces O(n 7) sequences. A variant of our algorithm runs in O(n 5 log n) time and produces a more compact representation of size O(n 5) for the same set of O(n 6) sequences. In addition, we describe an O(n 10) time procedure for computing the geodesic diameter of P, which is the maximum possible separation of two points on P, with the distance measured along P, improving an earlier O(n 14 log n) algorithm of O'Rourke and Schevon.
Extended Abstract
Part of the work was carried out when the first two authors were at Courant Institute of Mathematical Sciences, New York University and the fourth author was at the Department of Computer Science, The Johns Hopkins University. The work of the second author was partially supported by an AT&T Bell Laboratories Ph.D. Scholarship. The work of the first two authors has also been partially supported by Dimacs (Center for Discrete Mathematics and Theoretical Computer Science), a National Science Foundation Science and Technology Center — NSF-STC88-09648. The third author's work is supported by NSF grant CCR-882194.
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References
J.L. Bentley and T.A. Ottmann, “Algorithms for reporting and counting geometric intersections,” IEEE Transactions on Computers C-28 (1979), 643–647.
J. Chen and Y. Han, “Shortest paths on a polyhedron,” to appear in Proc. of 6th ACM Symp. on Comput. Geom., 1990.
J. Chen and Y. Han, “Shortest paths on a polyhedron, part II: Storing shortest paths,” Tech. Report 161-90, Dept. of Comp. Sci., Univ. of Kentucky, Lexington, February, 1990.
H. Edelsbrunner, L. Guibas and J. Stolfi, “Optimal point location in a monotone planar subdivision,” SIAM J. Computing 15 (1986), 317–340.
H. El Gindy and D. Avis, “A linear algorithm for computing the visibility polygon from a point,” J. Algorithms 2 (1981), 186–197.
Y. Hwang, C. Chang and H. Tu, “Finding all shortest path edge sequences on a convex polyhedron,” in Workshop on Algorithms and Data Structures, Lectures Notes in Computer Science, 382 (1989), Springer-Verlag, pp. 251–266.
S. Kobayashi, “On conjugate and cut loci,” in Studies in Global Geometry and Analysis, S. S. Chern, Ed., Mathematical Association of America, 1967, pp. 96–122.
D. Mount, “On finding shortest paths on convex polyhedra,” Tech. Report 1495, University of Maryland, 1985.
D. Mount, “The number of shortest paths on the surface of a polyhedron,” Tech. Report (July 9, 1987), University of Maryland, 1987.
J. O'Rourke and C. Schevon, “Computing the geodesic diameter of a 3-polytope,” In Proc. 5th ACM Symp. Computational Geometry, June 1989, pp. 370–379.
C. Schevon and J. O'Rourke, “The number of maximal edge sequences on a convex polytope” In Proc. 26th Annual Allerton Conference on Communication, Controls, and Computing, University of Illinois at Urbana-Champaign, October 1988, pp. 49–57.
C. Schevon and J. O'Rourke, “An algorithm to compute edge sequences on a convex polytope,” Tech. Report JHU-89-3, Dept. of Computer Science, The Johns Hopkins University, Baltimore, Maryland, 1989.
M. Sharir and A. Schorr, “On shortest paths in polyhedral spaces,” SIAM J. Comput. 15 (1986), 193–215.
M. Sharir, “On shortest paths amidst convex polyhedra,” SIAM J. Comput. 16 (1987), 561–572.
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© 1990 Springer-Verlag Berlin Heidelberg
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Agarwal, P.K., Aronov, B., O'Rourke, J., Schevon, C.A. (1990). Star unfolding of a polytope with applications. In: Gilbert, J.R., Karlsson, R. (eds) SWAT 90. SWAT 1990. Lecture Notes in Computer Science, vol 447. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-52846-6_94
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DOI: https://doi.org/10.1007/3-540-52846-6_94
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