CIS6930: COMPUTATIONAL GEOMETRY

Term: Fall 2004
Time: Tuesday 11:45am-1:40pm, Thursday 12:50pm-1:40pm
Location: Turlington 2336
Office hours: Tuesday 1:45pm-2:45pm, Thursday 1:45pm-2:45pm
Professor: Alper Üngör

syllabus announcements schedule projects references

Announcements

Schedule

Date Lecture Topic Assignments Speaker
Aug 24 Tu Introduction, syllabus, course structure, etc. HW#0 out
[ps, pdf]
A
  CONVEX HULLS ALGORITHMS [BKOS00, Chapter 1]    
Aug 26 Th Convex hulls
Orientation test; Degenaracy; Jarvis' march [J73]
  A
Aug 31 Tu Convex hulls
Divide & conquer; Graham's scan [G72, A79]; Chan's alg.[C96]
  A
  PLANE-SWEEP ALGORITHMS [BKOS00, Chapters 2 and 3 ]    
Sep 2 Th Line segment intersections
Plane-sweep [BO79];
  A
Sep 7 Tu Hurricane Frances (all UF classes cancelled)
Sep 9 Th Doubly-connected Edge list [BKOS00]
Half-edge data structure [CGAL]
HW#0 due A
Sep 14 Tu Subdivision Overlays
Map overlays, intersection, union, difference [BKOS00]
HW#1[ps, pdf] out
A
Sep 16 Th Art Gallery Problems [BKOS00]
Art gallery theorem [C83]
  A
Sep 21 Tu INTERNATIONAL MESHING ROUNTABLE (no class)
Sep 23 Th Polygon Triangulation
Partitioning simple polygons [LP77];
triangulating monotone polygons [GJPT78]
  A
  ORTHOGONAL SEARCH [BKOS00, Chapters 5 and 10]    
Sep 28 Tu Geometric data structures; Range search
Quad-tree; kd-tree [B75];
HW#1 due A
Sep 30 Th Improvements on Range Searching
Range tree; fractional cascading [CG86]
  A
Oct 5 Tu Inverse Range Search
Segment tree [B77]; interval tree [E83]; priority search tree [M85]
  A
Oct 7 Th Open problems and Project Ideas
HW#2 out [ps, pdf]
HW#1 graded
A
  VORONOI DIAGRAMS & DELAUNAY TRIANGULATIONS
[BKOS00, Chapters 7, 9, and 14]
   
Oct 12 Tu Voronoi diagrams
Voronoi diagrams [AK00]; largest empty disk;
Fortune's algorithm
  A
Oct 14 Th Delaunay triangulation
HW#2 due A
Oct 19 Tu Project proposal presentations Proposals due  
Oct 21 Th Project proposal presentations    
Oct 26 Tu Optimal triangulations
Empty circles, local Delaunayhood [D34],
edge-flip [L77], lifting, analysis, maxmin angles
HW#2 graded A
Oct 28 Th Randomized incremental algorithm
Incremental construction [GKS92]; backward analysis [S93]
HW#3 out [ps, pdf]
A
Nov 2 Tu Steiner triangulations
Steiner triangulation [BE95]; quality measure; quad-trees [BE95];
local feature size
  A
Nov 4 Th Delaunay refinement
Circumcenter insertion [R95];
HW#3 due A
Nov 9 Tu Surface reconstruction and simplification
Crust algorithm; Edge contraction [GH97]; topology preservation [DEGN99];
HW#3 graded A
Nov 11 Th VETERANS DAY
  ARRANGEMENTS [BKOS00, Chapter 8]    
Nov 16 Tu Zones
Duality; line arrangements; complexity;
incremental algorithm; zone theorem [ESS93]
  A
Nov 18 Th Levels and discrepancy
Super-sampling for rendering; Half-plane discrepancy[EG89]
  A
  OTHER GEOMETRY APPLICATIONS [BKOS00, Chapters 13 and 15]    
Nov 23 Tu Motion Planning
Robotics; Configuration Space; Connectedness;
Visibility Graphs; Protein Docking
HW#4 out [ps, pdf] A
Nov 25 Th THANSGIVING BREAK
Nov 30 Tu Project Presentations
   
Dec 2 Th Project Presentations HW#4 due
Reports due
 
Dec 7 Tu Final Exam (in-class, closed book)    

References

Books
[BKOS00] M. de Berg, M. van Kreveld, M. Overmars, and O. Schwarzkopf. Computational Geometry: Algorithms and Applications. Springer-Verlag, 2nd edition, 2000. [course textbook]
Surveys
[BE95] M. Bern and D. Eppstein. Mesh generation and optimal triangulation. Computing in Euclidean Geometry (2nd ed.), D.-Z. Du and F. Hwang (eds.), World Scientific, 1995, 47-123.
[E00] H. Edelsbrunner. Triangulations and meshes in computational geometry. Acta Numerica (2000), 133-213.

Other Papers
[A79] A. M. Andrew. Another efficient algorithm for convex hulls in two dimensions. Information Processing Letters, 9:216-219, 1979. [A left-to-right variant of Graham's scan]
[AK00] F. Aurenhammer and R. Klein. Voronoi Diagrams. Handbook of Computational Geometry, Ed. J. Sack, J. Urrutia (eds.), 2000, 201-290.
[B75] J. L. Bentley. Solution to Klee's rectangle problems. Tech. Rep., Carnegie-Mellon Univ., Pittsburgh, 1975.
[BO79] J. L. Bentley and T. A. Ottmann. Algorithms for reporting and counting geometric intersections. IEEE Transactions on Computers, C-28:643-647, 1979.
[C96] T. Chan. Optimal output-sensitive convex hull algorithms in two and three dimensions. Discrete and Computational Geometry, 16:361-368, 1996.
[CG86] B. Chazelle and L. J. Guibas. Fractional cascading. Algorithmica 1:133-162 and 163-191, 1986.
[C83] V. Chvatal. A combinatorial theorem in plane geometry. J. Combin. Theory Ser. B 18:39-41, 1975.
[D34] B. N. Delaunay. Sur la Sphere vide. Izvestia Akademia Nauk SSSR, VII Seria, Otdelenie Matematicheskii i Estestvennyka Nauk 7:793-800, 1934.
[DEGN99] T. K. Dey, H. Edelsbrunner, S. Guha and D. V. Nekhayev. Topology preserving edge contraction. Publications de l'Institut Mathematique (Beograd) (N. S.) 66:23-45, 1999.
[E83] H. Edelsbrunner. A new approach to rectangle intersections. International Journal Computational Mathematics 13:209-219 and 221-229, 1983.
[EG89] H. Edelsbrunner and L. J. Guibas. Topologically sweeping an arrangement. Journal Computer and System Sciences 38:165-194, 1989. Corrigendum. Journal Computer and System Sciences 42:249-251, 1991.
[ESS93] H. Edelsbrunner, R. Seidel and M. Sharir. On the zone theorem for hyperplane arrangements. SIAM Journal on Computing 22:418-429, 1993.
[ESU04] D. Eppstein, J. Sullivan and A. Üngör. Computational Geometry: Theory and Applications, 27:237-255, 2004.
[GJPT78] M. R. Garey, D. S. Johnson, F. P. Preparata, and R. E. Tarjan. Triangulating a simple polygon. Information Processing Letters, 7:175-179, 1978.
[GH97] M. Garland and P. S. Heckbert. Surface simplification using quadratic error metrics. Computer Graphics, Proc. SIGGRAPH, 209-216, 1997.
[G72] R. L. Graham. An efficient algorithm for determining the convex hull of a finite planar set. Information Processing Letters, 1:132-133, 1972.
[G72] B. Grunbaum. Arrangements and Spreads. American Mathematical Society, Providence, Rhode Island, 1972.
[GKS92] L. J. Guibas, D. E. Knuth, M. Sharir. Randomized incremental construction of Delaunay and Voronoi diagrams. Algorithmica 7:381-413, 1992.
[J73] R. A. Jarvis. On the identification of the convex hull of a finite set of points in the plane. Information Processing Letters, 2:18-21, 1973.
[KM58] L. M. Kelly and W. O. J. Moser. On the number of ordinary lines deternined by n points. Canadian Journal Mathematics, 10:210-219, 1958.
[Kir83] D. G. Kirkpatrick. Optimal search in planar subdivisions. SIAM J. Computing, 12:28-35, 1983.
[L77] C. L. Lawson. Software for C1 surface interpolation. Mathematical Software III, J. Rice ed., Academic Press, New York, 1977, 161-194.
[LP77] D. T. Lee and F. P. Preparata. Location of a point in a planar subdivision and its applications. SIAM J. Computing, 6:594-606, 1977.
[M85] E. M. McCreight. Priority search trees. SIAM Journal on Computing, 14:257-276, 1985.
[NP82] J. Nievergelt and F. P. Preparata. Plane-sweep algorithms for intersecting geometric figures. Communications of the ACM, 25:739-747, 1982.
[R95] J. Ruppert. A Delaunay refinement algorithm for quality 2-dimensional mesh generation. Journal of Algorithms, 18:548-585, 1995.
[S93] R. Seidel. Backward analysis of randomized geometric algorithms. New Trends in Computational Geometry, J. Pach ed., Springer-Verlag, Berlin, 37-67, 1993.

Links
[TOPP] The Open Problems Project by Erik D. Demaine - Joseph S. B. Mitchell - Joseph O'Rourke
[OP] Open Problems by Jeff Erickson
[OPDCG] Open Problems on Discrete and Computational Geometry by Jorge Urrutia
[SP] Sample Computational Geometry Projects from McGill University

Animations

syllabus announcements schedule projects references


Alper Üngör (ungor@cise.ufl.edu) August 2004