MINGLE
Multiresolution in Geometric Modelling
Home
Research Topic
Partners
Positions Available
Events
Visitors
Publications
Data Sets
Links
Ioannis Ivrissimtzis
Name: Ioannis Ivrissimtzis
E-mail: ipi20@cl.cam.ac.uk
Homepage: http://www.cl.cam.ac.uk/~ipi20
Host institution: University of Cambridge Computer Laboratory (UCAM-CLAB), UK
Period of visit: September 2000 - September 2001

Project descriptions
During his visit, Ioannis has been working on the following projects:
  • Recursive subdivision

    Recursive subdivision is an efficient tool for the fast generation of high quality surfaces. The basic idea is the progressive refinement of a coarse polyhedron, by computing in each step new vertices and joining them up with edges to form a new polyhedron. This way we create a hierarchy of polyhedra which under certain conditions converges to a smooth limit surface. For computing efficiency, and simplicity, the most of the known subdivision schemes compute the new vertices as linear combinations of the existing ones. Our research aims at developing methods to calculate the coefficients of these linear combinations in an argued, constructive way, rather than by solving an optimisation problem.

    To do this, instead of projecting locally the polyhedron on the Euclidean plane, we project it on a sphere or a hyperboloid, and then work out the coefficients of the scheme taking into account the induced spherical or hyperbolic geometry. Our methods give simple algorithms for the calculation of the coefficients of the scheme, give new insights into well-known schemes, and can also be used in the artifact analysis.


Publications
The following publications summarize some of the results of the research work that Ioannis has participated in during his stay:
  • "Geometric Analysis of Recursive Subdivision"
    by Ioannis Ivrissimtzis, Mo Hassan, Malcolm Sabin, Neil Dodgson
    in preparation

  • "An Interpolating 4-point C2 Ternary Stationary Subdivision Scheme"
    by Mo Hassan, Ioannis Ivrissimtzis, Malcolm Sabin, Neil Dodgson
    in preparation

Conferences
Ioannis was sponsored by MINGLE to participate in the following conferences and workshops:
  • IX IMA Conference on the Mathematics of surfaces, September 3-6, 2000, Cambridge, UK

  • MINGLE workshop, January 18-19, 2001, Grenoble, France,
    giving a talk about "Geometric Analysis of Recursive Subdivision"



Prepared by: SINTEF Applied Mathematics & TECHNION, Computer Science Dept.
Last update: November 26, 2000 | Vitaly Surazhsky