balaguer@disuns2.epfl.ch (Jean-Francis Balaguer) (11/26/90)
Here, at the Swiss Institute of Technology of Lausanne, I have a student
building a B-Spline sculptor based on
Hierarchical B-Spline Refinement
David R. Forsey and Richard H. Bartels
SIGGRAPH 88, Computer Graphics Vol 22(4), ACM
The student project is very short and we are having a small problem with
the way offsetting is done in the article.
At p.209:
" W = R + O ; i.e [W] = [R] + [O] .
i,j i,j i,j
The point R is the reference, and it is to be specified from the parent
i,j
surface. In our prototype editor R , the reference for W , is derived
i,j i,j
from the point on the surface maximally influenced by W . The components
i,j
of R are calculated from the tangent plane and the normal to the surface
i,j
at this maximally influenced point. This is, however, only one choice of
many possibilities, and an investigation of other choices is in order."
Can anybody help us how the matrix R is calculated or know any solutions to
offsetting with B-Splines, or communicate one of the authors' e-mail address?
Please mail directly answer to me pretty quick as the student project is very
short
F.Balaguer (balaguer@ligsg2.epfl.ch)
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Francis Balaguer, DI/LIG Ecole Polytechnique Fed. de Lausanne CH-1015 Lausanne
E-mail : balaguer@ligsg2.epfl.ch, balaguer@elma.epfl.ch
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