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Graphics Programming. Lee Byung-Gook Dongseo Univ. http://kowon.dongseo.ac.kr/~lbg/. Affine combination. Linear combinations Affine(Barycentric) combinations Convex combinations Barycentric coordinates. Affine combination. Euclidean coordinate system. Coordinate-free system.
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Graphics Programming Lee Byung-Gook Dongseo Univ. http://kowon.dongseo.ac.kr/~lbg/ Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Affine combination • Linear combinations • Affine(Barycentric) combinations • Convex combinations • Barycentric coordinates Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Affine combination Euclidean coordinate system Coordinate-free system Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Polynomial interpolation Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Polynomial interpolation • Lagrange polynomials Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Examples of cubic interpolation Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Bezier Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Representation Bezier Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Properties of Bezier • Affine invariance • Convex hull property • Endpoint interpolation • Symmetry • Linear precision • Pseudo-local control • Variation Diminishing Property Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Bezier • Paul de Faget de Casteljau, Citroen, 1959 • Pierre Bezier, Renault, UNISUF system, 1962 • A.R. Forrest, Cambridge, 1970 Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Piecewise cubic hermite interpolation Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Cubic spline interpolation Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Cubic spline interpolation Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Spline interpolation based on the 1-norm Cubic Spline Interpolation with Natural boundary condition Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Spline curves • J. Ferguson , Boeing Co., 1963 • C. de Boor, W. Gordon, General Motors, 1963 • to interpolate given data • piecewise polynomial curves with certain differentiability constraints • not to design free form curves Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline • C. de Boor, 1972 • W. Gordon, Richard F. Riesenfeld, 1974 • Larry L. Schumaker • Tom Lyche • Nira Dyn Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Linear splines Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Quadratic splines Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Quadratic splines Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Representation splines Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline • Recurrence Relation • Bernstein polynomial Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline • Smoothness=Degree-Multiplicity Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline basis functions Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Refinement relation for B-spline Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Repeated integration for B-spline Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Truncated powers for B-spline Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Cross-sectional Volumes Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Cross-sectional Volumes for subcubes Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Box-spline as Cross-sectional Volumes Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Bivariate Box spline over triangular grid Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Spline space Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Univariate spline Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Cubic splines Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Condition number Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Condition number of B-spline basis Tom Lyche and Karl Scherer, On the p-norm condition number of the multivariate triangular Bernstein basis, Journal of Computational and Applied Mathematics 119(2000) 259-273 Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Stability Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Blossom Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
Blossom Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr
B-spline problems • Degree Elevation • Degree Reduction • Knot Insertion • Knot Deletion Gerald Farin, Curves and Surfaces for Computer Aided Geometric Design, 4th ed, Academic Press (1996) Ronald N. Goldman, Tom Lyche, editors, Knot Insertion and Deletion Algorithms for B-Spline Curves and Surfaces, SIAM (1993) Graphics Programming 2003, Lee Byung-Gook, Dongseo Univ., E-mail:lbg@dongseo.ac.kr