Least squares degree reduction of Bézier curves

Abstract In this paper we investigate the problem of reducing the degree of Bezier curves approximately from n to a prescribed target degree m whereby (parametric) continuity of any order ≤ m−1 2 can be preserved at the two endpoints. The computations are carried out by minimizing the (constrained) L2-norm between the two curves. In addition, a complete algorithm is given for performing the degree reduction within a prescribed error tolerance by help of subdivision. This work is an evident improvement on a previous paper (Eck M Comput.-Aided Geom. Des. Vol 10 (1993) pp 237–251) about degree reduction in the sense that the algorithm presented is faster and much easier to implement, while still producing very good results.

[1]  Tom Lyche,et al.  Mathematical methods in computer aided geometric design , 1989 .

[2]  G. Watson Approximation theory and numerical methods , 1980 .

[3]  Rene F. Swarttouw,et al.  Orthogonal polynomials , 2020, NIST Handbook of Mathematical Functions.

[4]  Horst Nowacki,et al.  Approximate conversion of surface representations with polynomial bases , 1985, Comput. Aided Geom. Des..

[5]  G. Alexits Approximation theory , 1983 .

[6]  Matthias Eck,et al.  Degree Reduction of Bézier Surfaces , 1992, IMA Conference on the Mathematics of Surfaces.

[7]  E. Cheney Introduction to approximation theory , 1966 .

[8]  Matthias Eck,et al.  Degree reduction of Bézier curves , 1993, Comput. Aided Geom. Des..

[9]  A. J. Worsey,et al.  Degree reduction of Be´zier curves , 1988 .

[10]  Nicholas M. PATRIKALAKIS Approximate conversion of rational splines , 1989, Comput. Aided Geom. Des..

[11]  Wendelin L. F. Degen,et al.  Best Approximations of Parametric Curves by Splines , 1992, Geometric Modelling.

[12]  Josef Hoschek Approximate conversion of spline curves , 1987, Comput. Aided Geom. Des..

[13]  Michael A. Lachance,et al.  Chebyshev economization for parametric surfaces , 1988, Comput. Aided Geom. Des..

[14]  A. Robin Forrest,et al.  Interactive interpolation and approximation by Bezier polynomials , 1972, Comput. J..