Az Eszterházy Károly Tanárképző Főiskola Tudományos Közleményei. 2004. Sectio Mathematicae. (Acta Academiae Paedagogicae Agriensis : Nova series ; Tom. 31)

TORNAI , R. , Shape modification of cubic B-spline curves by means of knot pairs

66 R. Tornai (4) Vj-2 < Vj-l = Vj < U < V

J + 1 < V

J+

2 = V

j+

3 In this case only four of the six paths form the boundary of the area that can be seen in Fig. 1. c). Figure 1. 3.2.3. Qq: the unknowns are vj and Vj+

2 Due to the symmetry this final case is similar to the one with the unknowns vj1, Vj+

1. The four extreme cases can be described as follows (vj £ [fj-i, m], 2 £ [v

j+

1,v

J+

3] ):