Blending method for accomplishing continuity at boundary of two b-spline curves / surfaces for use in a computing apparatus

摘要

An algebraic blending method accomplishes continuity of two n-the order curves or curved surface patch by generating a new control point of boundary by using a simple algebraic blending method in modeling a free curves/curved surface constructed by a B-spline. At a first step, a B-spline curved surface patch is obtained by using universal parametrization. At a second step, two adjacent patch to be connected with continuity is selected among the patch obtained at the first step. At a third step, at least one control point of a large patch is obtained by obtaining control points of the selected two curved surfaces and blending superposed control points. At a final step, a B-spline curved surface patch is obtained by using the obtained control points of the large patch and the two patch of the original model is replaced with the B-spline curved surface patch.