Lecture 28: Knot Insertion Algorithms for B-spline Curves and Surfaces
نویسنده
چکیده
B-spline methods have several advantages over Bezier techniques. B-splines are piecewise polynomials that meet smoothly at their common boundaries independent of the location of the control points. This guaranteed smoothness allows designers to use low degree polynomial pieces to construct complicated freeform shapes. In addition, a control point of a B-spline curve or surface has no influence on parts of the curve or surface that are far removed from the control point. Thus B-splines provide designers with local control over the shape of a curve or surface.
منابع مشابه
Algorithms for B - patches
B-patches are the analogue to B-spline segments for triangular surfaces and are the main building block in the new multivariate B-spline surfaces recently developed in [8). This paper discusses algorithms for B-patches and presents algorithms for computing the polar form, for evaluation, for differentiation, for computing continuous joints, and for knot insertion .
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