The Effect of Knot Modifications on the Shape of B-spline Curves
نویسندگان
چکیده
This paper is devoted to the shape control of B-spline curves achieved by the modification of one of its knot values. At first those curves are described along which the points of a B-spline curve move under the modification of a knot value. Then we show that the one-parameter family of k order B-spline curves obtained by modifying a knot value has an envelope which is also a B-spline curve of order k − 1.
منابع مشابه
Knot modification of B-spline curves
The effect of knot modifications on the shape of B-spline and NURBS curves is discussed in this paper. Theoretical results include the description of the path of curve points, obtained by the modification of a knot value, and the examination of the one-parameter family of curves. It is shown that this family has an envelope which is a lower order B-spline or NURBS curve. Applying these results ...
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