Constrained shape modification of cubic B-spline curves by means of knots

نویسندگان

  • Imre Juhász
  • Miklós Hoffmann
چکیده

The effect of the modification of knot values on the shape of B-spline curves is examined in this paper. The modification of a knot of a Bspline curve of order k generates a one-parameter family of curves.This family has an envelope which is also a B-spline curve with the same control polygon and of order k 2 1: Applying this theoretical result, three shape control methods are provided for cubic B-spline curves, that are based on the modification of three consecutive knots. The proposed methods enable local shape modifications subject to position and/or tangent constraints that can be specified within well defined limits. q 2003 Published by Elsevier Science Ltd.

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عنوان ژورنال:
  • Computer-Aided Design

دوره 36  شماره 

صفحات  -

تاریخ انتشار 2004