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CLC number: TN391.72

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Received: 2008-11-26

Revision Accepted: 2009-02-16

Crosschecked: 2009-02-16

Cited: 4

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Citations:  Bibtex RefMan EndNote GB/T7714

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Journal of Zhejiang University SCIENCE A 2009 Vol.10 No.4 P.570-576


NURBS curve blending using extension

Author(s):  Yong-jin LIU, Rong-qi QIU, Xiao-hui LIANG

Affiliation(s):  Tsinghua National Lab for Information Science and Technology, Tsinghua University, Beijing 100084, China; more

Corresponding email(s):   liuyongjin@tsinghua.edu.cn

Key Words:  Curve blending, Curve fairing, Curve extension, Non-uniform rational B-spline (NURBS)

Yong-jin LIU, Rong-qi QIU, Xiao-hui LIANG. NURBS curve blending using extension[J]. Journal of Zhejiang University Science A, 2009, 10(4): 570-576.

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Curve and surface blending is an important operation in CAD systems, in which a non-uniform rational B-spline (NURBS) has been used as the de facto standard. In local corner blending, two curves intersecting at that corner are first made disjoint, and then the third blending curve is added-in to smoothly join the two curves with G1- or G2-continuity. In this paper we present a study to solve the joint problem based on curve extension. The following nice properties of this extension algorithm are exploited in depth: (1) The parameterization of the original shapes does not change; (2) No additional fragments are created. Various examples are presented to demonstrate that our solution is simple and efficient.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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[9] Zang, Y., Liu, Y., Lai, Y., 2008. Note on industrial applications of Hu’s surface extension algorithm. LNCS, 4975:304-314.

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