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Received: 2007-01-25

Revision Accepted: 2007-04-03

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Journal of Zhejiang University SCIENCE A 2007 Vol.8 No.10 P.1663~1670


Relation among C-curve characterization diagrams

Author(s):  CAO Juan, WANG Guo-zhao

Affiliation(s):  Institute of Computer Graphics and Image Processing, Department of Mathematics, Zhejiang University, Hangzhou 310027, China

Corresponding email(s):   cccjjqm@163.com

Key Words:  Spline, C-curve, Characterization diagram, Singularity

CAO Juan, WANG Guo-zhao. Relation among C-curve characterization diagrams[J]. Journal of Zhejiang University Science A, 2007, 8(10): 1663~1670.

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T1 - Relation among C-curve characterization diagrams
A1 - CAO Juan
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J0 - Journal of Zhejiang University Science A
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EP - 1670
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PB - Zhejiang University Press & Springer
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DOI - 10.1631/jzus.2007.A1663

As three control points are fixed and the fourth control point varies, the planar cubic c-curve may take on a loop, a cusp, or zero to two inflection points, depending on the position of the moving point. The plane can, therefore, be partitioned into regions labelled according to the characterization of the curve when the fourth point is in each region. This partitioned plane is called a “characterization diagram”. By moving one of the control points but fixing the rest, one can induce different characterization diagrams. In this paper, we investigate the relation among all different characterization diagrams of cubic c-curves based on the singularity conditions proposed by Yang and Wang (2004). We conclude that, no matter what the c-curve type is or which control point varies, the characterization diagrams can be obtained by cutting a common 3D characterization space with a corresponding plane.

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


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