This class contains data that defines a NurbCurve2d object. 

If the NurbCurve2d is not periodic, the length of knot vector will be greater than length of the control array by degree+1. 

If the NurbCurve2d is periodic, the length of knot vector will be greater than length of the control array by 1.

Public Structure NurbCurve2dData
End Structure

public struct NurbCurve2dData {
}