ON_SubD::SubDFriendlyKnotType identifies the types of subd friendly NURBS knot vectors.
SubD friendly NURBS curves and surfacaes are always cubic and nonrational.
Any time there is a multiple knot, the 2nd derivative is zero at the corresponding parameter.
SubD friendly NURBS curves are either periodic or have zero 2nd derivative at the ends.
RhinoCommon (in RhinoCommon.dll)
public enum SubDFriendlyKnotType
Public Enumeration SubDFriendlyKnotType
Not a valid type. Used to indicate the type has not been set and to encourage developers to explicitly specify a type.
NURBS knot vector is an unclamped uniform cubic knot vector.
Every knot interval has the same length.
Every knot has multiplicity 1.
NURBS knot vector is a clamped uniform cubic knot vector.
Every interior knot interval has the same length.
End knots have multiplicity 3 and interior knots have multiplicity 1.
NURBS knot vector is a clamped piecewise uniform cubic knot vector.
All nonzero knot intervals have the same length.
End knots have multiplicity 3 and interior knots have multiplicity 1 or 3.
Interior knots with multiplicity 3 correspond to interior SubD creases.
NURBS knot vector is not subd friendly.