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GeometricObjects Interface CATNurbsCurve

GeometricObjects.CATCurve

CATNurbsCurve

Usage: an implementation of this interface is supplied and you must use it as is. You should not reimplement it.

interface CATNurbsCurve

Interface representing a Nurbs curve.
This interface is used to describe:

Bezier curves which are single-arc Nurbs
NUPBS (Non Uniform Polynomial Base Spline) which are special cases of Nurbs curves where all the weight of the control points equal to 1.

NOTE: Periodic Nurbs are not supported.
A CATNurbsCurve is created by the CATCreateNurbsCurve method of the CATGeoFactory interface and deleted with the Remove method. It is defined with:

CATKnotVector	`KnotVector`	The knot vector for the polynomial basis definition
CATMatSetOfPoints	`Vertices`	The set of control points
CATBoolean	`IsRational`	`TRUE` if the nurbs is rational, `FALSE` otherwise (NUPBS)
double[]	`Weights`	The array of weights if `IsRational`

See also:: CATKnotVector

Method Index

o GetOneControlPoint(CATLONG32,CATMathPoint&): Returns a control point of this CATNurbsCurve.
o GetOneWeight(CATLONG32): Returns the weight associated with a control point of this CATNurbsCurve.
o GetOriginalParametrisationDATA(double&,double&): Retrieves the original parameterization.
o IsRational(): Tests whether this CATNurbsCurve is rational.
o Set(CATKnotVector&,CATLONG32&,CATMathSetOfPoints&,double*,CATParameterizationOption)
o SetData(CATKnotVector&,CATLONG32&,CATMathSetOfPoints&,double*,CATParameterizationOption): Modifies the characteristics of this CATNurbsCurve.
o SetOneControlPoint(CATLONG32,CATMathPoint&): Modifies the definition of a control point of this CATNurbsCurve.
o SetOneWeight(CATLONG32,double): Modifies the weight associated with a control point of this CATNurbsCurve.

Methods

o GetOneControlPoint

public virtual void GetOneControlPoint(	CATLONG32	`iNum`,
	CATMathPoint&	`ioControlPoint`) const =0

Returns a control point of this CATNurbsCurve.

Parameters:

iNum: The control point number starting at 1.
ioControlPoint: The corresponding control point.

o GetOneWeight

public virtual double GetOneWeight( CATLONG32 iNum) const =0

Returns the weight associated with a control point of this CATNurbsCurve.

Parameters:

iNum: The control point number starting at 1.

Returns:

The weight.

o GetOriginalParametrisationDATA

public virtual void GetOriginalParametrisationDATA(	double&	`ioCoefficient`,
	double&	`ioShift`) =0

Retrieves the original parameterization.
If created with the CatAutomaticParameterization default mode by the factory, the Nurbs is internally re-parameterized. This allows you to recover the coefficient and the shift that correspond to your own parameterization
ParameterAfterCreation = ioCoefficient*ParameterBeforeCreation + ioShift in each direction.

Parameters:

ioCoefficient: The multiplicative coefficent.
ioShift: The shift.

o IsRational

public virtual CATBoolean IsRational(

)const =0

Tests whether this CATNurbsCurve is rational.

Returns:

Legal values:

FALSE: if it is not rational.
TRUE: if it is rational.

o Set

public virtual void Set(	const CATKnotVector&	`iNewKnotVector`,
	const CATLONG32&	`iNewIsRational`,
	const CATMathSetOfPoints&	`iNewVertices`,
	const double*	`iNewWeights`,
	const CATParameterizationOption	`iParameterizationOption`	`= CatAutomaticParameterization`) =0

Deprecated:: V5R14 SetData

o SetData

public virtual void SetData(	const CATKnotVector&	`iNewKnotVector`,
	const CATLONG32&	`iNewIsRational`,
	const CATMathSetOfPoints&	`iNewVertices`,
	const double*	`iNewWeights`,
	const CATParameterizationOption	`iParameterizationOption`	`= CatAutomaticParameterization`) =0

Modifies the characteristics of this CATNurbsCurve.

Parameters:

iNewKnotVector

The new definition of the polynomial basis.

NewIsRational

Legal values:

FALSE: if it is not rational.
TRUE: if it is rational.

iNewVertices

The set of control points.

iNewWeights

The array of corresponding weights (one weight per control point).

iParameterizationOption

The option of parameterization. By default, the parameterization of the NURBS is modified to better fit internal criteria. In this case, you can recover the initial parameterization with the

CATNurbsCurve.GetOriginalParametrisationDATA

o SetOneControlPoint

public virtual void SetOneControlPoint(	CATLONG32	`iNum`,
	const CATMathPoint&	`iNewCoord`) =0

Modifies the definition of a control point of this CATNurbsCurve.

Parameters:

iNum: The control point number starting at 1.
iNewCoord: The new definition of the control point.

o SetOneWeight

public virtual void SetOneWeight(	CATLONG32	`iNum`,
	double	`iNewWeight`) =0

Modifies the weight associated with a control point of this CATNurbsCurve.

Parameters:

iNum: The control point number starting at 1.
iNewWeight: The new value of the weight.

This object is included in the file: CATNurbsCurve.h
If needed, your Imakefile.mk should include the module: CATGMGeometricInterfaces