Construct NurbsSurfaceData based on NURBS surface data, where the weights are supplied. The NURBS surface will be (piecewise) polynomial if all the weights are equal, rational if not. Note: A rational polynomial is a quotient of two polynomials; this includes a polynomial, which can be thought of as a quotient with denominator equal to 1.

Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 21.0.0.0 (21.1.1.109)
Since:  2016

Syntax

C#
public static NurbsSurfaceData Create(
	int degreeU,
	int degreeV,
	IList<double> knotsU,
	IList<double> knotsV,
	IList<XYZ> controlPoints,
	IList<double> weights,
	bool bReverseOrientation
)
Visual Basic
Public Shared Function Create ( _
	degreeU As Integer, _
	degreeV As Integer, _
	knotsU As IList(Of Double), _
	knotsV As IList(Of Double), _
	controlPoints As IList(Of XYZ), _
	weights As IList(Of Double), _
	bReverseOrientation As Boolean _
) As NurbsSurfaceData
Visual C++
public:
static NurbsSurfaceData^ Create(
	int degreeU, 
	int degreeV, 
	IList<double>^ knotsU, 
	IList<double>^ knotsV, 
	IList<XYZ^>^ controlPoints, 
	IList<double>^ weights, 
	bool bReverseOrientation
)

Parameters

degreeU
Type: System..::..Int32
The degree of the spline in the u-direction; must be positive.
degreeV
Type: System..::..Int32
The degree of the spline in the v-direction; must be positive.
knotsU
Type: System.Collections.Generic..::..IList<(Of <(<'Double>)>)>
Knot values in the u-direction. The number of knots in the u-direction must be at least 2 * (degreeU + 1).
knotsV
Type: System.Collections.Generic..::..IList<(Of <(<'Double>)>)>
Knot values in the v-direction. The number of knots in the v-direction must be at least 2 * (degreeV + 1).
controlPoints
Type: System.Collections.Generic..::..IList<(Of <(<'XYZ>)>)>
One dimensional array of points representing the two dimensional net of control points of the NURBS surface in u and v directions.

The total number of control points must equal numControlPtsU times numControlPtsV, where numControlPtsU and numControlPtsV are the numbers of control points in u and v directions, and they must satisfy the following conditions:

  • numControlPtsU = number of knots in u - degreeU - 1.
  • numControlPtsV = number of knots in v - degreeV - 1.
The convention for 2d (idxU, idxV) to 1d (idx) conversion of array indexes: idxV first. That is, idxU is outer loop and idxV is inner loop. In other words, idx = idxU * numControlPtsV + idxV.

weights
Type: System.Collections.Generic..::..IList<(Of <(<'Double>)>)>
Array of weights assigned to the control points. The number of weights must equal the number of control points. All weights should be greater than zero.
bReverseOrientation
Type: System..::..Boolean
If true, the surface's orientation is opposite to the canonical parametric orientation, otherwise it is the same. The canonical parametric orientation is a counter-clockwise sense of rotation in the uv-parameter plane. Extrinsically, the oriented normal vector for the canonical parametric orientation points in the direction of the cross product dS/du x dS/dv, which S(u, v) is the parameterized surface.

Exceptions

ExceptionCondition
Autodesk.Revit.Exceptions..::..ArgumentException The U-degree value must be at least 1. -or- The V-degree value must be at least 1. -or- The number of knots in the U direction must be at least 2 times the U-degree plus 1. -or- The number of knots in the V direction must be at least 2 times the V-degree plus 1. -or- The number of control points must equal (number of U-knots - U-degree - 1) * (number of V-knots - V-degree - 1). -or- The number of weights must be the same as the number of control points and all weights must be positive or all zero.
Autodesk.Revit.Exceptions..::..ArgumentNullException A non-optional argument was NULL

See Also