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ICreateBsplineSurface Method (IModeler)

Creates a b-spline surface.

.NET Syntax

Visual Basic (Declaration) 
Function ICreateBsplineSurface( _
   ByRef Properties As System.Integer, _
   ByRef UKnotArray As System.Double, _
   ByRef VKnotArray As System.Double, _
   ByRef ControlPointCoordArray As System.Double _
) As Surface
Visual Basic (Usage) 
Dim instance As IModeler
Dim Properties As System.Integer
Dim UKnotArray As System.Double
Dim VKnotArray As System.Double
Dim ControlPointCoordArray As System.Double
Dim value As Surface
value = instance.ICreateBsplineSurface(Properties, UKnotArray, VKnotArray, ControlPointCoordArray)
Surface ICreateBsplineSurface( 
   ref System.int Properties,
   ref System.double UKnotArray,
   ref System.double VKnotArray,
   ref System.double ControlPointCoordArray
Surface^ ICreateBsplineSurface( 
&   System.int% Properties,
&   System.double% UKnotArray,
&   System.double% VKnotArray,
&   System.double% ControlPointCoordArray


Array of 8 integers (see Remarks)
Array of numUKnots (see Remarks)
Array of numVKnots (see Remarks)
Array of numCtrlPtCoord (see Remarks)

Return Value



Number of elements in this array...

Given by...


numUKnots = numU_CtrlPoints + Uorder


numVKnots = numV_CtrlPoints + Vorder


numCtrlPtCoord =( NumV_CtrlPoints * NumU_CtrlPoints * DimensionControlPoints )

NOTE: The order of the UV control points are reversed if you used ISurface::GetBSurfParams3 or ISurface::IGetBSurfParams to get the data. You do not need to reverse the UV control points; instead, you can switch the UV knots and related parameters.

For periodics, the first knot must have multiplicity = 1 and all excess multiplicity must be imposed on the last knot. Therefore, a valid periodic knot vector would be { 0, 1, 2, 3, 3, 3 } for a cubic curve. The control point on the seam of the closed curve cannot be replicated at both ends; it should occur only at the beginning.

To convert from a clamped periodic curve (numKnots = numCtrlPts + Order, ctrlPts replicated, knot multiplicity = order at each end) to a SolidWorks periodic curve, remove all but one of the knots at the beginning of the vector and remove one at the end. Also remove the last control point to avoid the point replication.


See Also

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