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ISketchSplineByEqnParams Method (IModelDoc2)

Creates a spline on the active 2D sketch using the specified b-curve parameters.

.NET Syntax

Visual Basic (Declaration) 
Function ISketchSplineByEqnParams( _
   ByRef PropArray As System.Integer, _
   ByRef KnotsArray As System.Double, _
   ByRef CntrlPntCoordArray As System.Double _
) As System.Integer
Visual Basic (Usage) 
Dim instance As IModelDoc2
Dim PropArray As System.Integer
Dim KnotsArray As System.Double
Dim CntrlPntCoordArray As System.Double
Dim value As System.Integer
value = instance.ISketchSplineByEqnParams(PropArray, KnotsArray, CntrlPntCoordArray)
System.int ISketchSplineByEqnParams( 
   ref System.int PropArray,
   ref System.double KnotsArray,
   ref System.double CntrlPntCoordArray
System.int ISketchSplineByEqnParams( 
&   System.int% PropArray,
&   System.double% KnotsArray,
&   System.double% CntrlPntCoordArray



Includes dimension, order, number of control points, and periodicity


knot1, knot2, and so on


controlpoint1[dimension], controlpoint2[dimension], and so on

Return Value

True if created successfully, false if not



The PropArray argument contains 4 integers packed into the first two doubles in the array:

  •  Dimension

  •  Order

  •  Number of Control Points

  •  Periodicity ( True or false )

The KnotsArray argument is an array of doubles with (Number of Control Points + Order) elements.

The size of the CntrlPntCoordArray array is based upon the curve dimension:

  • Dimension = 2 then each control point is an array of 2 doubles ( x, y )

  • Dimension = 3 then each control point is an array of 3 doubles ( x, y, z)

  • Dimension = 4 then each control point is an array of 4 doubles ( x, y, z, w ) where w = weight

The parameters are provided as 3 arrays, which for COM applications are passed separately.

Pass control point coordinates  to this method in sketch space. The Z value is interpreted as 0. In certain situations, you must transform your b-curve parameters to sketch space with the help of ISketch::ModelToSketchTransform.

NOTE: If the spline being generated is a closed spline, then it must be flagged as periodic. In addition, splines generated in sketches must be G1 continuous. If the data passed to this method does not generate a G1 continuous spline, then it is rejected and a spline is not created.


See Also


SOLIDWORKS 2001Plus FCS, Revision Number 10.0

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