Function AddTrimmingLoop2( _
   ByVal NCrvs As System.Integer, _
   ByVal VOrder As System.Object, _
   ByVal VDim As System.Object, _
   ByVal VPeriodic As System.Object, _
   ByVal VNumKnots As System.Object, _
   ByVal VNumCtrlPoints As System.Object, _
   ByVal VKnots As System.Object, _
   ByVal VCtrlPointDbls As System.Object, _
   ByVal UvRange As System.Object _
) As System.Boolean

Dim instance As ISurface
Dim NCrvs As System.Integer
Dim VOrder As System.Object
Dim VDim As System.Object
Dim VPeriodic As System.Object
Dim VNumKnots As System.Object
Dim VNumCtrlPoints As System.Object
Dim VKnots As System.Object
Dim VCtrlPointDbls As System.Object
Dim UvRange As System.Object
Dim value As System.Boolean
 
value = instance.AddTrimmingLoop2(NCrvs, VOrder, VDim, VPeriodic, VNumKnots, VNumCtrlPoints, VKnots, VCtrlPointDbls, UvRange)

System.bool AddTrimmingLoop2( 
   System.int NCrvs,
   System.object VOrder,
   System.object VDim,
   System.object VPeriodic,
   System.object VNumKnots,
   System.object VNumCtrlPoints,
   System.object VKnots,
   System.object VCtrlPointDbls,
   System.object UvRange
)

System.bool AddTrimmingLoop2( 
&   System.int NCrvs,
&   System.Object^ VOrder,
&   System.Object^ VDim,
&   System.Object^ VPeriodic,
&   System.Object^ VNumKnots,
&   System.Object^ VNumCtrlPoints,
&   System.Object^ VKnots,
&   System.Object^ VCtrlPointDbls,
&   System.Object^ UvRange
) 

Parameters

NCrvs

Number of surface parametric (UV) curves constituting the loop and the size of each of the VOrder, VDim, VPeriodic, VNumKnots, VNumControlPnts arrays

VOrder

Array containing NCrvs longs (VBA), Integers (VB.NET), or ints (C#, C++) representing orders of the curves (see Remarks)

VDim

Array containing NCrvs longs (VBA), Integers (VB.NET), or ints (C#, C++) representing dimensions (2, 3, or 4) of the control points of the curves (see Remarks)

VPeriodic

Array containing NCrvs longs (VBA), Integers (VB.NET), or ints (C#, C++) representing whether the curve is periodic (1) or non-periodic (0) (see Remarks)

VNumKnots

Array containing NCrvs longs (VBA), Integers (VB.NET), or ints (C#, C++) representing number of knots on the curves (see Remarks)

VNumCtrlPoints

Array containing NCrvs longs (VBA), Integers (VB.NET), or ints (C#, C++) representing number of control points on the curves (see Remarks)

VKnots

Knot vector array of <TotalNumKnots> doubles, where TotalNumKnots = (TotalNumKnots + VNumKnots[i]) for i = 1 to NCrvs (see Remarks)

VCtrlPointDbls

Control point coordinate array of <TotalNumCPCoords> doubles, where TotalNumCPCoords = (TotalNumCPCoords + (VDim[i] * VNumCtrlPoints[i])) for i = 1 to NCrvs (see Remarks)

UvRange

Array of four doubles representing U Low, U High, V Low, and V High (see Remarks)

Return Value

The list of trimming loops is created by a previous call to one of the base surface creation functions, IBody2::CreateRevolutionSurface or IBody2::CreatePlanarSurface.

The information on each UV-curve is in b-spline form (knots and control point coordinates) and is compacted into two arrays, VKnots and VCtrlPointDbls.

Order of each curve in VOrder is, at a minimum, 2. A second order curve is a linear curve.

For each curve in VNumCtrlPoints, VOrder, and VNumKnots, (NumCtrlPoints >= Order) and (NumKnots = NumCtrlPoints + Order).

Dim for each curve in VDim specifies the dimension of each CtrlPointDbl set in VCtrlPointDbls. This method expects 2D-polynomial (X,Y) or 2D-rational (X,Y,Weight) curves to be passed as trimming curves. However, you can set a flag so that this method accepts 3D-polynomial (X,Y,Z) or 3D-rational (X,Y,Z,Weight) trim curves. To do this, negate the absolute value of the first value in the VDim array. For example, if the first VDim value is 3, set it to -3. When you do this, 3D trim curves are expected.

If Dim is:

• 2, specify (X,Y) control points in each CtrlPointDbl set.
• -2, specify (X,Y,Z) control points in each CtrlPointDbl set. 
• 3, specify (X,Y,Weight) control points in each CtrlPointDbl.
• -3, specify (X,Y,Z,Weight) control points in each CtrlPointDbl.

Multiplicity of a knot is the number of times it is repeated in the knot vector. There are specific rules around number of knots, knot multiplicity, and curve order. For example, if a curve's Periodic value is:

• 0 (non-periodic), there must be (NumCtrlPoints + Order) knots and the maximum multiplicity of any knot is Order.
• 1 (periodic), there must be (NumCtrlPoints + 1) knots and the maximum multiplicity of any knot is Order. If a knot has multiplicity greater than 1, repetitions must occur at the end of the knot vector.

If you do not want to specify a UV range, use null or Nothing in the UvRange array elements.

After calling this method to add a trimming loop, you can generate the trimmed surface by calling IBody2::CreateTrimmedSurface. You can create a body from trimmed surfaces using IBody2::CreateBodyFromSurfaces.

NOTE: It is highly recommended that you consult other resources for the mathematics behind b-splines, knots, knot multiplicity, and control points before attempting to use this method.