CIP Visual Basic.NET documentation for interface "IpfcGeomCurve"

Interface IpfcGeomCurve

Description

This class provides information for a geometry curve or edge.

Direct Parent Classes:: IpfcObject

Direct Known Subclasses:: IpfcEdge, IpfcCurve

Property Summary


`Property`	`IsVisible`	`as Boolean`
	true if the geometry is visible and active, false if it is invisible and inactive. Inactive geometry may not have all geometric properties defined.

Method Summary


`Function`	`Eval3DData (Param as Double) as IpfcCurveXYZData`
	Returns a `IpfcCurveXYZData` object with information on the point represented by input parameter t.

`Function`	`EvalFromLength (StartParameter as Double, Length as Double) as IpfcCurveXYZData`
	Returns a CURVEXYZData object with information on the point that is a specified distance from the starting point as specified by input parameter t.

`Function`	`EvalLength () as Double`
	Finds the length of the specified edge.

`Function`	`EvalLengthBetween (Param1 as Double, Param2 as Double) as Double`
	Finds the length of the specified curve between two given parameters.

`Function`	`EvalParameter (Point as IpfcPoint3D) as Double`
	Finds the corresponding normalized parameter on the curve, given the XYZ point.

`Function`	`GetCurveDescriptor () as IpfcCurveDescriptor`
	This method returns a data object containing the geometry of the edge or curve.

`Function`	`GetFeature () as IpfcFeature`
	Returns the feature which contains the geometry.

`Function`	`GetNURBSRepresentation () as IpfcBSplineDescriptor`
	This method returns the geometry of the edge or curve as a non-uniform rational B-spline curve.

Property Detail

Property IsVisible as Boolean

true if the geometry is visible and active, false if it is invisible and inactive. Inactive geometry may not have all geometric properties defined.

Method Detail

Function Eval3DData (Param as Double) as IpfcCurveXYZData

Returns a IpfcCurveXYZData object with information on the point represented by input parameter t.

If the curve is a composite curve,first derivative IpfcCurveXYZData.Derivative1 and second derivative IpfcCurveXYZData.Derivative2 are not accessible and will benull.

Exceptions thrown (but not limited to):

IpfcXToolkitNotImplemented - The argument p_curve represents a composite curve, while deriv1 or deriv2 is not NULL.

Parameters:

Param: The t parameter on the edge.

Returns:: The evaluation data, including the resulting point, the first and second derivatives, and the normal to the surface

Function EvalFromLength (StartParameter as Double, Length as Double) as IpfcCurveXYZData

Returns a CURVEXYZData object with information on the point that is a specified distance from the starting point as specified by input parameter t.

Exceptions thrown (but not limited to):

IpfcXToolkitBadSrfCrv - The input argument is invalid.

Parameters:

StartParameter: The starting t parameter
Length: The distance from the starting parameter t to the resulting point

Returns:: The point at the specified distance from the starting parameter

Function EvalLength () as Double

Finds the length of the specified edge.

Returns:: The edge length

Function EvalLengthBetween (Param1 as Double, Param2 as Double) as Double

Finds the length of the specified curve between two given parameters.

Exceptions thrown (but not limited to):

IpfcXToolkitBadSrfCrv - The input argument is invalid.

Parameters:

Param1: The start t parameter
Param2: The end t parameter

Returns:: The curve length between the parameters.

Function EvalParameter (Point as IpfcPoint3D) as Double

Finds the corresponding normalized parameter on the curve, given the XYZ point.

Parameters:

Point: The XYZ point. The point does not need to lie on the curve.If the point is not on the curve, the function finds the closest curve point.

Returns:: The t parameter that represents the input Point3D object.

Function GetCurveDescriptor () as IpfcCurveDescriptor

This method returns a data object containing the geometry of the edge or curve.

Exceptions thrown (but not limited to):

IpfcXToolkitInvalidType - The specified data is not a composite curve data structure.

Returns:: The edge or curve geometry

Function GetFeature () as IpfcFeature

Returns the feature which contains the geometry.

Returns:: The feature.

Function GetNURBSRepresentation () as IpfcBSplineDescriptor

This method returns the geometry of the edge or curve as a non-uniform rational B-spline curve.

Returns:: The B-spline curve geometry