Class Ifc4::IfcOffsetCurve3D¶
Defined in File Ifc4.h
Nested Relationships¶
This class is a nested type of Struct Ifc4.
Inheritance Relationships¶
Base Type¶
public Ifc4::IfcCurve
(Class Ifc4::IfcCurve)
Class Documentation¶

class
Ifc4
::
IfcOffsetCurve3D
: public Ifc4::IfcCurve¶ Definition from ISO/CD 1030342:1992: An offset curve 3d is a curve at a constant distance from a basis curve in threedimensional space. The underlying curve shall have a welldefined tangent direction at every point. In the case of a composite curve the transition code between each segment shall be cont same gradient or cont same gradient same curvature. The offset curve at any point (parameter) on the basis curve is in the direction V x T where V is the fixed reference direction and T is the unit tangent to the basis curve. For the offset direction to be well defined, T shall not at any point of the curve be in the same, or opposite, direction as V.
NOTE: The offset curve 3d may differ in nature from the basis curve; the offset of a non self intersecting curve can be selfintersecting. Care should be taken to ensure that the offset to a continuous curve does not become discontinuous.
The offset curve 3d takes its parameterization from the basis curve. The offset curve 3d is parameterized as
where T is the unit tangent vector to the basis curve C(u) at parameter value u, and d is distance. The underlying curve shall be threedimensional.
NOTE Corresponding ISO 10303 entity: offset_curve_3d, Please refer to ISO/IS 1030342:1994, p.66 for the final definition of the formal standard.
HISTORY New entity in IFC Release 2.x
Informal propositions:
At no point on the curve shall ref direction be parallel, or opposite to, the direction of the tangent vector.
Public Types

typedef IfcTemplatedEntityList<IfcOffsetCurve3D>
list
¶
Public Functions

double
Distance
() const¶ The distance of the offset curve from the basis curve. The distance may be positive, negative or zero.

void
setDistance
(double v)¶

bool
SelfIntersect
() const¶ An indication of whether the offset curve selfintersects, this is for information only.

void
setSelfIntersect
(bool v)¶

::Ifc4::IfcDirection *
RefDirection
() const¶ The direction used to define the direction of the offset curve 3d from the basis curve.

void
setRefDirection
(::Ifc4::IfcDirection *v)¶

IfcOffsetCurve3D
(IfcEntityInstanceData *e)¶

IfcOffsetCurve3D
(::Ifc4::IfcCurve *v1_BasisCurve, double v2_Distance, bool v3_SelfIntersect, ::Ifc4::IfcDirection *v4_RefDirection)¶

typedef IfcTemplatedEntityList<IfcOffsetCurve3D>