Ifc2DCompositeCurve

Ifc2DCompositeCurve

Definition from IAI: An Ifc2DCompositeCurve is an IfcCompositeCurve that is defined within the coordinate space of an IfcPlane. Therefore the dimensionality of the Ifc2DCompositeCurve has to be 2.

NOTE OF DEPRECATION: After the enhancement of the profile definition capacities in IFC Release 2.x this entity is not needed anymore for the definition of boundaries on a plane. Therefore this entity is marked as deprecated - that means it will not be supported in future versions of IFC.

NOTE: This entity has been introduced to get a more straight forward definition of surface boundaries than by its counterpart in STEP: composite_curve_on_surface and boundary_curve. Since the only basis elementary surface in IFC is the plane surface, a two dimensional composite curve provides enough capability to define the boundary.

HISTORY: New class in IFC Release 1.5

EXPRESS specification:

ENTITY Ifc2DCompositeCurve

SUBTYPE OF (

IfcCompositeCurve);

WHERE

WR1	:	SELF\IfcCompositeCurve.ClosedCurve;
WR2	:	SELF\IfcCurve.Dim = 2;

END_ENTITY;

Formal Propositions:

WR1	:	The composite curve shall be closed.
WR2	:	The dimensionality of the composite curve shall be 2

Inheritance graph

ENTITY Ifc2DCompositeCurve;

ENTITY IfcRepresentationItem;

ENTITY IfcGeometricRepresentationItem;

ENTITY IfcCurve;

DERIVE

Dim

IfcDimensionCount := IfcCurveDim(SELF);

ENTITY IfcBoundedCurve;

ENTITY IfcCompositeCurve;

Segments

LIST [1:?] OF IfcCompositeCurveSegment;

SelfIntersect

LOGICAL;

DERIVE

NSegments

INTEGER := SIZEOF(Segments);

ClosedCurve

LOGICAL := Segments[NSegments].Transition <> Discontinuous;

ENTITY Ifc2DCompositeCurve;

END_ENTITY;