8.9.3.25 IfcCurve

RV ⓘ

AbV ⓘ

ABSTRACT This definition may not be instantiated

8.9.3.25.1 Semantic definition

An IfcCurve is a curve in two-dimensional or three-dimensional space. It includes definitions for bounded and unbounded curves.

Informal Propositions

A curve shall be arcwise connected
A curve shall have an arc length greater than zero.

8.9.3.25.2 Entity inheritance

8.9.3.25.3 Attributes

#	Attribute	Type	Description
IfcRepresentationItem (2)
	LayerAssignment	SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems	Assignment of the representation item to a single or multiple layer(s). The LayerAssignments can override a LayerAssignments of the IfcRepresentation it is used within the list of Items. IFC2x3-CHANGE The inverse attribute LayerAssignments has been added. IFC4-CHANGE The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.
	StyledByItem	SET [0:1] OF IfcStyledItem FOR Item	Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve. IFC2x3-CHANGE The inverse attribute StyledByItem has been added.
Click to show 2 hidden inherited attributes
IfcCurve (1)
*	Dim	IfcDimensionCount	This attribute is formally derived. `IfcCurveDim(SELF)` The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve.

Table 8.9.3.25.A

8.9.3.25.4 Formal representation

 ENTITY IfcCurve
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcBoundedCurve
	,IfcConic
	,IfcLine
	,IfcOffsetCurve
	,IfcPcurve
	,IfcPolynomialCurve
	,IfcSpiral
	,IfcSurfaceCurve))
 SUBTYPE OF (IfcGeometricRepresentationItem);
 DERIVE
	 Dim : IfcDimensionCount := IfcCurveDim(SELF);
END_ENTITY;