8.9.3.40 IfcOffsetCurve2D

8.9.3.40.1 Semantic definition

An IfcOffsetCurve2D is a curve defined by an offset in 2D space from its BasisCurve.

8.9.3.40.2 Entity inheritance

8.9.3.40.3 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.
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.
IfcOffsetCurve (1)
1	BasisCurve	IfcCurve	The curve that is being offset.
Click to show 4 hidden inherited attributes
IfcOffsetCurve2D (2)
2	Distance	IfcLengthMeasure	The distance of the offset curve from the basis curve. distance may be positive, negative or zero. A positive value of distance defines an offset in the direction which is normal to the curve in the sense of an anti-clockwise rotation through 90 degrees from the tangent vector T at the given point. (This is in the direction of orthogonal complement(T).)
3	SelfIntersect	IfcLogical	An indication of whether the offset curve self-intersects; this is for information only.

Table 8.9.3.40.B

8.9.3.40.4 Formal propositions

Name	Description
DimIs2D	The underlying curve shall be defined in two-dimensional space.
`BasisCurve.Dim = 2`

Table 8.9.3.40.C

8.9.3.40.5 Formal representation

 ENTITY IfcOffsetCurve2D
 SUBTYPE OF (IfcOffsetCurve);
	Distance : IfcLengthMeasure;
	SelfIntersect : IfcLogical;
 WHERE
	DimIs2D : BasisCurve.Dim = 2;
END_ENTITY;

8.9.3.40 IfcOffsetCurve2D

8.9.3.40.1 Semantic definition

8.9.3.40.2 Entity inheritance

8.9.3.40.3 Attributes

8.9.3.40.4 Formal propositions

8.9.3.40.5 Formal representation

8.9.3.40.6 Changelog

8.9.3.40.6.1 IFC4

8.9.3.40.6.2 IFC4.1

	ENTITY IfcOffsetCurve2D
	SUBTYPE OF (IfcOffsetCurve);
	Distance : IfcLengthMeasure;
	SelfIntersect : IfcLogical;
	WHERE
	DimIs2D : BasisCurve.Dim = 2;
	END_ENTITY;