8.9.3.64 IfcSineSpiral

8.9.3.64.1 Semantic definition

A type of spiral curve for which the curvature change is dependent on the sine function. It is also known as the Klein curve.

The curvature is defined as:

K = K0 (s LinearTerm - 1/2&pi sin2&pi/SineTerm)

8.9.3.64.2 Entity inheritance

8.9.3.64.3 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.
IfcSpiral (1)
1	Position	IfcAxis2Placement	No description available.
Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes
IfcSineSpiral (3)
2	SineTerm	IfcLengthMeasure	No description available.
3	LinearTerm	OPTIONAL IfcLengthMeasure	No description available.
4	ConstantTerm	OPTIONAL IfcLengthMeasure	No description available.

Table 8.9.3.64.A

8.9.3.64.4 Formal representation

ENTITY IfcSineSpiral
 SUBTYPE OF (IfcSpiral);
	SineTerm : IfcLengthMeasure;
	LinearTerm : OPTIONAL IfcLengthMeasure;
	ConstantTerm : OPTIONAL IfcLengthMeasure;
END_ENTITY;

8.9.3.64.5 References

IfcSpiral