IfcGeometricCurveSet

IfcGeometricCurveSet用于交换仅由（2D或3D）点和曲线集合组成的形状表示。

注：定义根据ISO/CD 10303-42:1992

几何曲线集是二维或三维点和曲线的集合。

注：实体改编自ISO 10303-42中定义的几何曲线集。

IFC2x2中增加的新实体。

Formal Propositions

Rule	Description
NoSurfaces	No surface shall be included in this geometric set.

 

#	Attribute	Type	Cardinality	Description	C
IfcRepresentationItem
	LayerAssignment	IfcPresentationLayerAssignment @AssignedItems	S[0:1]	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.	X
	StyledByItem	IfcStyledItem @Item	S[0:1]	Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve.	X
IfcGeometricRepresentationItem
IfcGeometricSet
1	Elements	IfcGeometricSetSelect	S[1:?]	The geometric elements which make up the geometric set, these may be points, curves or surfaces; but are required to be of the same coordinate space dimensionality.	X
	Dim :=Elements[1].Dim	IfcDimensionCount	[1:1]	The space dimensionality of this class, it is identical to the first element in the set. A where rule ensures that all elements have the same dimensionality.	X
IfcGeometricCurveSet

EXPRESS Specification

ENTITY IfcGeometricCurveSet
 SUBTYPE OF (IfcGeometricSet);
 WHERE
  NoSurfaces : SIZEOF(QUERY(Temp <* SELFIfcGeometricSet.Elements | 'IFCGEOMETRYRESOURCE.IFCSURFACE' IN TYPEOF(Temp))) = 0;
END_ENTITY;