IFC 4.3.x development

8.8.3.20 IfcGeometricCurveSet

Change log

IFC4

additionswhere_rulesNoSurfaces
deletionswhere_rulesWR1

IFC4X1

additionswhere_rulesNoSurfaces
deletionswhere_rulesNoSurfaces

IFC4X2

additionswhere_rulesNoSurfaces
deletionswhere_rulesNoSurfaces

IFC4X3_RC3

additionswhere_rulesNoSurfaces
deletionswhere_rulesNoSurfaces

8.8.3.20.1 Semantic definitions at the entity

The IfcGeometricCurveSet is used for the exchange of shape representation consisting of an collection of (2D or 3D) points and curves only.

NOTE  Definition according to ISO/CD 10303-42:1992
A geometric curve set is a collection of two or three dimensional points and curves.

NOTE  Entity adapted from geometric_curve_set defined in ISO 10303-42.

HISTORY  New entity in IFC2x2.

Formal Propositions

NoSurfaces

No surface shall be included in this geometric set.

# Attribute Type Description
IfcRepresentationItem
LayerAssignmentSET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItemsAssignment 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.
IfcGeometricRepresentationItem
IfcGeometricSet
1 Elements SET [1:?] OF IfcGeometricSetSelect 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.
Dim INVALID 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.

8.8.3.20.1 Entity inheritance

dot_inheritance IfcGeometricCurveSet IfcGeometricCurveSet IfcGeometricSet IfcGeometricSet IfcGeometricCurveSet->IfcGeometricSet IfcGeometricRepresentationItem IfcGeometricRepresentationItem IfcGeometricSet->IfcGeometricRepresentationItem IfcGeometricRepresentationItem_children 24 more... IfcGeometricRepresentationItem_children->IfcGeometricRepresentationItem IfcRepresentationItem IfcRepresentationItem IfcGeometricRepresentationItem->IfcRepresentationItem IfcRepresentationItem_children 3 more... IfcRepresentationItem_children->IfcRepresentationItem

8.8.3.20.2 Formal representations

ENTITY IfcGeometricCurveSet
 SUBTYPE OF (IfcGeometricSet);
 WHERE
	NoSurfaces : SIZEOF(QUERY(Temp <* SELF\IfcGeometricSet.Elements |
'IFC4X3_DEV_a1492713.IFCSURFACE' IN TYPEOF(Temp))) = 0;
END_ENTITY;