IfcBuildingElementProxy

Definition from IAI: The IfcBuildingElementProxy is a proxy definition that provides the same functionality, as an IfcBuildingElement, but without having a defined meaning of the special type of building element, it represents.

NOTE The building element proxy should be used to exchange special types of building elements, for which the current IFC Release does not yet provide a semantic definition.

HISTORY: New entity in IFC Release 2.x.

Geometry Use Definitions

The geometric representation of any IfcBuildingElementProxy is given by the IfcProductDefinitionShape and IfcLocalPlacement allowing multiple geometric representations. The representation types defined at the supertype IfcBuildingElement also apply.

Local Placement

The local placement for any IfcBuildingElementProxy is defined in its supertype IfcProduct. It is defined by the IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations. The local placement can be given relativly.

Geometric Representation

Currently, the use of 'GeometricCurveSet', 'SurfaceModel', 'SweptSolid', 'Brep' representations is supported. In addition the general representation types 'BoundingBox' and 'MappedRepresentation' are allowed.

GeometricSet Representation

Any building element proxy may be represented by a geometric set, given by a collection of 2D points, curves and surfaces. It is ensured by assigning the value 'GeometricSet' to the RepresentationType attribute of IfcShapeRepresentation The RepresentationIdentifier of IfcShapeRepresentation should then have the value 'FootPrint'.

SurfaceModel Representation

Any building element proxy may be represented by a surface model. The surface model representation allows for the representation of complex element shape without defining a volume. It is ensured by assigning the value 'SurfaceModel' to the RepresentationType attribute of IfcShapeRepresentation The RepresentationIdentifier of IfcShapeRepresentation should then have the value 'Body'.

Swept Solid Representation

Any building element proxy may be represented by a swept area solid (either by extrusion or by revolution). The attribute RepresentationType of IfcShapeRepresentation should have the value 'SweptSolid' and the RepresentationIdentifier of IfcShapeRepresentation should then have the value 'Body'. No further restrictions (e.g., for the profile or extrusion direction) are defined at this level.

Brep Representation

The general b-rep geometric representation of IfcBuildingElementProxy is defined using the Brep geometry. The Brep representation allows for the representation of complex element shape. It is ensured by assigning the value 'Brep' to the RepresentationType attribute of IfcShapeRepresentation The RepresentationIdentifier of IfcShapeRepresentation should then have the value 'Body'.

EXPRESS specification:

ENTITY IfcBuildingElementProxy

SUBTYPE OF (

IfcBuildingElement);

CompositionType

OPTIONAL IfcElementCompositionEnum;

WHERE

WR1

EXISTS(SELF\IfcRoot.Name);

END_ENTITY;

Attribute definitions:

CompositionType

Indication, whether the proxy is intended to form an aggregation (COMPLEX), an integral element (ELEMENT), or a part in an aggregation (PARTIAL).

Formal Propositions:

WR1

A Name attribute should be asserted for a building element proxy.

Inheritance graph

ENTITY IfcBuildingElementProxy;

ENTITY IfcRoot;

GlobalId

IfcGloballyUniqueId;

OwnerHistory

IfcOwnerHistory;

Name

OPTIONAL IfcLabel;

Description

OPTIONAL IfcText;

ENTITY IfcObjectDefinition;

INVERSE

HasAssignments

SET OF IfcRelAssigns FOR RelatedObjects;

IsDecomposedBy

SET OF IfcRelDecomposes FOR RelatingObject;

Decomposes

SET [0:1] OF IfcRelDecomposes FOR RelatedObjects;

HasAssociations

SET OF IfcRelAssociates FOR RelatedObjects;

ENTITY IfcObject;

ObjectType

OPTIONAL IfcLabel;

INVERSE

IsDefinedBy

SET OF IfcRelDefines FOR RelatedObjects;

ENTITY IfcProduct;

ObjectPlacement

OPTIONAL IfcObjectPlacement;

Representation

OPTIONAL IfcProductRepresentation;

INVERSE

ReferencedBy

SET OF IfcRelAssignsToProduct FOR RelatingProduct;

ENTITY IfcElement;

Tag

OPTIONAL IfcIdentifier;

INVERSE

FillsVoids

SET [0:1] OF IfcRelFillsElement FOR RelatedBuildingElement;

ConnectedTo

SET OF IfcRelConnectsElements FOR RelatingElement;

HasCoverings

SET OF IfcRelCoversBldgElements FOR RelatingBuildingElement;

HasProjections

SET OF IfcRelProjectsElement FOR RelatingElement;

HasStructuralMember

SET OF IfcRelConnectsStructuralElement FOR RelatingElement;

ReferencedInStructures

SET OF IfcRelReferencedInSpatialStructure FOR RelatedElements;

HasPorts

SET OF IfcRelConnectsPortToElement FOR RelatedElement;

HasOpenings

SET OF IfcRelVoidsElement FOR RelatingBuildingElement;

IsConnectionRealization

SET OF IfcRelConnectsWithRealizingElements FOR RealizingElements;

ProvidesBoundaries

SET OF IfcRelSpaceBoundary FOR RelatedBuildingElement;

ConnectedFrom

SET OF IfcRelConnectsElements FOR RelatedElement;

ContainedInStructure

SET [0:1] OF IfcRelContainedInSpatialStructure FOR RelatedElements;

ENTITY IfcBuildingElement;

ENTITY IfcBuildingElementProxy;

CompositionType

OPTIONAL IfcElementCompositionEnum;

END_ENTITY;