5.1.3.19 IfcProxy

Objet utilisateur (définit par l'utilisateur)
beliebiges Objekt

IfcProxy is intended to be a kind of a container for wrapping objects which are defined by associated properties, which may or may not have a geometric representation and placement in space. A proxy may have a semantic meaning, defined by the Name attribute, and property definitions, attached through the property assignment relationship, which definition may be outside of the definitions given by the current release of IFC.

The ProxyType may give an indication to which high level semantic breakdown of object the semantic definition of the proxy relates to. the Tag attribute may be used to assign a human or system interpretable identifier (such as a serial number or bar code).

NOTE  Given that only a limited number of semantic constructs can be formally defined within IFC (and it will never be possible to define all), there has to be a mechanism for capturing those constructs that are not (yet) defined by IFC.
NOTE  Product proxies are a mechanism that allows to exchange data that is part of the project but not necessarily part of the IFC model. Those proxies may have geometric representations assigned.
HISTORY  New entity in IFC1.5.
DEPRECATION  The entity is deprecated and shall not be used.

XSD Specification:

 <xs:element name="IfcProxy" type="ifc:IfcProxy" substitutionGroup="ifc:IfcProduct" nillable="true"/>
 <xs:complexType name="IfcProxy">
  <xs:complexContent>
   <xs:extension base="ifc:IfcProduct">
    <xs:attribute name="ProxyType" type="ifc:IfcObjectTypeEnum" use="optional"/>
    <xs:attribute name="Tag" type="ifc:IfcLabel" use="optional"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>

EXPRESS Specification:

ENTITY IfcProxy
SUBTYPE OF IfcProduct;
ProxyType : IfcObjectTypeEnum;
Tag : OPTIONAL IfcLabel;
WHERE
WR1 : EXISTS(SELF\IfcRoot.Name);
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

ProxyType : High level (and only) semantic meaning attached to the IfcProxy, defining the basic construct type behind the Proxy, e.g. Product or Process.
Tag : The tag (or label) identifier at the particular instance of a product, e.g. the serial number, or the position number. It is the identifier at the occurrence level.

Formal Propositions:

WR1 : The Name attribute has to be provided for a proxy.

Inheritance Graph:

ENTITY IfcProxy
ENTITY IfcRoot
GlobalId : IfcGloballyUniqueId;
OwnerHistory : OPTIONAL IfcOwnerHistory;
Name : OPTIONAL IfcLabel;
Description : OPTIONAL IfcText;
ENTITY IfcObjectDefinition
INVERSE
HasAssignments : SET OF IfcRelAssigns FOR RelatedObjects;
Nests : SET [0:1] OF IfcRelNests FOR RelatedObjects;
IsNestedBy : SET OF IfcRelNests FOR RelatingObject;
HasContext : SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions;
IsDecomposedBy : SET OF IfcRelAggregates FOR RelatingObject;
Decomposes : SET [0:1] OF IfcRelAggregates FOR RelatedObjects;
HasAssociations : SET OF IfcRelAssociates FOR RelatedObjects;
ENTITY IfcObject
ObjectType : OPTIONAL IfcLabel;
INVERSE
IsDeclaredBy : SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects;
Declares : SET OF IfcRelDefinesByObject FOR RelatingObject;
IsTypedBy : SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects;
IsDefinedBy : SET OF IfcRelDefinesByProperties FOR RelatedObjects;
ENTITY IfcProduct
ObjectPlacement : OPTIONAL IfcObjectPlacement;
Representation : OPTIONAL IfcProductRepresentation;
INVERSE
ReferencedBy : SET OF IfcRelAssignsToProduct FOR RelatingProduct;
ENTITY IfcProxy
ProxyType : IfcObjectTypeEnum;
Tag : OPTIONAL IfcLabel;
END_ENTITY;

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