IfcProduct

Semantic definitions at the entity

Entity definition

Any object, or any aid to define, organize and annotate an object, that relates to a geometric or spatial context. Subtypes of IfcProduct usually hold a shape representation and a local placement within the project structure.

This includes manufactured, supplied or created objects (referred to as elements) for incorporation into an AEC/FM project. This also includes objects that are created indirectly by other products, as spaces are defined by bounding elements. Products can be designated for permanent use or temporary use, an example for the latter is formwork. Products are defined by their properties and representations.

In addition to physical products (covered by the subtype IfcElement) and spatial items (covered by the subtype IfcSpatialStructureElement) the IfcProduct also includes non-physical items, that relate to a geometric or spatial contexts, such as grid, port, annotation, structural actions, etc.

HISTORY New Entity in IFC Release 1.0

Use Definition

Any instance of IfcProduct defines a particular occurrence of a product, the common type information, that relates to many similar (or identical) occurrences of IfcProduct, is handled by the IfcTypeProduct (and its subtypes), assigned to one or many occurrences of IfcProduct by using the objectified relationship IfcRelDefinesByType. The IfcTypeProduct may provide, in addition to common properties, also a common geometric representation for all occurrences.

An IfcProduct occurs at a specific location in space if it has a geometric representation assigned. It can be placed relatively to other products, but ultimately relative to the world coordinate system defined for this project.

The inherited ObjectType attribute can be used to designate a particular type of the product instance. If subtypes of IfcProduct have a PredefinedType defined, the ObjectType is used to provide the user defined, particular type of the product instance, if the PredefinedType is set to USERDEFINED.

Attribute definitions

#	Attribute	Type	Cardinality	Description	A
6	ObjectPlacement	IfcObjectPlacement	[0:1]	Placement of the product in space, the placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system.	X
7	Representation	IfcProductRepresentation	[0:1]	Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement.	X

Formal Propositions

Rule	Description
WR1	If an Representation is given, then also a LocalPlacement has to be given.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	A
IfcRoot
1	GlobalId	IfcGloballyUniqueId	[1:1]	Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	IfcOwnerHistory	[1:1]	Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object, NOTE: only the last modification in stored.	X
3	Name	IfcLabel	[0:1]	Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule.	X
4	Description	IfcText	[0:1]	Optional description, provided for exchanging informative comments.	X
IfcObjectDefinition
	IsDecomposedBy	IfcRelDecomposes @RelatingObject	S[0:?]	Reference to the decomposition relationship, that allows this object to be the composition of other objects. An object can be decomposed by several other objects.	X
	Decomposes	IfcRelDecomposes @RelatedObjects	S[0:1]	References to the decomposition relationship, that allows this object to be a part of the decomposition. An object can only be part of a single decomposition (to allow hierarchical strutures only).	X
	HasAssociations	IfcRelAssociates @RelatedObjects	S[0:?]	Reference to the relationship objects, that associates external references or other resource definitions to the object.. Examples are the association to library, documentation or classification.	X
IfcObject
5	ObjectType	IfcLabel	[0:1]	The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute PredefinedType is set to USERDEFINED.	X
	IsDefinedBy	IfcRelDefines @RelatedObjects	S[0:?]	Set of relationships to type or property (statically or dynamically defined) information that further define the object. In case of type information, the associated IfcTypeObject contains the specific information (or type, or style), that is common to all instances of IfcObject referring to the same type.	X
IfcProduct
6	ObjectPlacement	IfcObjectPlacement	[0:1]	Placement of the product in space, the placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system.	X
7	Representation	IfcProductRepresentation	[0:1]	Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement.	X

Formal representations

XSD Specification

 <xs:element name="IfcProduct" type="ifc:IfcProduct" abstract="true" substitutionGroup="ifc:IfcObject" nillable="true"/>

 <xs:complexType name="IfcProduct" abstract="true">

  <xs:complexContent>

   <xs:extension base="ifc:IfcObject">

    <xs:sequence>

     <xs:element name="ObjectPlacement" type="ifc:IfcObjectPlacement" nillable="true" minOccurs="0"/>

     <xs:element name="Representation" type="ifc:IfcProductRepresentation" nillable="true" minOccurs="0"/>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcProduct

 ABSTRACT SUPERTYPE OF(ONEOF(IfcElement, IfcGrid, IfcSpatialStructureElement))

 SUBTYPE OF (IfcObject);

  ObjectPlacement : OPTIONAL IfcObjectPlacement;

  Representation : OPTIONAL IfcProductRepresentation;

 INVERSE

 WHERE

  WR1 : (EXISTS(Representation) AND EXISTS(ObjectPlacement))
            OR (EXISTS(Representation) AND 
               (NOT('IFCREPRESENTATIONRESOURCE.IFCPRODUCTDEFINITIONSHAPE' IN TYPEOF(Representation))))
            OR (NOT(EXISTS(Representation)))
;
END_ENTITY;

 EXPRESS-G diagram