IfcRepresentation
Definition from ISO/CD 10303-43:1992: A
representation is one
or more representation items that are related in a specified
representation context as the representation of some concept.
Definition from IAI: The IfcRepresentation
defines
the general concept of representing product properties.
NOTE
The definition of
this entity relates to the STEP entity representation. Please refer to
ISO/IS 10303-43:1994 for the final definition of the formal standard.
HISTORY
New entity in IFC
Release 2.0
IFC2x Edition 3 NOTE
Users should not instantiate the
entity IfcRepresentation from IFC2x Edition 3
onwards. It will be changed into an ABSTRACT supertype in future
releases of IFC.
IFC2x Edition 3 CHANGE The inverse attributes LayerAssignments
and
RepresentationMap have been added with upward
compatibility.
EXPRESS specification:
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| RepresentationIdentifier
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OPTIONAL IfcLabel;
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Attribute definitions:
| ContextOfItems
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Definition of the representation context for which the different subtypes of representation are valid.
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| RepresentationIdentifier
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The optional identifier of the representation as used within a project.
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| RepresentationType
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The description of the type of a representation context. The representation type defines the type of geometry or topology used for representing the product representation. More information is given at the subtypes IfcShapeRepresentation and IfcTopologyRepresentation.
The supported values for context type are to be specified by implementers agreements.
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| Items
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Set of geometric representation items that are defined for this representation.
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| RepresentationMap
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Use of the representation within an IfcRepresentationMap. If used, this IfcRepresentation may be assigned to many representations as one of its Items using an IfcMappedItem. Using IfcRepresentationMap is the way to share one representation (often of type IfcShapeRepresentation) by many products.
IFC2x Edition 3 CHANGE The inverse attribute LayerAssignments has been added.
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| LayerAssignments
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Assignment of the whole representation to a single or multiple layer(s). The LayerAssigments can be overridden by LayerAssigments of the IfcRepresentationItem's within the list of Items.
NOTE Implementation agreements can restrict the maximum number of layer assignments to 1.
IFC2x Edition 3 CHANGE The inverse attribute LayerAssignments has been added.
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| OfProductRepresentation
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Reference to the product shape, for which it is the shape representation.
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Inheritance graph
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| ENTITY IfcRepresentation;
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| RepresentationIdentifier
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OPTIONAL IfcLabel;
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