IfcTopologyRepresentation

Definition from IAI: The IfcTopologyRepresentation represents the concept of a particular topological representation of a product or a product component within a representation context. This representation context does not need to be (but may be) a geometric representation context. Several representation types for shape representation are included as predefined types:

Vertex	topological vertex representation (with or without assigned geometry)
Edge	topological edge representation (with or without assigned geometry)
Path	topological path representation (with or without assigned geometry)
Face	topological face representation (with or without assigned geometry)
Shell	topological shell representation (with or without assigned geometry)
Undefined	no constraints imposed

The representation type is given as a string value at the inherited attribute 'RepresentationType'.

HISTORY: New entity in Release IFC 2x Edition 2.

EXPRESS specification:

ENTITY IfcTopologyRepresentation

SUBTYPE OF (

IfcShapeModel);

WHERE

WR21	:	SIZEOF(QUERY(temp <* SELF\IfcRepresentation.Items \| NOT('IFCTOPOLOGYRESOURCE.IFCTOPOLOGICALREPRESENTATIONITEM' IN TYPEOF(temp)) )) = 0 ;
WR22	:	EXISTS(SELF\IfcRepresentation.RepresentationType);
WR23	:	IfcTopologyRepresentationTypes(SELF\IfcRepresentation.RepresentationType, SELF\IfcRepresentation.Items);

END_ENTITY;

Formal Propositions:

WR21	:	Only topological representation items should be used.
WR22	:	A representation type should be given to the topology representation.
WR23	:	Checks the proper use of Items according to the RepresentationType.

Inheritance graph

ENTITY IfcTopologyRepresentation;

ENTITY IfcRepresentation;

ContextOfItems

IfcRepresentationContext;

RepresentationIdentifier

OPTIONAL IfcLabel;

RepresentationType

OPTIONAL IfcLabel;

Items

SET [1:?] OF IfcRepresentationItem;

INVERSE

RepresentationMap

SET [0:1] OF IfcRepresentationMap FOR MappedRepresentation;

LayerAssignments

SET OF IfcPresentationLayerAssignment FOR Assigneditems;

OfProductRepresentation

SET [0:1] OF IfcProductRepresentation FOR Representations;

ENTITY IfcShapeModel;

INVERSE

OfShapeAspect

SET [0:1] OF IfcShapeAspect FOR ShapeRepresentations;

ENTITY IfcTopologyRepresentation;

END_ENTITY;