IfcGeometricSet

Natural language names
deGeometrische Gruppe
enGeometric Set
Semantic definitions at the entity
Entity definition

The IfcGeometricSet is used for the exchange of shape representation consisting of (2D or 3D) points, curves, and surfaces, which do not have a topological structure (such as connected face sets or shells), are not tessellated and are not solid models (such as swept solids, CSG or Brep).

NOTE  Definition from ISO/CD 10303-42:
This entity is intended for the transfer of models when a topological structure is not available.
NOTE  Entity adapted from geometric_set defined in ISO 10303-42.
HISTORY  New entity in IFC2x.
Attribute definitions
#AttributeTypeCardinalityDescription C
1ElementsIfcGeometricSetSelectS[1:?] The geometric elements which make up the geometric set, these may be points, curves or surfaces; but are required to be of the same coordinate space dimensionality.X
Dim
:=Elements[1].Dim
IfcDimensionCount[1:1]The space dimensionality of this class, it is identical to the first element in the set. A where rule ensures that all elements have the same dimensionality. X
Formal Propositions
RuleDescription
ConsistentDimAll elements within a geometric set shall have the same dimensionality.
Inherited definitions from supertypes
Entity inheritance IfcGeometricCurveSet IfcGeometricRepresentationItem IfcRepresentationItem
Attribute inheritance
#AttributeTypeCardinalityDescriptionC
IfcRepresentationItem
LayerAssignmentIfcPresentationLayerAssignment
@AssignedItems
S[0:1]Assignment of the representation item to a single or multiple layer(s). The LayerAssignments can override a LayerAssignments of the IfcRepresentation it is used within the list of Items. X
StyledByItemIfcStyledItem
@Item
S[0:1]Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve. X
IfcGeometricRepresentationItem
IfcGeometricSet
1ElementsIfcGeometricSetSelectS[1:?] The geometric elements which make up the geometric set, these may be points, curves or surfaces; but are required to be of the same coordinate space dimensionality.X
Dim
:=Elements[1].Dim
IfcDimensionCount[1:1]The space dimensionality of this class, it is identical to the first element in the set. A where rule ensures that all elements have the same dimensionality. X
Formal representations
XSD Specification
 <xs:element name="IfcGeometricSet" type="ifc:IfcGeometricSet" substitutionGroup="ifc:IfcGeometricRepresentationItem" nillable="true"/>
 <xs:complexType name="IfcGeometricSet">
  <xs:complexContent>
   <xs:extension base="ifc:IfcGeometricRepresentationItem">
    <xs:sequence>
     <xs:element name="Elements">
      <xs:complexType>
       <xs:group ref="ifc:IfcGeometricSetSelect" maxOccurs="unbounded"/>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcGeometricSetSelect"/>
       <xs:attribute ref="ifc:cType" fixed="set"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
      </xs:complexType>
     </xs:element>
    </xs:sequence>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcGeometricSet
 SUPERTYPE OF(IfcGeometricCurveSet)
 SUBTYPE OF (IfcGeometricRepresentationItem);
  Elements : SET [1:?] OF IfcGeometricSetSelect;
 DERIVE
  Dim : IfcDimensionCount := Elements[1].Dim;
 WHERE
  ConsistentDim : SIZEOF(QUERY(Temp <* Elements | Temp.Dim <> Elements[1].Dim)) = 0;
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

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