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.
|LayerAssignment||SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems||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.|
> IFC2x3 CHANGE The inverse attribute LayerAssignments has been added.
> IFC4 CHANGE The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.
|StyledByItem||SET [0:1] OF IfcStyledItem FOR Item||Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve.|
> IFC2x3 CHANGE The inverse attribute StyledByItem has been added.
|1||Elements||SET [1:?] OF IfcGeometricSetSelect||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.|
|Dim||INVALID||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.|
ENTITY IfcGeometricSet SUPERTYPE OF (ONEOF (IfcGeometricCurveSet)) SUBTYPE OF (IfcGeometricRepresentationItem); Elements : SET [1:?] OF IfcGeometricSetSelect; DERIVE Dim : IfcDimensionCount := Elements.Dim; WHERE ConsistentDim : SIZEOF(QUERY(Temp <* Elements | Temp.Dim <> Elements.Dim)) = 0; END_ENTITY;