Definition from buildingSMART: A special element used to provide imaginary boundaries, such as between two adjacent, but not separated, spaces. Virtual elements are usually not displayed and does not have quantities and other measures. Therefore IfcVirtualElement does not have material information and quantities attached.
NOTE The main purpose of IfcVirtualElement is the provision of a virtual space boundary. The IfcVirtualElement provides the 2D curve or 3D surface representation of the virtual space connection and is referenced by two instances of IfcRelSpaceBoundary, each pointing to one of the two adjacent IfcSpaces.
HISTORY New entity in IFC Release 2x2 Addendum 1.
IFC2x2 ADDENDUM CHANGE: The entity IfcVirtualElement has been added. Upward compatibility for file based exchange is guaranteed.
Geometry Use Definitions
The geometric representation of any IfcVirtualElement is given by the IfcProductDefinitionShape and IfcLocalPlacement allowing multiple geometric representations.
The local placement for IfcVirtualElement is defined in its supertype IfcProduct. It is defined by the IfcLocalPlacement, which defines the local coordinate system that is referenced by all geometric representations.
Currently, the use of 'FootPrint' and 'Surface' representation is supported.
Two-dimensional Representation using foot print representation
The 2D geometric representation of IfcVirtualElement is defined using the 'FootPring' or 'Surface' representation. The following attribute values should be inserted
The following constraints apply to the 2D curve representation:
Three-dimensional Representation using surface model representation
The 3D geometric representation of IfcVirtualElement is defined using the 'SurfaceModel' geometry. The following attribute values should be inserted
The following constraints apply to the 3D surface representation: