|modifications||attributes RelatingStructure definition||Changed from IfcSpatialStructureElement to IfcSpatialElement|
|modifications||attributes RelatedElements definition||Changed from set[1:?] of IfcProduct to set[1:?] of IfcSpatialReferenceSelect|
The objectified relationship, IfcRelReferencedInSpatialStructure is used to assign elements in addition to those levels of the project spatial structure, in which they are referenced, but not primarily contained. It is also used to connect a system to the relevant spatial element that it serves.
NOTE The primary containment relationship between an element and the spatial structure is handled by IfcRelContainedInSpatialStructure.
Any element can be referenced to zero, one or several levels of the spatial structure. Whereas the IfcRelContainedInSpatialStructure relationship is required to be hierarchical (an element can only be contained in exactly one spatial structure element), the IfcRelReferencedInSpatialStructure is not restricted to be hierarchical.
EXAMPLE A wall might be normally contained within a storey, and since it does not span through several stories, it is not referenced in any additional storey. However a curtain wall might span through several stories, in this case it can be contained within the ground floor, but it would be referenced by all additional stories, it spans.
Predefined spatial structure elements to which elements can be assigned are
Elements can also be references in a spatial zone that is provided as IfcSpatialZone.
Figure 1 shows the use of IfcRelContainedInSpatialStructure and IfcRelReferencedInSpatialStructure to assign an IfcCurtainWall to two different levels within the spatial structure. It is primarily contained within the ground floor, and additionally referenced within the first and second floor.
HISTORY New entity in IFC2x3.
|1||GlobalId||IfcGloballyUniqueId||Assignment of a globally unique identifier within the entire software world.|
|2||OwnerHistory||OPTIONAL IfcOwnerHistory||Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object, |
> NOTE only the last modification in stored - either as addition, deletion or modification.
> IFC4 CHANGE The attribute has been changed to be OPTIONAL.
|3||Name||OPTIONAL IfcLabel||Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule.|
|4||Description||OPTIONAL IfcText||Optional description, provided for exchanging informative comments.|
|5||RelatedElements||SET [1:?] OF IfcSpatialReferenceSelect|
IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept.
Ownership, history, and merge state is captured using IfcOwnerHistory.
ENTITY IfcRelReferencedInSpatialStructure SUBTYPE OF (IfcRelConnects); RelatedElements : SET [1:?] OF IfcSpatialReferenceSelect; RelatingStructure : IfcSpatialElement; WHERE AllowedRelatedElements : SIZEOF(QUERY(temp <* RelatedElements | ('IFC4X3_DEV_a1492713.IFCSPATIALSTRUCTUREELEMENT' IN TYPEOF(temp)) AND (NOT ('IFC4X3_DEV_a1492713.IFCSPACE' IN TYPEOF(temp))) )) = 0; END_ENTITY;