IFC 4.3.x development

5.1.3.45 IfcRoot

Change log

IFC4

modificationsattributes OwnerHistory is_optionalChanged from False to True

5.1.3.45.1 Semantic definitions at the entity

IfcRoot is the most abstract and root class for all entity definitions that roots in the kernel or in subsequent layers of the IFC specification. It is therefore the common supertype of all IFC entities, beside those defined in an IFC resource schema. All entities that are subtypes of IfcRoot can be used independently, whereas resource schema entities, that are not subtypes of IfcRoot, are not supposed to be independent entities.

NOTE  View definitions and implementation agreement may impose additional restrictions on the use of the OwnerHistory to handle object versioning.

HISTORY  New entity in IFC1.0

IFC4 CHANGE  The attribute OwnerHistory has been made OPTIONAL.

5.1.3.45.1 Attributes

#Attribute Type Description
IfcRoot
1GlobalId IfcGloballyUniqueId Assignment of a globally unique identifier within the entire software world.
2OwnerHistoryOPTIONAL IfcOwnerHistoryAssignment 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.
3Name 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.
4Description OPTIONAL IfcText Optional description, provided for exchanging informative comments.

5.1.3.45.2 Entity inheritance

dot_inheritance IfcObjectDefinition IfcObjectDefinition IfcRoot IfcRoot IfcObjectDefinition->IfcRoot IfcPropertyDefinition IfcPropertyDefinition IfcPropertyDefinition->IfcRoot IfcRelationship IfcRelationship IfcRelationship->IfcRoot

5.1.3.45.3 Definitions applying to General Usage

5.1.3.45.3.1 Identity

IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept.

5.1.3.45.3.2 Revision Control

Ownership, history, and merge state is captured using IfcOwnerHistory.

5.1.3.45.4 Formal representations

ENTITY IfcRoot
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcObjectDefinition
	,IfcPropertyDefinition
	,IfcRelationship));
	GlobalId : IfcGloballyUniqueId;
	OwnerHistory : OPTIONAL IfcOwnerHistory;
	Name : OPTIONAL IfcLabel;
	Description : OPTIONAL IfcText;
 UNIQUE
	UR1 : GlobalId;
END_ENTITY;