IfcAnnotation

Definition from IAI: An annotation is a graphical representation within the geometric (and spatial) context of a project, that adds a note or meaning to the objects which constitutes the project model. Annotations include additional line drawings, text, dimensioning, hatching and other forms of graphical notes.

NOTE Additional presentation information (often 2D) such as tag number, hatching, etc., that is directly related to a particular product representation is included within the IfcProductDefinitionShape having various IfcShapeRepresentation's of the IfcElement (and its subtypes). Only those presentation information, that cannot be directly related to a single product, have to be wrapped within the IfcAnnotation.

If available, the annotation should be related to the spatial context of the project, by containing the annotation within the appropriate level of the building structure (site, building, storey, or space). This is handled by the IfcRelContainedInSpatialStructure relationship.

HISTORY: New entity in Release IFC2x Edition 2.

Geometry Use Definitions

The geometric representation of any IfcAnnotation is given by the IfcProductDefinitionShape and IfcLocalPlacement allowing multiple geometric representations.

Local Placement

The local placement for any IfcAnnotation 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.

• The PlacementRelTo relationship of IfcLocalPlacement shall point (if given) to the local placement of the same IfcSpatialStructureElement, which is used in the ContainedInStructure inverse attribute, or to a spatial structure element at a higher level, referenced by that.
• If the relative placement is not used, the absolute placement is defined within the world coordinate system.

Geometric Representations

The standard representation of IfcAnnotation is defined using 'GeometricCurveSet' or, when including surfaces, the 'GeometricSet' geometry. Styled items adding the style information assigned to the geometric representation items are grouped together with the geometric representation items within the set of Items at IfcShapeRepresentation.

EXPRESS specification:

Attribute definitions:

Inheritance graph