IFC 4.3.x development

8.15.3.16 IfcParameterizedProfileDef

Change log

IFC4

modificationsattributes Position is_optionalChanged from False to True

8.15.3.16.1 Semantic definitions at the entity

The parameterized profile definition defines a 2D position coordinate system to which the parameters of the different profiles relate to. All profiles are defined centric to the origin of the position coordinate system, or more specific, the origin [0.,0.] shall be in the center of the bounding box of the profile.

The Position attribute of IfcParameterizedProfileDef is used to position the profile within the XY plane of the underlying coordinate system of the swept surface geometry, the swept area solid or the sectioned spine. It can be used to position the profile at any point which becomes the origin [0.,0.,0.] of the extruded or rotated surface or solid.

The Position attribute should not be used if the transformation can be specified in a containing object instead. In particular, this applies if the IfcParameterizedProfileDef is referenced as SweptArea in subtypes of IfcSweptAreaSolid or as CrossSections in IfcSectionedSpine.

Several subtypes of IfcParameterizedProfileDef provide shape parameters which are optional. Sending systems should always provide values for these parameters if possible. If these parameters are left unspecified, receiving systems may retrieve values for them by external reference (if a reference to an external document or library is given; see guidance at IfcProfileDef), or estimate them, or simply assume zero values.

HISTORY  New entity in IFC2x2.

IFC2x CHANGE  The IfcParameterizedProfileDef is introduced as an intermediate new abstract entity that unifies the definition and usage of the position coordinate system for all parameterized profiles. The Position attribute has been removed at all subtypes (like IfcRectangleProfileDef, IfcCircleProfileDef, etc.).

IFC2x3 CHANGE  All profile origins are now in the center of the bounding box.

IFC4 CHANGE  Position attribute made optional (default: identity transformation).
Several radius parameters in subtypes have been changed from optional IfcPositiveLengthMeasure (assumed default: 0.) to optional IfcNonNegativeLengthMeasure (default: unspecified). This change allows to explicitly specify zero radius. Sending systems shall export 0. values if parameters are known to be 0.
Subtypes IfcCraneRailAShapeProfileDef and IfcCraneRailFShapeProfileDef deleted. Rail profiles shall be modeled as IfcArbitraryClosedProfileDef or as IfcAsymmetricIShapeProfileDef together with appropriate external reference.

8.15.3.16.1 Attributes

# Attribute Type Description
IfcProfileDef
1 ProfileType IfcProfileTypeEnum Defines the type of geometry into which this profile definition shall be resolved, either a curve or a surface area. In case of curve the profile should be referenced by a swept surface, in case of area the profile should be referenced by a swept area solid.
2 ProfileName OPTIONAL IfcLabel Human-readable name of the profile, for example according to a standard profile table. As noted above, machine-readable standardized profile designations should be provided in _IfcExternalReference.ItemReference_.
HasExternalReferenceSET [0:?] OF IfcExternalReferenceRelationship FOR RelatedResourceObjectsReference to external information, e.g. library, classification, or document information, which is associated with the profile.

> IFC4 CHANGE New inverse attribute
HasProperties SET [0:?] OF IfcProfileProperties FOR ProfileDefinition Additional properties of the profile, for example mechanical properties.

> IFC4 CHANGE New inverse attribute
IfcParameterizedProfileDef
3 Position OPTIONAL IfcAxis2Placement2D Position coordinate system of the parameterized profile definition. If unspecified, no translation and no rotation is applied.

8.15.3.16.2 Entity inheritance

dot_inheritance IfcParameterizedProfileDef_children 10 more... IfcParameterizedProfileDef IfcParameterizedProfileDef IfcParameterizedProfileDef_children->IfcParameterizedProfileDef IfcProfileDef IfcProfileDef IfcParameterizedProfileDef->IfcProfileDef IfcProfileDef_children 5 more... IfcProfileDef_children->IfcProfileDef

8.15.3.16.3 Definitions applying to General Usage

8.15.3.16.3.1 Property Sets for Objects

PsetName
'Pset_ProfileMechanical'

8.15.3.16.4 Formal representations

ENTITY IfcParameterizedProfileDef
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcAsymmetricIShapeProfileDef
	,IfcCShapeProfileDef
	,IfcCircleProfileDef
	,IfcEllipseProfileDef
	,IfcIShapeProfileDef
	,IfcLShapeProfileDef
	,IfcRectangleProfileDef
	,IfcTShapeProfileDef
	,IfcTrapeziumProfileDef
	,IfcUShapeProfileDef
	,IfcZShapeProfileDef))
 SUBTYPE OF (IfcProfileDef);
	Position : OPTIONAL IfcAxis2Placement2D;
END_ENTITY;