IfcReparametrisedCompositeCurveSegment

Semantic definitions at the entity

Entity definition

The IfcReparametrisedCompositeCurveSegment is geometrically identical to a IfcCompositeCurveSegment but with the additional capability of reparametrization.

NOTE Definition according to ISO/CD 10303-42:1992
The reparametrised composite curve segment is a special type of composite curve segment which provides the capability to re-define its parametric length without changing its geometry.

Let l = ParamLength.
If t₀ ≤ t ≤ t₁ is the parameter range of ParentCurve, the new parameter . for the reparametrised composite curve segment is given by the equation:
if SameSense = TRUE;
or by the equation:
if SameSense = FALSE;

NOTE Entity adapted from reparametrised_composite_curve_segment in ISO 10303-42.

HISTORY New entity in IFC4

Attribute definitions

#	Attribute	Type	Cardinality	Description	C
4	ParamLength	IfcParameterValue	[1:1]		X

Formal Propositions

Rule	Description
PositiveLengthParameter	The ParamLength shall be greater than zero.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	C
IfcRepresentationItem
	LayerAssignment	IfcPresentationLayerAssignment @AssignedItems	S[0:1]	Assignment of the representation item to a single or multiple layer(s). The LayerAssignments can override a LayerAssignments of the IfcRepresentation it is used within the list of Items.	X
	StyledByItem	IfcStyledItem @Item	S[0:1]	Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve.	X
IfcGeometricRepresentationItem
IfcCompositeCurveSegment
1	Transition	IfcTransitionCode	[1:1]	The state of transition (i.e., geometric continuity from the last point of this segment to the first point of the next segment) in a composite curve.	X
2	SameSense	IfcBoolean	[1:1]	An indicator of whether or not the sense of the segment agrees with, or opposes, that of the parent curve. If SameSense is false, the point with highest parameter value is taken as the first point of the segment. NOTE If the datatype of ParentCurve is IfcTrimmedCurve, the value of SameSense overrides the value of IfcTrimmedCurve.SenseAgreement	X
3	ParentCurve	IfcCurve	[1:1]	The bounded curve which defines the geometry of the segment.	X
	UsingCurves	IfcCompositeCurve @Segments	S[1:?]	The set of composite curves which use this composite curve segment as a segment. This set shall not be empty.	X
	Dim :=ParentCurve.Dim	IfcDimensionCount	[1:1]	The space dimensionality of this class, defined by the dimensionality of the first ParentCurve.	X
IfcReparametrisedCompositeCurveSegment
4	ParamLength	IfcParameterValue	[1:1]		X

Formal representations

XSD Specification

 <xs:element name="IfcReparametrisedCompositeCurveSegment" type="ifc:IfcReparametrisedCompositeCurveSegment" substitutionGroup="ifc:IfcCompositeCurveSegment" nillable="true"/>

 <xs:complexType name="IfcReparametrisedCompositeCurveSegment">

  <xs:complexContent>

   <xs:extension base="ifc:IfcCompositeCurveSegment">

    <xs:attribute name="ParamLength" type="ifc:IfcParameterValue" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcReparametrisedCompositeCurveSegment

 SUBTYPE OF (IfcCompositeCurveSegment);

  ParamLength : IfcParameterValue;

 WHERE

  PositiveLengthParameter : ParamLength > 0.0;
END_ENTITY;

 EXPRESS-G diagram

Item	Change	Description
IFC2x3 to IFC4
IfcReparametrisedCompositeCurveSegment	ADDED
IFC4 Addendum 1
IfcReparametrisedCompositeCurveSegment
SameSense	MODIFIED	Type changed from BOOLEAN to IfcBoolean.

	Reparametrisiertes Segment einer zusammengesetzten Kurve
	Reparametrised Composite Curve Segment