IfcPointOnCurve

Semantic definitions at the entity

Entity definition

The IfcPointOnCurve is a point defined by a parameter value of its defining curve.

NOTE Definition according to ISO/CD 10303-42:1992
A point on curve is a point which lies on a curve. The point is determined by evaluating the curve at a specific parameter value. The coordinate space dimensionality of the point is that of the basis curve.

NOTE Entity adapted from point_on_curve in ISO 10303-42.

HISTORY New entity in IFC2x2.

Informal Propositions:

The value of the point parameter shall not be outside the parametric range of the curve.

Attribute definitions

#	Attribute	Type	Cardinality	Description	C
1	BasisCurve	IfcCurve	[1:1]	The curve to which point parameter relates.	X
2	PointParameter	IfcParameterValue	[1:1]	The parameter value of the point location.	X
	Dim :=BasisCurve.Dim	IfcDimensionCount	[1:1]	The space dimensionality of this class, determined by the space dimensionality of the basis curve.	X

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
IfcPoint
IfcPointOnCurve
1	BasisCurve	IfcCurve	[1:1]	The curve to which point parameter relates.	X
2	PointParameter	IfcParameterValue	[1:1]	The parameter value of the point location.	X
	Dim :=BasisCurve.Dim	IfcDimensionCount	[1:1]	The space dimensionality of this class, determined by the space dimensionality of the basis curve.	X

Formal representations

XSD Specification

 <xs:element name="IfcPointOnCurve" type="ifc:IfcPointOnCurve" substitutionGroup="ifc:IfcPoint" nillable="true"/>

 <xs:complexType name="IfcPointOnCurve">

  <xs:complexContent>

   <xs:extension base="ifc:IfcPoint">

    <xs:sequence>

     <xs:element name="BasisCurve" type="ifc:IfcCurve" nillable="true"/>

    </xs:sequence>

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

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPointOnCurve

 SUBTYPE OF (IfcPoint);

  BasisCurve : IfcCurve;

  PointParameter : IfcParameterValue;

 DERIVE

  Dim : IfcDimensionCount := BasisCurve.Dim;

END_ENTITY;

 EXPRESS-G diagram

	Punkt auf einer Kurve
	Point On Curve
	Point de courbe