IfcPointOnSurface

Semantic definitions at the entity

Entity definition

The IfcPointOnSurface is a point defined by two parameter value of its defining surface.

NOTE Definition according to ISO/CD 10303-42:1992
A point on surface is a point which lies on a parametric surface. The point is determined by evaluating the surface at a particular pair of parameter values.

NOTE Entity adapted from point_on_surface in ISO 10303-42.

HISTORY New entity in IFC2x2.

Informal Propositions:

The parametric values specified for u and v shall not be outside the parametric range of the basis surface.

Attribute definitions

#	Attribute	Type	Description	G
1	BasisSurface	IfcSurface	The surface to which the parameter values relate.	X
2	PointParameterU	IfcParameterValue	The first parameter value of the point location.	X
3	PointParameterV	IfcParameterValue	The second parameter value of the point location.	X
	Dim :=BasisSurface.Dim	IfcDimensionCount	The space dimensionality of this class, determined by the space dimensionality of the basis surface.	X

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
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. IFC2x3 CHANGE The inverse attribute LayerAssignments has been added. IFC4 CHANGE The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.	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. IFC2x3 CHANGE The inverse attribute StyledByItem has been added.	X
IfcGeometricRepresentationItem
IfcPoint
IfcPointOnSurface
1	BasisSurface	IfcSurface		The surface to which the parameter values relate.	X
2	PointParameterU	IfcParameterValue		The first parameter value of the point location.	X
3	PointParameterV	IfcParameterValue		The second parameter value of the point location.	X
	Dim :=BasisSurface.Dim	IfcDimensionCount		The space dimensionality of this class, determined by the space dimensionality of the basis surface.	X

Formal representations

XML Specification

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

 <xs:complexType name="IfcPointOnSurface">

  <xs:complexContent>

   <xs:extension base="ifc:IfcPoint">

    <xs:sequence>

     <xs:element name="BasisSurface" type="ifc:IfcSurface" nillable="true"/>

    </xs:sequence>

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

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

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPointOnSurface

 SUBTYPE OF (IfcPoint);

  BasisSurface : IfcSurface;

  PointParameterU : IfcParameterValue;

  PointParameterV : IfcParameterValue;

 DERIVE

  Dim : IfcDimensionCount := BasisSurface.Dim;

END_ENTITY;

 EXPRESS-G diagram

	Punkt auf einer Oberfläche
	Point On Surface
	Point de surface