IfcSurfaceOfLinearExtrusion

Semantic definitions at the entity

Entity definition

The IfcSurfaceOfLinearExtrusion is a surface derived by sweeping a curve along a vector.

NOTE Definition according to ISO/CD 10303-42:1992
This surface is a simple swept surface or a generalized cylinder obtained by sweeping a curve in a given direction. The parameterization is as follows where the curve has a parameterization λ(u):

V = ExtrusionAxis

The parameterization range for v is -∞ < v < ∞ and for u it is defined by the curve parameterization.

NOTE Entity adapted from surface_of_linear_extrusion defined in ISO 10303-42.

HISTORY New entity in IFC2x.

Informal Propositions:

The surface shall not self-intersect

Attribute definitions

#	Attribute	Type	Cardinality	Description	C
3	ExtrudedDirection	IfcDirection	[1:1]	The direction of the extrusion.	X
4	Depth	IfcLengthMeasure	[1:1]	The depth of the extrusion, it determines the parameterization.	X
	ExtrusionAxis :=IfcRepresentationItem() \|\| IfcGeometricRepresentationItem () \|\| IfcVector (ExtrudedDirection, Depth)	IfcVector	[1:1]	The extrusion axis defined as vector.	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
IfcSurface
	Dim :=3	IfcDimensionCount	[1:1]	The space dimensionality of IfcSurface. It is always a three-dimensional geometric representation item.	X
IfcSweptSurface
1	SweptCurve	IfcProfileDef	[1:1]	The curve to be swept in defining the surface. The curve is defined as a profile within the position coordinate system.	X
2	Position	IfcAxis2Placement3D	[0:1]	Position coordinate system for the swept surface, provided by a profile definition within the XY plane of the Position coordinates. If not provided, the position of the profile being swept is determined by the object coordinate system. In this case, the swept surface is not repositioned.	X
IfcSurfaceOfLinearExtrusion
3	ExtrudedDirection	IfcDirection	[1:1]	The direction of the extrusion.	X
4	Depth	IfcLengthMeasure	[1:1]	The depth of the extrusion, it determines the parameterization.	X
	ExtrusionAxis :=IfcRepresentationItem() \|\| IfcGeometricRepresentationItem () \|\| IfcVector (ExtrudedDirection, Depth)	IfcVector	[1:1]	The extrusion axis defined as vector.	X

Formal representations

XSD Specification

 <xs:element name="IfcSurfaceOfLinearExtrusion" type="ifc:IfcSurfaceOfLinearExtrusion" substitutionGroup="ifc:IfcSweptSurface" nillable="true"/>

 <xs:complexType name="IfcSurfaceOfLinearExtrusion">

  <xs:complexContent>

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

    <xs:sequence>

     <xs:element name="ExtrudedDirection" type="ifc:IfcDirection" nillable="true"/>

    </xs:sequence>

    <xs:attribute name="Depth" type="ifc:IfcLengthMeasure" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcSurfaceOfLinearExtrusion

 SUBTYPE OF (IfcSweptSurface);

  ExtrudedDirection : IfcDirection;

  Depth : IfcLengthMeasure;

 DERIVE

  ExtrusionAxis : IfcVector := IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector (ExtrudedDirection, Depth);

 WHERE

  DepthGreaterZero : Depth > 0.;
END_ENTITY;

 EXPRESS-G diagram

Item	Change	Description
IFC2x3 to IFC4
IfcSurfaceOfLinearExtrusion
Position	MODIFIED	Instantiation changed to OPTIONAL.

	Oberfläche - Entlang einem Vektor extrudiert
	Surface Of Linear Extrusion
	Extrusion linéaire ou surfacique