IfcSurfaceOfLinearExtrusion

Natural language names
Oberfläche - Entlang einem Vektor extrudiert
Surface Of Linear Extrusion
Extrusion linéaire ou surfacique
Change log
ItemSPFXMLChangeDescription
IFC2x3 to IFC4 4.0.0.0
    IfcSurfaceOfLinearExtrusion
      PositionMODIFIEDInstantiation changed to OPTIONAL.
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

Image 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:

  1. The surface shall not self-intersect
Attribute definitions
#AttributeTypeCardinalityDescription G
3ExtrudedDirectionIfcDirection The direction of the extrusion. X
4DepthIfcLengthMeasure The depth of the extrusion, it determines the parameterization. X
ExtrusionAxis
:=IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector (ExtrudedDirection, Depth)
IfcVectorThe extrusion axis defined as vector. X
Inherited definitions from supertypes
Entity inheritance IfcSweptSurface IfcSurface IfcGeometricRepresentationItem IfcRepresentationItem
Attribute inheritance
#AttributeTypeCardinalityDescriptionG
IfcRepresentationItem
LayerAssignmentIfcPresentationLayerAssignment
@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
StyledByItemIfcStyledItem
@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
IfcSurface
Dim
:=3
IfcDimensionCountThe space dimensionality of IfcSurface. It is always a three-dimensional geometric representation item.
IFC4 CHANGE Derived attribute promoted from subtypes.
X
IfcSweptSurface
1SweptCurveIfcProfileDef The curve to be swept in defining the surface. The curve is defined as a profile within the position coordinate system. X
2PositionIfcAxis2Placement3D? 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.
IFC4 CHANGE  The attribute has been changed to OPTIONAL with upward compatibility for file-based exchange.
X
IfcSurfaceOfLinearExtrusion
3ExtrudedDirectionIfcDirection The direction of the extrusion. X
4DepthIfcLengthMeasure The depth of the extrusion, it determines the parameterization. X
ExtrusionAxis
:=IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector (ExtrudedDirection, Depth)
IfcVectorThe extrusion axis defined as vector. X
Formal representations
XML 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;

Link to EXPRESS-G diagram EXPRESS-G diagram

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