IfcPolyline

Semantic definitions at the entity

Entity definition

Definition from ISO/CD 10303-42:1992: An IfcPolyline is a bounded curve of n -1 linear segments, defined by a list of n points, P1, P2 ... Pn. The curve is parameterized as follows:

for 1 £ i £ n - 1, where i -1 £ u £ i and with parametric range of 0 £ u £ n - 1.

NOTE Corresponding STEP entity: polyline. Please refer to ISO/IS 10303-42:1994, p. 45 for the final definition of the formal standard.

HISTORY New class in IFC Release 1.0

Attribute definitions

#	Attribute	Type	Cardinality	Description	A
1	Points	IfcCartesianPoint	L[2:?]	The points defining the polyline.	X

Formal Propositions

Rule	Description
WR41	The space dimensionality of all Points shall be the same.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	A
IfcRepresentationItem
IfcGeometricRepresentationItem
IfcCurve
	Dim :=IfcCurveDim(SELF)	IfcDimensionCount	[1:1]	The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve.	X
IfcBoundedCurve
IfcPolyline
1	Points	IfcCartesianPoint	L[2:?]	The points defining the polyline.	X

Formal representations

XSD Specification

 <xs:element name="IfcPolyline" type="ifc:IfcPolyline" substitutionGroup="ifc:IfcBoundedCurve" nillable="true"/>

 <xs:complexType name="IfcPolyline">

  <xs:complexContent>

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

    <xs:sequence>

     <xs:element name="Points">

      <xs:complexType>

       <xs:sequence>

        <xs:element ref="ifc:IfcCartesianPoint" minOccurs="2" maxOccurs="unbounded"/>

       </xs:sequence>

       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcCartesianPoint"/>

       <xs:attribute ref="ifc:cType" fixed="list"/>

       <xs:attribute ref="ifc:arraySize" use="optional"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPolyline

 SUBTYPE OF (IfcBoundedCurve);

  Points : LIST [2:?] OF IfcCartesianPoint;

 WHERE

  WR41 : SIZEOF(QUERY(Temp <* Points | Temp.Dim <> Points[1].Dim)) = 0;
END_ENTITY;

 EXPRESS-G diagram