Natural language names
Semantic definitions at the entity
Entity definition

The IfcPolyline is a bounded curve with only linear segments defined by a list of Cartesian points. If the first and the last Cartesian point in the list are identical, then the polyline is a closed curve, otherwise it is an open curve.

EXAMPLE  Figure 346 illustrates a bounded IfcPolyline and shows the parametric length of each segment and of the total polyline.
polyline examples

Figure 346 — Bounded IfcPolyline with parametric length

NOTE  Definition according to ISO/CD 10303-42:1992
A polyline is a bounded curve of n - 1 linear segments, defined by a list of n points, P1, P2 ... Pn. The ith segment of the curve is parameterized as follows:
    for 1 ≤ in - 1
where i - 1 ≤ ui and with parametric range of 0 <≤ un - 1.
NOTE  Entity adapted from polyline in ISO 10303-42.
HISTORY  New entity in IFC1.0
Attribute definitions
#AttributeTypeCardinalityDescription C
1PointsIfcCartesianPointL[2:?] The points defining the polyline.X
Formal Propositions
SameDimThe space dimensionality of all Points shall be the same.
Inherited definitions from supertypes
Entity inheritance IfcBoundedCurve IfcCurve IfcGeometricRepresentationItem IfcRepresentationItem
Attribute inheritance
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
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
IfcDimensionCount[1:1]The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve. X
1PointsIfcCartesianPointL[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:extension base="ifc:IfcBoundedCurve">
     <xs:element name="Points">
        <xs:element ref="ifc:IfcCartesianPoint" minOccurs="2" maxOccurs="unbounded"/>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcCartesianPoint"/>
       <xs:attribute ref="ifc:cType" fixed="list"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
EXPRESS Specification
ENTITY IfcPolyline
 SUBTYPE OF (IfcBoundedCurve);
  Points : LIST [2:?] OF IfcCartesianPoint;
  SameDim : SIZEOF(QUERY(Temp <* Points | Temp.Dim <> Points[1].Dim)) = 0;

Link to EXPRESS-G diagram EXPRESS-G diagram

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