#### 8.7.3.8 IfcCompositeCurveSegment

| Segment de courbe composite
| Segment einer zusammengesetzten Kurve

An IfcCompositeCurveSegment is a bounded curve constructed for the sole purpose to be a segment within an IfcCompositeCurve.

> NOTE Definition according to ISO/CD 10303-42:1992
> A composite curve segment is a bounded curve together with transition information which is used to construct a composite curve.

> NOTE Entity adapted from composite_curve_segment defined in ISO 10303-42.

> HISTORY New entity in IFC1.0

XSD Specification:

<xs:element name="IfcCompositeCurveSegment" type="ifc:IfcCompositeCurveSegment" substitutionGroup="ifc:IfcGeometricRepresentationItem" nillable="true"/>
<xs:complexType name="IfcCompositeCurveSegment">
<xs:complexContent>
<xs:extension base="ifc:IfcGeometricRepresentationItem">
<xs:sequence>
<xs:element name="ParentCurve" type="ifc:IfcCurve" nillable="true"/>
</xs:sequence>
<xs:attribute name="Transition" type="ifc:IfcTransitionCode" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>

EXPRESS Specification:

ENTITY IfcCompositeCurveSegment

| SUBTYPE OF (IfcGeometricRepresentationItem);

Transition | : | IfcTransitionCode;
SameSense | : | IfcStrippedOptional;
ParentCurve | : | IfcCurve;

| INVERSE

UsingCurves | : | SET [1:?] OF IfcCompositeCurve FOR Segments;

| DERIVE

Dim | : | IfcDimensionCount := ParentCurve.Dim;

| WHERE

ParentIsBoundedCurve | : | ('IFCGEOMETRYRESOURCE.IFCBOUNDEDCURVE' IN TYPEOF(ParentCurve));

END_ENTITY;

Attribute Definitions:

Transition | : | The state of transition (i.e., geometric continuity from the last point of this segment to the first point of the next segment) in a composite curve.
SameSense | : | An indicator of whether or not the sense of the segment agrees with, or opposes, that of the parent curve. If SameSense is false, the point with highest parameter value is taken as the first point of the segment. NOTE If the datatype of ParentCurve is IfcTrimmedCurve, the value of SameSense overrides the value of IfcTrimmedCurve.SenseAgreement
ParentCurve | : | The bounded curve which defines the geometry of the segment.
Dim | : | The space dimensionality of this class, defined by the dimensionality of the first ParentCurve.
UsingCurves | : | The set of composite curves which use this composite curve segment as a segment. This set shall not be empty.

Formal Propositions:

ParentIsBoundedCurve | : | The parent curve shall be a bounded curve.

Inheritance Graph:

ENTITY IfcCompositeCurveSegment

| ENTITY IfcRepresentationItem

| INVERSE

LayerAssignment | : | SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems;
StyledByItem | : | SET [0:1] OF IfcStyledItem FOR Item;

| ENTITY IfcGeometricRepresentationItem

| ENTITY IfcCompositeCurveSegment

Transition | : | IfcTransitionCode;
SameSense | : | IfcStrippedOptional;
ParentCurve | : | IfcCurve;

| INVERSE

UsingCurves | : | SET [1:?] OF IfcCompositeCurve FOR Segments;

| DERIVE

Dim | : | IfcDimensionCount := ParentCurve.Dim;

END_ENTITY;

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