IfcOuterBoundaryCurve定义有界曲面的外部边界。
注：定义根据ISO/CD 10303-42:1992
这是边界曲线的一个特殊子类型，它具有定义曲面外部边界的附加语义。曲线边界曲面的边界集中不得包含一条以上的曲线。
注：实体改编自ISO 10303-42中的外边界_曲线。
IFC4中增加的新实体。
| # | 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 | |||||
| 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 | |||||
| IfcCompositeCurve | |||||
| 1 | Segments | IfcCompositeCurveSegment | L[1:?] | The component bounded curves, their transitions and senses. The transition attribute for the last segment defines the transition between the end of the last segment and the start of the first; this transition attribute may take the value discontinuous, which indicates an open curve. | X |
| 2 | SelfIntersect | IfcLogical | [1:1] | Indication of whether the curve intersects itself or not; this is for information only. | X |
| NSegments :=SIZEOF(Segments) |
IfcInteger | [1:1] | The number of component curves. | X | |
| ClosedCurve :=Segments[NSegments].Transition <> Discontinuous |
IfcLogical | [1:1] | Indication whether the curve is closed or not; this is derived from the transition code of the last segment. | X | |
| IfcCompositeCurveOnSurface | |||||
| BasisSurface :=IfcGetBasisSurface(SELF) |
IfcSurface | S[0:1] | The surface on which the composite curve is defined. | X | |
| IfcBoundaryCurve | |||||
| IfcOuterBoundaryCurve | |||||
EXPRESS Specification
ENTITY IfcOuterBoundaryCurve
SUBTYPE OF (IfcBoundaryCurve);
END_ENTITY;