8.9.3.42 IfcOffsetCurveByDistances
8.9.3.42.1 Semantic definition
An IfcOffsetCurveByDistances is a curve defined by a list of offsets along its BasisCurve. If only one offset is provided, it indicates a constant offset along the extents of the basis curve.
Figure 8.9.3.42.A illustrates eight instances of IfcOffsetCurveByDistances (in green) defined relative to an IfcGradientCurve (in blue).
8.9.3.42.2 Entity inheritance
-
- IfcCurve
- IfcAnnotationFillArea
- IfcBooleanResult
- IfcBoundingBox
- IfcCartesianPointList
- IfcCartesianTransformationOperator
- IfcCsgPrimitive3D
- IfcDirection
- IfcFaceBasedSurfaceModel
- IfcFillAreaStyleHatching
- IfcFillAreaStyleTiles
- IfcGeometricSet
- IfcHalfSpaceSolid
- IfcLightSource
- IfcPlacement
- IfcPlanarExtent
- IfcPoint
- IfcSectionedSpine
- IfcSegment
- IfcShellBasedSurfaceModel
- IfcSolidModel
- IfcSurface
- IfcTessellatedItem
- IfcTextLiteral
- IfcVector
8.9.3.42.3 Attributes
| # | Attribute | Type | Description |
|---|---|---|---|
| IfcRepresentationItem (2) | |||
| LayerAssignment | SET [0:1] OF IfcPresentationLayerAssignment FOR AssignedItems |
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. |
|
| StyledByItem | SET [0:1] OF IfcStyledItem FOR Item |
Reference to the IfcStyledItem that provides presentation information to the representation, e.g. a curve style, including colour and thickness to a geometric curve. |
|
| IfcCurve (1) | |||
| * | Dim | IfcDimensionCount |
This attribute is formally derived. The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve. |
| IfcOffsetCurve (1) | |||
| 1 | BasisCurve | IfcCurve |
The curve that is being offset. |
| Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes | |||
| IfcOffsetCurveByDistances (2) | |||
| 2 | OffsetValues | LIST [1:?] OF IfcPointByDistanceExpression |
List of sequential points described relative to the basis curve. If the offsets do not span the full extent of the basis curve (e.g. if the list contains only one item), then the lateral and vertical offsets implicitly continue with the same value towards the head and tail of the basis curve. |
| 3 | Tag | OPTIONAL IfcLabel |
Optional identifier of the curve, which may be used to correlate points from a variable cross-section. |
8.9.3.42.4 Formal representation
ENTITY IfcOffsetCurveByDistances
SUBTYPE OF (IfcOffsetCurve);
OffsetValues : LIST [1:?] OF IfcPointByDistanceExpression;
Tag : OPTIONAL IfcLabel;
END_ENTITY;