8.9.3.2 IfcAxis2Placement2D
8.9.3.2.1 Semantic definition
The IfcAxis2Placement2D provides location and orientation to place items in a two-dimensional space. The attribute RefDirection defines the x axis, the y axis is derived. If the attribute RefDirection is not given, the placement defaults to P[1] (x-axis) as [1.,0.] and P[2] (y-axis) as [0.,1.].
Figure 8.9.3.2.A illustrates the definition of the IfcAxis2Placement2D within the two-dimensional coordinate system.
8.9.3.2.2 Entity inheritance
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- IfcPlacement
- IfcAnnotationFillArea
- IfcBooleanResult
- IfcBoundingBox
- IfcCartesianPointList
- IfcCartesianTransformationOperator
- IfcCsgPrimitive3D
- IfcCurve
- IfcDirection
- IfcFaceBasedSurfaceModel
- IfcFillAreaStyleHatching
- IfcFillAreaStyleTiles
- IfcGeometricSet
- IfcHalfSpaceSolid
- IfcLightSource
- IfcPlanarExtent
- IfcPoint
- IfcSectionedSpine
- IfcSegment
- IfcShellBasedSurfaceModel
- IfcSolidModel
- IfcSurface
- IfcTessellatedItem
- IfcTextLiteral
- IfcVector
8.9.3.2.3 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. |
|
IfcPlacement (2) | |||
1 | Location | IfcPoint |
The geometric position of a reference point, such as the center of a circle, of the item to be located. |
* | Dim | IfcDimensionCount |
This attribute is formally derived.
The space dimensionality of this class, derived from the dimensionality of the location. |
Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes | |||
IfcAxis2Placement2D (2) | |||
2 | RefDirection | OPTIONAL IfcDirection |
The direction used to determine the direction of the local X axis. If a value is omitted that it defaults to [1.0, 0.0.]. |
* | P | LIST [2:2] OF IfcDirection |
This attribute is formally derived.
P[1]: The normalized direction of the placement X Axis. This is [1.0,0.0] if RefDirection is omitted. P[2]: The normalized direction of the placement Y Axis. This is a derived attribute and is orthogonal to P[1]. If RefDirection is omitted, it defaults to [0.0,1.0] |
8.9.3.2.4 Formal propositions
Name | Description |
---|---|
LocationIs2D |
No description available. |
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LocationIsCP |
No description available. |
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RefDirIs2D |
No description available. |
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8.9.3.2.5 Examples
8.9.3.2.6 Formal representation
ENTITY IfcAxis2Placement2D
SUBTYPE OF (IfcPlacement);
RefDirection : OPTIONAL IfcDirection;
DERIVE
P : LIST [2:2] OF IfcDirection := IfcBuild2Axes(RefDirection);
WHERE
LocationIs2D : SELF\IfcPlacement.Location.Dim = 2;
LocationIsCP : 'IFC4X3_DEV_20bdb3d.IFCCARTESIANPOINT' IN TYPEOF(SELF\IfcPlacement.Location);
RefDirIs2D : (NOT (EXISTS (RefDirection))) OR (RefDirection.Dim = 2);
END_ENTITY;