8.9.3.15 IfcCartesianTransformationOperator2DnonUniform
8.9.3.15.1 Semantic definition
A Cartesian transformation operator 2d non uniform defines a geometric transformation in two-dimensional space composed of translation, rotation, mirroring and non uniform scaling. Non uniform scaling is given by two different scaling factors:
- SELF\IfcCartesianTransformationOperator.Scale: the x axis scale factor
- Scale2: the y axis scale factor
If the Scale factor (at supertype IfcCartesianTransformationOperator) is omitted, it defaults to 1.0. If the Scale2 factor is omitted, it defaults to the value of Scale (the x axis scale factor).
8.9.3.15.2 Entity inheritance
-
- IfcCartesianTransformationOperator
- IfcAnnotationFillArea
- IfcBooleanResult
- IfcBoundingBox
- IfcCartesianPointList
- IfcCsgPrimitive3D
- IfcCurve
- IfcDirection
- IfcFaceBasedSurfaceModel
- IfcFillAreaStyleHatching
- IfcFillAreaStyleTiles
- IfcGeometricSet
- IfcHalfSpaceSolid
- IfcLightSource
- IfcPlacement
- IfcPlanarExtent
- IfcPoint
- IfcSectionedSpine
- IfcSegment
- IfcShellBasedSurfaceModel
- IfcSolidModel
- IfcSurface
- IfcTessellatedItem
- IfcTextLiteral
- IfcVector
8.9.3.15.3 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. |
|
| IfcCartesianTransformationOperator (6) | |||
| 1 | Axis1 | OPTIONAL IfcDirection |
The direction used to determine U[1], the derived X axis direction. |
| 2 | Axis2 | OPTIONAL IfcDirection |
The direction used to determine U[2], the derived Y axis direction. |
| 3 | LocalOrigin | IfcCartesianPoint |
The required translation, specified as a cartesian point. The actual translation included in the transformation is from the geometric origin to the local origin. |
| 4 | Scale | OPTIONAL IfcReal |
The scaling value specified for the transformation. |
| * | Scl | IfcReal |
This attribute is formally derived. The derived scale S of the transformation, equal to scale if that exists, or 1.0 otherwise. |
| * | Dim | IfcDimensionCount |
This attribute is formally derived. The space dimensionality of this class, determined by the space dimensionality of the local origin. |
| IfcCartesianTransformationOperator2D (1) | |||
| * | U | LIST [2:2] OF IfcDirection |
This attribute is formally derived. The list of mutually orthogonal, normalized vectors defining the transformation matrix T. They are derived from the explicit attributes Axis1 and Axis2 in that order. |
| Click to show 9 hidden inherited attributes Click to hide 9 inherited attributes | |||
| IfcCartesianTransformationOperator2DnonUniform (2) | |||
| 5 | Scale2 | OPTIONAL IfcReal |
The scaling value specified for the transformation along the axis 2. This is normally the y scale factor. |
| * | Scl2 | IfcReal |
This attribute is formally derived. The derived scale S(2) of the transformation along the axis 2 (normally the y axis), equal to Scale2 if that exists, or equal to the derived Scl1 (normally the x axis scale factor) otherwise. |
8.9.3.15.4 Formal propositions
| Name | Description |
|---|---|
| Scale2GreaterZero |
The derived scaling Scl2 shall be greater than zero. |
|
|
8.9.3.15.5 Formal representation
ENTITY IfcCartesianTransformationOperator2DnonUniform
SUBTYPE OF (IfcCartesianTransformationOperator2D);
Scale2 : OPTIONAL IfcReal;
DERIVE
Scl2 : IfcReal := NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl);
WHERE
Scale2GreaterZero : Scl2 > 0.0;
END_ENTITY;