8.9.3.17 IfcCartesianTransformationOperator3DnonUniform

RV ⓘ

8.9.3.17.1 Semantic definition

A Cartesian transformation operator 3d non uniform defines a geometric transformation in three-dimensional space composed of translation, rotation, mirroring and non uniform scaling. Non uniform scaling is given by three different scaling factors:

SELF\IfcCartesianTransformationOperator.Scale: the x axis scale factor
Scale2: the y axis scale factor
Scale3: the z axis scale factor

If the Scale factor (at supertype IfcCartesianTransformationOperator) is omitted, it defaults to 1.0. If the Scale2 or the Scale3 factor is omitted, it defaults to the value of Scale (the x axis scale factor).

8.9.3.17.2 Entity inheritance

8.9.3.17.3 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. IFC2x3-CHANGE The inverse attribute LayerAssignments has been added. IFC4-CHANGE The inverse attribute LayerAssignment has been restricted to max 1. Upward compatibility for file based exchange is guaranteed.
	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. IFC2x3-CHANGE The inverse attribute StyledByItem has been added.
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. `NVL(Scale, 1.0)` The derived scale S of the transformation, equal to scale if that exists, or 1.0 otherwise.
*	Dim	IfcDimensionCount	This attribute is formally derived. `LocalOrigin.Dim` The space dimensionality of this class, determined by the space dimensionality of the local origin.
IfcCartesianTransformationOperator3D (2)
5	Axis3	OPTIONAL IfcDirection	The exact direction of U[3], the derived Z axis direction.
*	U	LIST [3:3] OF IfcDirection	This attribute is formally derived. `IfcBaseAxis(3,SELF\IfcCartesianTransformationOperator.Axis1, SELF\IfcCartesianTransformationOperator.Axis2,Axis3)` The list of mutually orthogonal, normalized vectors defining the transformation matrix T. They are derived from the explicit attributes Axis3, Axis1, and Axis2 in that order.
Click to show 10 hidden inherited attributes Click to hide 10 inherited attributes
IfcCartesianTransformationOperator3DnonUniform (4)
6	Scale2	OPTIONAL IfcReal	The scaling value specified for the transformation along the axis 2. This is normally the y scale factor.
7	Scale3	OPTIONAL IfcReal	The scaling value specified for the transformation along the axis 3. This is normally the z scale factor.
*	Scl2	IfcReal	This attribute is formally derived. `NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl)` 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.
*	Scl3	IfcReal	This attribute is formally derived. `NVL(Scale3, SELF\IfcCartesianTransformationOperator.Scl)` The derived scale S(3) of the transformation along the axis 3 (normally the z axis), equal to Scale3 if that exists, or equal to the derived Scl1 (normally the x axis scale factor) otherwise.

Table 8.9.3.17.A

8.9.3.17.4 Formal propositions

Name	Description
Scale2GreaterZero	The derived scaling Scl2 shall be greater than zero.
`Scl2 > 0.0`
Scale3GreaterZero	The derived scaling Scl3 shall be greater than zero.
`Scl3 > 0.0`

Table 8.9.3.17.B

8.9.3.17.5 Formal representation

ENTITY IfcCartesianTransformationOperator3DnonUniform
 SUBTYPE OF (IfcCartesianTransformationOperator3D);
	Scale2 : OPTIONAL IfcReal;
	Scale3 : OPTIONAL IfcReal;
 DERIVE
	 Scl2 : IfcReal := NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl);
	 Scl3 : IfcReal := NVL(Scale3, SELF\IfcCartesianTransformationOperator.Scl);
 WHERE
	Scale2GreaterZero : Scl2 > 0.0;
	Scale3GreaterZero : Scl3 > 0.0;
END_ENTITY;