IfcCartesianTransformationOperator2DnonUniform

BACnet MVD

#### IfcCartesianTransformationOperator2DnonUniform

Natural language names

| Kartesische Transformation - zweidimensional nicht gleichmäßig (2D)
| Cartesian Transformation Operator2 Dnon Uniform
| Opérateur 2D de transformation cartésienne non uniforme

Change log

Item | SPF | XML | Change | Description
--- | --- | --- | --- | ---
IFC4 Addendum 1
IfcCartesianTransformationOperator2DnonUniform |  |  |  |
Scale |  |  | MODIFIED | Type changed from REAL to IfcReal.
Scale2 |  |  | MODIFIED | Type changed from REAL to IfcReal.

##### Semantic definitions at the entity

Entity 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).

> NOTE The scale factor (Scl) defined at the supertype IfcCartesianTransformationOperator is used to express the calculated Scale factor (normally x axis scale factor).

> HISTORY New entity in IFC2x.

Attribute definitions

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
5 | Scale2 | IfcReal | ? | The scaling value specified for the transformation along the axis 2. This is normally the y scale factor. | X | X
| Scl2 :=NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl) | IfcReal |  | 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. | X | X

Formal Propositions

Rule | Description
--- | ---
Scale2GreaterZero | The derived scaling Scl2 shall be greater than zero.

##### Inherited definitions from supertypes

Entity inheritance
Attribute inheritance

# | Attribute | Type | Cardinality | Description | B
--- | --- | --- | --- | --- | ---
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.

> 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.

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.

> IFC2x3 CHANGE The inverse attribute StyledByItem has been added.

X

X

IfcGeometricRepresentationItem
IfcCartesianTransformationOperator
1 | Axis1 | IfcDirection | ? | The direction used to determine U[1], the derived X axis direction. | X | X
2 | Axis2 | IfcDirection | ? | The direction used to determine U[2], the derived Y axis direction. | X | X
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. | X | X
4 | Scale | IfcReal | ? | The scaling value specified for the transformation. | X | X
| Scl :=NVL(Scale, 1.0) | IfcReal |  | The derived scale S of the transformation, equal to scale if that exists, or 1.0 otherwise. | X | X
| Dim :=LocalOrigin.Dim | IfcDimensionCount |  | The space dimensionality of this class, determined by the space dimensionality of the local origin. | X | X
IfcCartesianTransformationOperator2D
| U :=IfcBaseAxis(2,SELF\IfcCartesianTransformationOperator.Axis1, SELF\IfcCartesianTransformationOperator.Axis2,?) | IfcDirection | L[2:2] | 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. | X | X
IfcCartesianTransformationOperator2DnonUniform
5 | Scale2 | IfcReal | ? | The scaling value specified for the transformation along the axis 2. This is normally the y scale factor. | X | X
| Scl2 :=NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl) | IfcReal |  | 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. | X | X

##### Formal representations

XML Specification
`<xs:element name="IfcCartesianTransformationOperator2DnonUniform" type="ifc:IfcCartesianTransformationOperator2DnonUniform" substitutionGroup="ifc:IfcCartesianTransformationOperator2D" nillable="true"/>
<xs:complexType name="IfcCartesianTransformationOperator2DnonUniform">
<xs:complexContent>
<xs:extension base="ifc:IfcCartesianTransformationOperator2D">
<xs:attribute name="Scale2" type="ifc:IfcReal" use="optional"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
`
EXPRESS Specification
`ENTITY IfcCartesianTransformationOperator2DnonUniform
SUBTYPE OF (IfcCartesianTransformationOperator2D);
Scale2 : OPTIONAL IfcReal;
DERIVE
Scl2 : IfcReal := NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl);
WHERE
Scale2GreaterZero : Scl2 > 0.0;
END_ENTITY;

EXPRESS-G diagram

`

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