﻿ IfcCartesianTransformationOperator3D

#### IfcCartesianTransformationOperator3D

Natural language names
 Kartesische Transformation - dreidimensional (3D) Cartesian Transformation Operator 3D Opérateur 3D de transformation cartésienne
Change log
ItemSPFXMLChangeDescription
IfcCartesianTransformationOperator3D
ScaleMODIFIEDType changed from REAL to IfcReal.
##### Semantic definitions at the entity
Entity definition

An IfcCartesianTransformationOperator defines a geometric transformation in three-dimensional space.

NOTE  Definition according to ISO/CD 10303-42:1992
A Cartesian transformation operator 3d defines a geometric transformation in three-dimensional space composed of translation, rotation, mirroring and uniform scaling. The list of normalized vectors u defines the columns of an orthogonal matrix T. These vectors are computed from the direction attributes axis1, axis2 and axis3 by the base axis function. If |T|= -1, the transformation includes mirroring.
NOTE  Entity adapted from cartesian_transformation_operator_3d defined in ISO10303-42.
HISTORY  New entity in IFC2x.
Attribute definitions
#AttributeTypeCardinalityDescription G
5Axis3IfcDirection? The exact direction of U[3], the derived Z axis direction.X
U
:=IfcBaseAxis(3,SELF\IfcCartesianTransformationOperator.Axis1, SELF\IfcCartesianTransformationOperator.Axis2,Axis3)
IfcDirectionL[3:3]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. X
Formal Propositions
RuleDescription
DimIs3DThe coordinate space dimensionality of this entity shall be 3.
Axis1Is3DThe inherited Axis1 should have (if given) the dimensionality of 3.
Axis2Is3DThe inherited Axis2 should have (if given) the dimensionality of 3.
Axis3Is3DThe Axis3 should have (if given) the dimensionality of 3.
##### Inherited definitions from supertypes
Entity inheritance
Attribute inheritance
#AttributeTypeCardinalityDescriptionG
IfcRepresentationItem
LayerAssignmentIfcPresentationLayerAssignment
@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
StyledByItemIfcStyledItem
@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
IfcGeometricRepresentationItem
IfcCartesianTransformationOperator
1Axis1IfcDirection? The direction used to determine U[1], the derived X axis direction.X
2Axis2IfcDirection? The direction used to determine U[2], the derived Y axis direction.X
3LocalOriginIfcCartesianPoint 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
4ScaleIfcReal? The scaling value specified for the transformation.X
Scl
:=NVL(Scale, 1.0)
IfcRealThe derived scale S of the transformation, equal to scale if that exists, or 1.0 otherwise. X
Dim
:=LocalOrigin.Dim
IfcDimensionCountThe space dimensionality of this class, determined by the space dimensionality of the local origin. X
IfcCartesianTransformationOperator3D
5Axis3IfcDirection? The exact direction of U[3], the derived Z axis direction.X
U
:=IfcBaseAxis(3,SELF\IfcCartesianTransformationOperator.Axis1, SELF\IfcCartesianTransformationOperator.Axis2,Axis3)
IfcDirectionL[3:3]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. X
##### Formal representations
XML Specification
``` <xs:element name="IfcCartesianTransformationOperator3D" type="ifc:IfcCartesianTransformationOperator3D" substitutionGroup="ifc:IfcCartesianTransformationOperator" nillable="true"/>  <xs:complexType name="IfcCartesianTransformationOperator3D">   <xs:complexContent>    <xs:extension base="ifc:IfcCartesianTransformationOperator">     <xs:sequence>      <xs:element name="Axis3" type="ifc:IfcDirection" nillable="true" minOccurs="0"/>     </xs:sequence>    </xs:extension>   </xs:complexContent>  </xs:complexType> ```
EXPRESS Specification
``` ENTITY IfcCartesianTransformationOperator3D  SUPERTYPE OF(IfcCartesianTransformationOperator3DnonUniform)  SUBTYPE OF (IfcCartesianTransformationOperator);   Axis3 : OPTIONAL IfcDirection;  DERIVE   U : LIST [3:3] OF IfcDirection := IfcBaseAxis(3,SELF\IfcCartesianTransformationOperator.Axis1, SELF\IfcCartesianTransformationOperator.Axis2,Axis3);  WHERE   DimIs3D : SELF\IfcCartesianTransformationOperator.Dim = 3;  Axis1Is3D : NOT(EXISTS(SELF\IfcCartesianTransformationOperator.Axis1)) OR (SELF\IfcCartesianTransformationOperator.Axis1.Dim = 3);  Axis2Is3D : NOT(EXISTS(SELF\IfcCartesianTransformationOperator.Axis2)) OR (SELF\IfcCartesianTransformationOperator.Axis2.Dim = 3);  Axis3Is3D : NOT(EXISTS(Axis3)) OR (Axis3.Dim = 3);END_ENTITY;  EXPRESS-G diagram ```