IfcCartesianTransformationOperator2DnonUniform

Definition from IAI: 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 omited, it defaults to 1.0. If the Scale2 factor is omited, 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 IFC Release 2x.

EXPRESS specification:

ENTITY IfcCartesianTransformationOperator2DnonUniform

SUBTYPE OF (

IfcCartesianTransformationOperator2D);

Scale2

OPTIONAL REAL;

DERIVE

Scl2

REAL := NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl);

WHERE

WR1

Scl2 > 0.0;

END_ENTITY;

Attribute definitions:

Scale2	:	The scaling value specified for the transformation along the axis 2. This is normally the y scale factor.
Scl2	:	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.

Formal Propositions:

WR1

The derived scaling Scl2 shall be greater than zero.

Inheritance graph

ENTITY IfcCartesianTransformationOperator2DnonUniform;

ENTITY IfcRepresentationItem;

INVERSE

LayerAssignments

SET OF IfcPresentationLayerAssignment FOR AssignedItems;

StyledByItem

SET [0:1] OF IfcStyledItem FOR Item;

ENTITY IfcGeometricRepresentationItem;

ENTITY IfcCartesianTransformationOperator;

Axis1

OPTIONAL IfcDirection;

Axis2

OPTIONAL IfcDirection;

LocalOrigin

IfcCartesianPoint;

Scale

OPTIONAL REAL;

DERIVE

Scl

REAL := NVL(Scale, 1.0);

Dim

IfcDimensionCount := LocalOrigin.Dim;

ENTITY IfcCartesianTransformationOperator2D;

DERIVE

LIST [2:2] OF IfcDirection := IfcBaseAxis(2,SELF\IfcCartesianTransformationOperator.Axis1,
SELF\IfcCartesianTransformationOperator.Axis2,?);

ENTITY IfcCartesianTransformationOperator2DnonUniform;

Scale2

OPTIONAL REAL;

DERIVE

Scl2

REAL := NVL(Scale2, SELF\IfcCartesianTransformationOperator.Scl);

END_ENTITY;