8.9.3.2 IfcAxis2Placement2D

AbRV ⓘ

8.9.3.2.1 Semantic definition

The IfcAxis2Placement2D provides location and orientation to place items in a two-dimensional space. The attribute RefDirection defines the x axis, the y axis is derived. If the attribute RefDirection is not given, the placement defaults to P[1] (x-axis) as [1.,0.] and P[2] (y-axis) as [0.,1.].

Figure 8.9.3.2.A illustrates the definition of the IfcAxis2Placement2D within the two-dimensional coordinate system.

8.9.3.2.2 Entity inheritance

8.9.3.2.3 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.
IfcPlacement (2)
1	Location	IfcPoint	The geometric position of a reference point, such as the center of a circle, of the item to be located.
*	Dim	IfcDimensionCount	This attribute is formally derived. `Location.Dim` The space dimensionality of this class, derived from the dimensionality of the location.
Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes
IfcAxis2Placement2D (2)
2	RefDirection	OPTIONAL IfcDirection	The direction used to determine the direction of the local X axis. If a value is omitted that it defaults to [1.0, 0.0.].
*	P	LIST [2:2] OF IfcDirection	This attribute is formally derived. `IfcBuild2Axes(RefDirection)` P[1]: The normalized direction of the placement X Axis. This is [1.0,0.0] if RefDirection is omitted. P[2]: The normalized direction of the placement Y Axis. This is a derived attribute and is orthogonal to P[1]. If RefDirection is omitted, it defaults to [0.0,1.0]

Table 8.9.3.2.N

8.9.3.2.4 Formal propositions

Name	Description
LocationIs2D	No description available.
`SELF\IfcPlacement.Location.Dim = 2`
LocationIsCP	No description available.
`'IFC4X3_ADD2.IFCCARTESIANPOINT' IN TYPEOF(SELF\IfcPlacement.Location)`
RefDirIs2D	No description available.
`(NOT (EXISTS (RefDirection))) OR (RefDirection.Dim = 2)`

Table 8.9.3.2.O

8.9.3.2.5 Examples

Figure 8.9.3.2.B

Wall Extrusion
Figure 8.9.3.2.C

Fixed Reference Swept Area Solid
Figure 8.9.3.2.D

Beam Revolved Solid
Figure 8.9.3.2.E

Slab Tessellated Unique Vertices
Figure 8.9.3.2.F

Curve Parameters In Degrees
Figure 8.9.3.2.G

Curve Parameters In Radians
Figure 8.9.3.2.H

Polygonal Face Tessellation
Figure 8.9.3.2.I

Grid Placement
Figure 8.9.3.2.J

Cube Advanced Brep
Figure 8.9.3.2.K

Beam Curved I Shape Tessellated
Figure 8.9.3.2.L

Sectioned Solid Horizontal
Figure 8.9.3.2.M

Linear Placement Of Signal

8.9.3.2.6 Formal representation

ENTITY IfcAxis2Placement2D
 SUBTYPE OF (IfcPlacement);
	RefDirection : OPTIONAL IfcDirection;
 DERIVE
	 P : LIST [2:2] OF IfcDirection := IfcBuild2Axes(RefDirection);
 WHERE
	LocationIs2D : SELF\IfcPlacement.Location.Dim = 2;
	LocationIsCP : 'IFC4X3_ADD2.IFCCARTESIANPOINT' IN TYPEOF(SELF\IfcPlacement.Location);
	RefDirIs2D : (NOT (EXISTS (RefDirection))) OR (RefDirection.Dim = 2);
END_ENTITY;