IfcBoundingBox

Definition from ISO/CD 10303-42:1992: A box domain is an orthogonal box parallel to the axes of the geometric coordinate system which may be used to limit the domain of a half space solid. A box domain is specified by the coordinates of the bottom left corner, and the lengths of the sides measured in the directions of the coordinate axes.

Definition from IAI: Every semantic object having a physical extent might have a minimum default representation of a bounding box. The bounding box is therefore also used as minimal geometric representation for any geometrically represented object. Therefore the IfcBoundingBox is subtyped from IfcGeometricRepresentationItem.

> NOTE: Corresponding STEP entity : box_domain, please refer to ISO/IS 10303-42:1994, p. 186 for the final definition of the formal standard. In IFC the bounding box can also be used outside of the context of an IfcBoxedHalfSpace.

> HISTORY: New entity in IFC Release 1.0 .

Illustration:

| The IfcBoundingBox is defined with an own location which can be used to place the IfcBoundingBox relative to the geometric coordinate system. The IfcBoundingBox is defined by the lower left corner (Corner) and the upper right corner (XDim, YDim, ZDim measured within the parent co-ordinate system).

EXPRESS specification:

ENTITY IfcBoundingBox
SUBTYPE OF ( | IfcGeometricRepresentationItem);
Corner | : | IfcCartesianPoint;
XDim | : | IfcPositiveLengthMeasure;
YDim | : | IfcPositiveLengthMeasure;
ZDim | : | IfcPositiveLengthMeasure;
DERIVE
Dim | : | IfcDimensionCount := 3;
END_ENTITY;

Attribute definitions:

Corner | : | Location of the bottom left corner (having the minimum values).
XDim | : | Length attribute (measured along the edge parallel to the X Axis)
YDim | : | Width attribute (measured along the edge parallel to the Y Axis)
ZDim | : | Height attribute (measured along the edge parallel to the Z Axis).
Dim | : | The space dimensionality of this class, it is always 3.

Inheritance graph

ENTITY IfcBoundingBox;
ENTITY IfcRepresentationItem;
INVERSE
LayerAssignments | : | SET OF IfcPresentationLayerAssignment FOR AssignedItems;
StyledByItem | : | SET [0:1] OF IfcStyledItem FOR Item;
ENTITY IfcGeometricRepresentationItem;
ENTITY IfcBoundingBox;
Corner | : | IfcCartesianPoint;
XDim | : | IfcPositiveLengthMeasure;
YDim | : | IfcPositiveLengthMeasure;
ZDim | : | IfcPositiveLengthMeasure;
DERIVE
Dim | : | IfcDimensionCount := 3;
END_ENTITY;