IFC Release Specific Concept Description (IFC2X3)
Openings for Straight Geometry
Reference
<Reference field>
Version
1
Status
Draft
Relationships
History
First draft 6.7.2006
Authors
Sakari Lehtinen
Document Owner
TUT (Tampere University of Technology)
Description
000 - IFC2x2
TMP-021 - IFC2x2
<Building Element>
Openings
IfcRelVoidsElement
+ GlobalId
+ OwnerHistory >
Name
Description
+ RelatingBuildingElement >
+ RelatedOpeningElement >
IfcElement
IfcOpeningElement
+ GlobalId
+ OwnerHistory >
Name
Description
ObjectType
ObjectPlacement >
Representation >
Tag
For example IfcBeam
Relative to the placement of the
voided building element.
’Opening’ or ’Recess’. If
omitted the default value
is ’Opening’.
IfcLocalRelativePlacement
STRING
IfcProductDefinitionShape
Name
Description
+ Representations >
IfcShapeRepresentation
+ ContextOfItems >
RepresentationIdentifier
RepresentationType
+ Items >
Can be either Rectangle-, Circle-,
Arbitrary Straight Extruded - or
Arbitrary Curved -profile, or
Mapped Representation, or Brep
IfcSolidModel
IfcGeometricRepresentationContext
Implementation agreements:
-
This relationship between element and the opening element implies a Boolean Operation of
subtraction for the geometric bodies of Element and Opening Element.
-
The PlacementRelTo relationship of IfcLocalPlacement points to the local placement of the
same element, which is voided by the opening, i.e. referred to by
VoidsElement.RelatingBuildingElement.
-
The geometric representation of IfcOpeningElement is given by the IfcProductDefinitionShape
and IfcLocalPlacement allowing multiple geometric representations.
-
Representation of the opening element can be either Rectangular-, Circle-, Arbitrary Straight
Extruded – or Arbitrary Curved –profile, or Mapped Representation, or Brep. For further
information see the corresponding concept descriptions.
-
The extrusion of the opening element can be either horizontal or vertical. Horizontal means that
extrusion direction of the opening element is perpendicular to the extrusion direction of the
voided building element. Vertical means that the extrusion direction of the opening element is
parallel to the extrusion direction of the voided building element.
-
Opening elements must be inside the voided element. They shall not be used as arbitrary
cutting.
-
the size of the opening element should not exceed the bounding box of the voided element
-
the receiving system may increase the opening extrusion depth by an acceptable epsilon value
to avoid numerical problems with the faces
This document uses the official IAI View Definition Format version 1.0.6. The content of this document has to be certified by
the IAI before becoming part of an Official IAI View Definition.