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IfcFaceBound

Definition from ISO/CD 10303-42:1992: A face bound is a loop which is intended to be used for bounding a face.

NOTE Corresponding STEP entity: face_bound. Please refer to ISO/IS 10303-42:1994, p. 139 for the final definition of the formal standard.

HISTORY New class in IFC Release 1.0

EXPRESS specification:

ENTITY IfcFaceBound
SUPERTYPE OF (IfcFaceOuterBound)
SUBTYPE OF ( IfcTopologicalRepresentationItem);
Bound  :  IfcLoop;
Orientation  :  BOOLEAN;
WHERE
WR1  :  'IFCTOPOLOGYRESOURCE.IFCPOLYLOOP' IN TYPEOF(Bound);
END_ENTITY;

Attribute definitions:

Bound  :  The loop which will be used as a face boundary.
Orientation  :  This indicated whether (TRUE) or not (FALSE) the loop has the same sense when used to bound the face as when first defined. If sense is FALSE the senses of all its component oriented edges are implicitly reversed when used in the face.

Formal Propositions:

WR1  :  Only polyloops shall be used for face bounds.

Inheritance graph

ENTITY IfcFaceBound;
ENTITY IfcRepresentationItem;
ENTITY IfcTopologicalRepresentationItem;
ENTITY IfcFaceBound;
Bound  :  IfcLoop;
Orientation  :  BOOLEAN;
END_ENTITY;