IfcConic

Definition from ISO/CD 10303-42:1992: A conic (IfcConic) is a planar curve which could be produced by intersecting a plane with a cone. A conic is defined in terms of its intrinsic geometric properties rather than being described in terms of other geometry. A conic class always has a placement coordinate system defined by a two or three dimensional placement. The parametric representation is defined in terms of this placement coordinate system.

NOTE Corresponding STEP entity: conic, only the following subtypes have been incorporated into IFC 1.0, 1.5 & 2.0: circle as IfcCircle, ellipse as IfcEllipse. The derived attribute Dim has been added at this level and was therefore demoted from the geometric_representation_item. Please refer to ISO/IS 10303-42:1994, p. 38 for the final definition of the formal standard.

HISTORY New class in IFC Release 1.0

EXPRESS specification:

ENTITY IfcConic

ABSTRACT SUPERTYPE OF

(ONEOF(IfcCircle, IfcEllipse))

SUBTYPE OF (

IfcCurve);

Position

IfcAxis2Placement;

END_ENTITY;

Attribute definitions:

Position

The location and orientation of the conic. Further details of the interpretation of this attribute are given for the individual subtypes."

Inheritance graph

ENTITY IfcConic;

ENTITY IfcRepresentationItem;

INVERSE

LayerAssignments

SET OF IfcPresentationLayerAssignment FOR AssignedItems;

StyledByItem

SET [0:1] OF IfcStyledItem FOR Item;

ENTITY IfcGeometricRepresentationItem;

ENTITY IfcCurve;

DERIVE

Dim

IfcDimensionCount := IfcCurveDim(SELF);

ENTITY IfcConic;

Position

IfcAxis2Placement;

END_ENTITY;