IfcConic

Semantic definitions at the entity

Entity definition

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

Attribute definitions

#	Attribute	Type	Cardinality	Description	A
1	Position	IfcAxis2Placement	[1:1]	The location and orientation of the conic. Further details of the interpretation of this attribute are given for the individual subtypes."	X

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	A
IfcRepresentationItem
IfcGeometricRepresentationItem
IfcCurve
	Dim :=IfcCurveDim(SELF)	IfcDimensionCount	[1:1]	The space dimensionality of this abstract class, defined differently for all subtypes, i.e. for IfcLine, IfcConic and IfcBoundedCurve.	X
IfcConic
1	Position	IfcAxis2Placement	[1:1]	The location and orientation of the conic. Further details of the interpretation of this attribute are given for the individual subtypes."	X

Formal representations

XSD Specification

 <xs:element name="IfcConic" type="ifc:IfcConic" abstract="true" substitutionGroup="ifc:IfcCurve" nillable="true"/>

 <xs:complexType name="IfcConic" abstract="true">

  <xs:complexContent>

   <xs:extension base="ifc:IfcCurve">

    <xs:sequence>

     <xs:element name="Position">

      <xs:complexType>

       <xs:group ref="ifc:IfcAxis2Placement"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcConic

 ABSTRACT SUPERTYPE OF(IfcCircle)

 SUBTYPE OF (IfcCurve);

  Position : IfcAxis2Placement;

END_ENTITY;

 EXPRESS-G diagram