IfcBSplineCurveForm

Semantic definitions at the type

Type definition

The IfcBSplineCurveForm represents a part of a curve of some sppecific form.

NOTE Definition according to ISO/CD 10303-42:1992
This type is used to indicate that the B-spline curve represents a part of a curve of some specific form.

NOTE Type adapted from b_spline_curve_form defined in ISO 10303-42.

HISTORY New type in IFC2x2.

Enumeration definition

Constant	Description
POLYLINE_FORM	A connected sequence of line segments represented by degree 1 B-spline basis functions.
CIRCULAR_ARC	An arc of a circle, or a complete circle represented by a B-spline curve.
ELLIPTIC_ARC	An arc of an ellipse, or a complete ellipse, represented by a B-spline curve.
PARABOLIC_ARC	An arc of finite length of a parabola represented by a B-spline curve.
HYPERBOLIC_ARC	An arc of finite length of one branch of a hyperbola represented by a B-spline curve.
UNSPECIFIED	A B-spline curve for which no particular form is specified.

Formal representations

XML Specification

 <xs:simpleType name="IfcBSplineCurveForm">

  <xs:restriction base="xs:string">

   <xs:enumeration value="polyline_form"/>

   <xs:enumeration value="circular_arc"/>

   <xs:enumeration value="elliptic_arc"/>

   <xs:enumeration value="parabolic_arc"/>

   <xs:enumeration value="hyperbolic_arc"/>

   <xs:enumeration value="unspecified"/>

  </xs:restriction>

 </xs:simpleType>

EXPRESS Specification


TYPE IfcBSplineCurveForm = ENUMERATION OF (

 POLYLINE_FORM, 
 CIRCULAR_ARC, 
 ELLIPTIC_ARC, 
 PARABOLIC_ARC, 
 HYPERBOLIC_ARC, 
 UNSPECIFIED);
END_TYPE;


 EXPRESS-G diagram

	BSpline Curve Form
	Forme de courbe Bspline