IFC 4.3.x development

8.9.2.8 IfcKnotType

8.9.2.8.1 Semantic definitions at the entity

The IfcKnotType indicates the particular form of b-spline knots.

NOTE  Definition according to ISO/CD 10303-42:1992
This type indicates that the B-spline knots shall have a particularly simple form enabling the knots themselves to be defaulted.

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

HISTORY  New type in IFC4.

Items

UNIFORM_KNOTS

The form of knots appropriate for a uniform B-spline curve.

QUASI
PIECEWISE
UNSPECIFIED

The type of knots is not specified. This includes the case of non uniform knots.

8.9.2.8.1 Formal representations

TYPE IfcKnotType = ENUMERATION OF
	(UNIFORM_KNOTS
	,QUASI_UNIFORM_KNOTS
	,PIECEWISE_BEZIER_KNOTS
	,UNSPECIFIED);
END_TYPE;