The IfcCurveOnSurface enables the choice of curve types on parameteric surface.

NOTE  Definition according to ISO/CD 10303-42:1992
A curve_on_surface is a curve on a parametric surface. It may be any of the following:

• a pcurve or
• a surface curve, including the specialised subtypes of intersection curve and seam curve, or
• a composite curve on surface.

The curve on surface select type collects these curves together for reference purposes.

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

HISTORY  New type in IFC4.