public override string GetStepParameters()
{
var parameters = new List <string>();
parameters.Add(Curve3D != null ? Curve3D.ToStepValue() : "$");
parameters.Add(AssociatedGeometry != null ? AssociatedGeometry.ToStepValue() : "$");
parameters.Add(MasterRepresentation != null ? MasterRepresentation.ToStepValue() : "$");
return(string.Join(", ", parameters.ToArray()));
}