diff --git a/EGkSbzFromCurves.h b/EGkSbzFromCurves.h
index 386e99c..1d86cc2 100644
--- a/EGkSbzFromCurves.h
+++ b/EGkSbzFromCurves.h
@@ -44,6 +44,7 @@ EGK_EXPORT ISurfBezier* GetSurfBezierByScrewing( const ICurve* pCurve, const Poi
 //EGK_EXPORT ISurfBezier* GetSurfBezierTransSwept( const ICurve* pSect, const ICurve* pGuide, bool bCapEnds, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfBezier* GetSurfBezierRuled( const Point3d& ptP, const ICurve* pCurve, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfBezier* GetSurfBezierRuled( const ICurve* pCurve1, const ICurve* pCurve2, int nType, double dLinTol = 10 * EPS_SMALL) ;
+EGK_EXPORT ISurfBezier* GetSurfBezierRuledSmooth( const ICurve* pCurve1, const ICurve* pCurve2, double dSampleLen = 10) ;
 EGK_EXPORT ISurfBezier* GetSurfBezierRuledGuided( const ICurve* pCurve1, const ICurve* pCurve2, const BIPNTVECTOR& vCrv, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfBezier* GetSurfBezierSkinned( const CICURVEPVECTOR& vCrv, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfBezier* GetSurfBezierSweptInPlane( const ICurve* pSect, const ICurve* pGuide, const Vector3d& vtNorm, bool bCapEnds, double dLinTol = 10 * EPS_SMALL) ;
diff --git a/EGkSurfBezier.h b/EGkSurfBezier.h
index 42379b0..0e81ad3 100644
--- a/EGkSurfBezier.h
+++ b/EGkSurfBezier.h
@@ -104,6 +104,7 @@ class __declspec( novtable) ISurfBezier : public ISurf
       virtual bool RemoveCollapsedSpans() = 0 ;
       virtual PNTVECTOR GetAllControlPoints( void) const = 0 ;
       virtual bool LimitSurfToTrimmedRegion( void) = 0 ;
+      virtual bool CreateSmoothRuledByTwoCurves( const ICurve* pCurve0, const ICurve* pCurve1, double dSampleLen) = 0 ;
 } ;
 
 //-----------------------------------------------------------------------------