diff --git a/EXE_GdbCreateCurve.cpp b/EXE_GdbCreateCurve.cpp
index 858e449..fa6075f 100644
--- a/EXE_GdbCreateCurve.cpp
+++ b/EXE_GdbCreateCurve.cpp
@@ -2761,15 +2761,9 @@ ExeOffsetCurve3d( int nId, int nSurfId, double dDist, int nType, int* pnCount, d
    PNT5AXVECTOR vPt5ax ;
    if ( ! ProjectCurveOnSurf( *pCurve, vpSurf, dLinTol, dMaxSegLen, bSharpEdges, vPt5ax))
       return GDB_ID_NULL ;
-   PolyLine PL ;
-   VCT3DVECTOR vOffDir ;
-   for ( int i = 0 ; i < ssize( vPt5ax) ; ++i) {
-      PL.AddUPoint( i, vPt5ax[i].ptP) ;
-      vOffDir.push_back( vPt5ax[i].vtDir1) ;
-   }
    // eseguo l'offset
    OffsetCurve3d OffsCrv( dLinTol) ;
-   bool bOk = OffsCrv.Make( PL, vOffDir, dDist, nType) ;
+   bool bOk = OffsCrv.Make( vPt5ax, dDist, nType) ;
    // salvo le curve di offset
    int nRefId = nId ;
    int nCount = 0 ;
diff --git a/EXE_GdbCreateSurf.cpp b/EXE_GdbCreateSurf.cpp
index 79015a1..04acf97 100644
--- a/EXE_GdbCreateSurf.cpp
+++ b/EXE_GdbCreateSurf.cpp
@@ -3021,3 +3021,27 @@ ExeCreateSurfBzSwept( int nParentId, int nSectId, int nGuideId, const Vector3d&
   // restituisco l'identificativo della nuova entità
    return nNewId ;
 }
+
+//-------------------------------------------------------------------------------
+int
+ExeCreateSurfExtension( int nParentId, int nSurfId, double dExtLen, int nCrv, int nSubCrv,
+                        int nType, double dLinTol)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+   nParentId = AdjustId( nParentId) ;
+
+   // recupero la superficie
+   const ISurfTriMesh* pSurf = GetSurfTriMesh( pGeomDB->GetGeoObj( nSurfId)) ;
+   if ( pSurf == nullptr) {
+      const ISurfBezier* pSurfBz = GetSurfBezier( pGeomDB->GetGeoObj( nSurfId)) ;
+      if ( pSurfBz == nullptr)
+         return GDB_ID_NULL ;
+      pSurf = pSurfBz->GetAuxSurfRefined() ;
+   }
+
+   ISurfTriMesh* pExtension = GetSurfExtension( pSurf, dExtLen, nCrv, nSubCrv, nType, dLinTol) ;
+   int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nParentId, pExtension) ;
+
+   return nNewId ;
+}
diff --git a/LUA_GdbCreateSurf.cpp b/LUA_GdbCreateSurf.cpp
index a5e0957..73bddd8 100644
--- a/LUA_GdbCreateSurf.cpp
+++ b/LUA_GdbCreateSurf.cpp
@@ -1481,6 +1481,35 @@ LuaCreateSurfBzSwept( lua_State* L)
    return 1 ;
 }
 
+//-------------------------------------------------------------------------------
+static int
+LuaCreateSurfExtension( lua_State* L)
+{
+   // 3 o 7  parametri : ParentId, nSurfId, dExtLen [, nCrv] [, nSubCrv] [, nType] [, dTol]
+   int nParentId ;
+   LuaCheckParam( L, 1, nParentId)
+   int nSurfId ;
+   LuaCheckParam( L, 2, nSurfId)
+   double dExtLen ;
+   LuaCheckParam( L, 3, dExtLen)
+   int nCrv = 0 ;  // di default loop 0
+   int nSubCrv = -1 ;  // di default tutto estendo la superficie lungo tutto il loop
+   int nType = ICurve::OFF_CHAMFER ;
+   double dTol = LIN_TOL_STD ;
+   if ( LuaGetParam( L, 4, nCrv)) {
+        LuaGetParam( L, 5, nSubCrv) ;
+        LuaGetParam( L, 6, nType) ;
+        LuaGetParam( L, 7, dTol) ;
+   }
+   LuaClearStack( L) ;
+   int nId = ExeCreateSurfExtension( nParentId, nSurfId, dExtLen, nCrv, nSubCrv, nType, dTol) ;
+   if ( nId != GDB_ID_NULL)
+      LuaSetParam( L, nId) ;
+   else
+      LuaSetParam( L) ;
+   return 1 ;
+}
+
 //-------------------------------------------------------------------------------
 bool
 LuaInstallGdbCreateSurf( LuaMgr& luaMgr)
@@ -1537,5 +1566,6 @@ LuaInstallGdbCreateSurf( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfBzRuledGuided", LuaCreateSurfBzRuledGuided) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfBzSkinned", LuaCreateSurfBzSkinned) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfBzSwept", LuaCreateSurfBzSwept) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtSurfExtend", LuaCreateSurfExtension) ;
    return bOk ;
 }