diff --git a/EGkOffsetCurve3d.h b/EGkOffsetCurve3d.h
index ee3e728..cf352ba 100644
--- a/EGkOffsetCurve3d.h
+++ b/EGkOffsetCurve3d.h
@@ -17,6 +17,7 @@
 #include "/EgtDev/Include/EGkPolyLine.h"
 #include "/EgtDev/Include/EGkCurve.h"
 #include "/EgtDev/Include/EGkCurveComposite.h"
+#include "/EgtDev/Include/EGkProjectCurveSurf.h"
 #include "/EgtDev/Include/EgtPointerOwner.h"
 
 
@@ -94,7 +95,7 @@ public :
 
 public :
    EGK_EXPORT bool Reset( void) ;
-   EGK_EXPORT bool Make( const PolyLine& PL, const VCT3DVECTOR& vOffDir, double dDist, int nType) ;
+   EGK_EXPORT bool Make( const PNT5AXVECTOR& vPnt5Ax, double dDist, int nType) ;
    EGK_EXPORT int GetCurveCount( void) { return int( m_CrvLst.size()) ; }
    EGK_EXPORT ICurve* GetCurve( void) ;
    EGK_EXPORT ICurve* GetLongerCurve( void) ;
diff --git a/EGkProjectCurveSurf.h b/EGkProjectCurveSurf.h
index af7c8fe..a9b3052 100644
--- a/EGkProjectCurveSurf.h
+++ b/EGkProjectCurveSurf.h
@@ -25,6 +25,17 @@
    #define EGK_EXPORT __declspec( dllimport)
 #endif
 
+enum P5AxAng {    // Tipologia di punto
+                  P5AX_TO_DELETE = -1 ,        // da cancellare
+                  P5AX_OUT = 0 ,               // aggiunto prima di inizio o dopo fine
+                  P5AX_STD = 1 ,               // standard
+                  P5AX_CVEX = 2 ,              // su angolo convesso
+                  P5AX_CONC = 3 ,              // in angolo concavo
+                  P5AX_BEFORE_CONC = 4 ,       // adiacente ad angolo concavo
+                  P5AX_AFTER_CONC = 5 ,        // adiacente ad angolo concavo
+                  P5AX_SMOOTH_CONC = 6         // zona concava curva, senza spigolo netto
+               };
+
 //----------------------------------------------------------------------------
 // Definizione di Punto 5assi e sue raccolte
 struct Point5ax {
@@ -49,7 +60,7 @@ typedef std::vector<Point5ax>        PNT5AXVECTOR ;    // vettore di Punti 5assi
 //----------------------------------------------------------------------------
 // Proiezione di una curva su una o più superfici a distanza minima
 EGK_EXPORT bool ProjectCurveOnSurf( const ICurve& crCrv, const CISURFPVECTOR& vpSurf,
-                                    double dLinTol, double dMaxSegmLen, bool bSharpEdges, PNT5AXVECTOR& vPt5ax) ;
+                                    double dLinTol, double dMaxSegmLen, bool bSharpEdges, PNT5AXVECTOR& vPt5ax, bool bNormOrTang = true) ;
 // Proiezione di una curva su una o più superfici lungo la direzione data (da o verso)
 EGK_EXPORT bool ProjectCurveOnSurf( const ICurve& crCrv, const CISURFPVECTOR& vpSurf, const Vector3d& vtDir,
                                     double dLinTol, double dMaxSegmLen, bool bSharpEdges, bool bFromVsTo, PNT5AXVECTOR& vPt5ax) ;
diff --git a/EGkStmFromCurves.h b/EGkStmFromCurves.h
index 70d9c99..42583c6 100644
--- a/EGkStmFromCurves.h
+++ b/EGkStmFromCurves.h
@@ -48,3 +48,4 @@ EGK_EXPORT ISurfTriMesh* GetSurfTriMeshSwept( const ISurfFlatRegion* pSfrSect, c
 EGK_EXPORT ISurfTriMesh* GetSurfTriMeshTransSwept( const ICurve* pSect, const ICurve* pGuide, bool bCapEnds, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfTriMesh* GetSurfTriMeshRuled( const Point3d& ptP, const ICurve* pCurve, double dLinTol = 10 * EPS_SMALL) ;
 EGK_EXPORT ISurfTriMesh* GetSurfTriMeshRuled( const ICurve* pCurve1, const ICurve* pCurve2, int nType, double dLinTol = 10 * EPS_SMALL) ;
+EGK_EXPORT ISurfTriMesh* GetSurfExtension( const ISurfTriMesh* pSrfTM, double dExtLen, int nLoop, int nSubCrv, int nType, double dLinTol) ;
diff --git a/EXeExecutor.h b/EXeExecutor.h
index e489eb6..9f7a603 100644
--- a/EXeExecutor.h
+++ b/EXeExecutor.h
@@ -432,6 +432,8 @@ EXE_EXPORT int  ExeCreateSurfBzRuledGuided( int nParentId, int nCrvId1, int nCrv
 EXE_EXPORT int  ExeCreateSurfBzSkinned( int nParentId, const INTVECTOR& nCrvId1, bool bCapEnds, double dLinTol) ;
 EXE_EXPORT int  ExeCreateSurfBzSwept( int nParentId, int nSectId, int nGuideId, const Vector3d& vtAx,
                                       bool bCapEnds, double dLinTol, int nRefType) ;
+EXE_EXPORT int  ExeCreateSurfExtension( int nParentId, int nSurfId, double dExtLen, int nCrv, int nSubCrv,
+                                        int nType, double dLinTol) ;
 
 // GeomDB Create Volume
 EXE_EXPORT int  ExeCreateVolZmap( int nParentId, const Point3d& ptIni, double dDimX,