diff --git a/EXE_GdbModifyCurve.cpp b/EXE_GdbModifyCurve.cpp
index 3dca741..80ae05c 100644
--- a/EXE_GdbModifyCurve.cpp
+++ b/EXE_GdbModifyCurve.cpp
@@ -44,6 +44,7 @@
 #include "/EgtDev/Include/EgtPointerOwner.h"
 #include "/EgtDev/Include/EGkCalcPocketing.h"
 #include <EgtDev/Include/EGkSfrCreate.h>
+#include "/EgtDev/Include/EGkSurfBezier.h"
 #include <functional>
 
 
@@ -2490,6 +2491,230 @@ ExeProjectCurveOnSurfTmExt( int nCurveId, int nSurfTmId, int nGuideId, int nDest
 
 }
 
+//-------------------------------------------------------------------------------
+static bool
+MyProjectCurveOnSurfBz( int nCurveId, int nSurfBzId, const Vector3d& vtDir, int nDestGrpId,
+   double dLinTol, double dMaxSegmLen, int nRefType)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+      // recupero la curva e il suo riferimento
+      const ICurve* pCrv = GetCurve( pGeomDB->GetGeoObj( nCurveId)) ;
+   if ( pCrv == nullptr)
+      return false ;
+   Frame3d frCrv ;
+   if ( ! pGeomDB->GetGlobFrame( nCurveId, frCrv))
+      return false ;
+   // recupero la superficie bezier e il suo riferimento
+   const ISurfBezier* pSbz = GetSurfBezier( pGeomDB->GetGeoObj( nSurfBzId)) ;
+   // recupero la superficie trimesh
+   const ISurfTriMesh* pStm = pSbz->GetAuxSurf() ;
+   if ( pStm == nullptr)
+      return false ;
+   Frame3d frSbz ;
+   if ( ! pGeomDB->GetGlobFrame( nSurfBzId, frSbz))
+      return false ;
+   // recupero il riferimento del gruppo di destinazione
+   nDestGrpId = AdjustId( nDestGrpId) ;
+   Frame3d frDest ;
+   if ( ! pGeomDB->GetGroupGlobFrame( nDestGrpId, frDest))
+      return false ;
+   // porto la curva e il vettore nel riferimento della superficie
+   CurveLocal CrvLoc( pCrv, frCrv, frSbz) ;
+   if ( CrvLoc.Get() == nullptr)
+      return false ;
+   Vector3d vtDirL = GetVectorLocal( pGeomDB, vtDir, nRefType, frCrv) ;
+   vtDirL.LocToLoc( frCrv, frSbz) ;
+   // eseguo la proiezione
+   PNT5AXVECTOR vPt5ax ;
+   if ( ! ProjectCurveOnSurfTm( *CrvLoc.Get(), *pStm, vtDirL, dLinTol, dMaxSegmLen, vPt5ax))
+      return false ;
+   // inserisco la composita nel gruppo destinazione
+   PtrOwner<ICurveComposite> pCompo ;
+   for ( const auto& Pt5ax : vPt5ax) {
+      if ( IsNull( pCompo)) {
+         pCompo.Set( CreateCurveComposite()) ;
+         if ( IsNull( pCompo))
+            return false ;
+         pCompo->AddPoint( GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+      }
+      else
+         pCompo->AddLine( GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+   }
+   int nCompoId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pCompo)) ;
+   if ( nCompoId == GDB_ID_NULL)
+      return false ;
+   // aggiungo i versori nel gruppo destinazione
+   int nInd = 0 ;
+   for ( const auto& Pt5ax : vPt5ax) {
+      PtrOwner<IGeoVector3d> pGeoVct( CreateGeoVector3d()) ;
+      if ( IsNull( pGeoVct))
+         return false ;
+      pGeoVct->Set( 10 * GetLocToLoc( Pt5ax.vtDir, frSbz, frDest), GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+      int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pGeoVct)) ;
+      if ( nNewId == GDB_ID_NULL)
+         return false ;
+      pGeomDB->SetInfo( nNewId, "Ind", nInd ++) ;
+      pGeomDB->SetInfo( nNewId, "Par", Pt5ax.dPar) ;
+      pGeomDB->SetInfo( nNewId, "Flag", Pt5ax.nFlag) ;
+   }
+
+   return true ;
+}
+
+//-------------------------------------------------------------------------------
+bool
+ExeProjectCurveOnSurfBz( int nCurveId, int nSurfBzId, const Vector3d& vtDir, int nDestGrpId,
+   double dLinTol, double dMaxSegmLen, int nRefType)
+{
+   bool bOk = MyProjectCurveOnSurfBz( nCurveId, nSurfBzId, vtDir, nDestGrpId, dLinTol, dMaxSegmLen, nRefType) ;
+   ExeSetModified() ;
+   // se richiesto, salvo il comando Lua equivalente
+   if ( IsCmdLog()) {
+      string sLua = "EgtProjectCurveOnSurfBz(" + ToString( nCurveId) + "," +
+         ToString( nSurfBzId) + ",{" +
+         ToString( vtDir) + "}," +
+         ToString( nDestGrpId) + "," +
+         ToString( dLinTol) + "," +
+         ToString( dMaxSegmLen) + "," +
+         RefTypeToString( nRefType) + ")" +
+         " -- Ok=" + ToString( bOk) ;
+      LOG_INFO( GetCmdLogger(), sLua.c_str()) ;
+   }
+   return bOk ;
+
+}
+
+//-------------------------------------------------------------------------------
+static bool
+MyProjectCurveOnSurfBzExt( int nCurveId, int nSurfBzId, int nGuideId, int nDestGrpId,
+   double dLinTol, double dMaxSegmLen, bool bDirFromGuide)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+      // recupero la curva e il suo riferimento
+      const ICurve* pCrv = GetCurve( pGeomDB->GetGeoObj( nCurveId)) ;
+   if ( pCrv == nullptr)
+      return false ;
+   Frame3d frCrv ;
+   if ( ! pGeomDB->GetGlobFrame( nCurveId, frCrv))
+      return false ;
+   // recupero la superficie Bezier e il suo riferimento
+   const ISurfBezier* pSbz = GetSurfBezier( pGeomDB->GetGeoObj( nSurfBzId)) ;
+   // recupero la superficie trimesh
+   const ISurfTriMesh* pStm = pSbz->GetAuxSurf() ;
+   if ( pStm == nullptr)
+      return false ;
+   Frame3d frSbz ;
+   if ( ! pGeomDB->GetGlobFrame( nSurfBzId, frSbz))
+      return false ;
+   // recupero l'entità guida (punto, curva o superficie) e il suo riferimento
+   const IGeoPoint3d* pGdePnt = nullptr ;
+   const ICurve* pGdeCrv = nullptr ;
+   const ISurfTriMesh* pGdeStm = nullptr ;
+   pGdePnt = GetGeoPoint3d( pGeomDB->GetGeoObj( nGuideId)) ;
+   if ( pGdePnt == nullptr) {
+      pGdeCrv = GetCurve( pGeomDB->GetGeoObj( nGuideId)) ;
+      if ( pGdeCrv == nullptr) {
+         pGdeStm = GetSurfTriMesh( pGeomDB->GetGeoObj( nGuideId)) ;
+         if ( pGdeStm == nullptr)
+            return false ;
+      }
+   }
+   Frame3d frGde ;
+   if ( ! pGeomDB->GetGlobFrame( nGuideId, frGde))
+      return false ;
+   // recupero il riferimento del gruppo di destinazione
+   nDestGrpId = AdjustId( nDestGrpId) ;
+   Frame3d frDest ;
+   if ( ! pGeomDB->GetGroupGlobFrame( nDestGrpId, frDest))
+      return false ;
+   // porto la curva nel riferimento della superficie
+   CurveLocal CrvLoc( pCrv, frCrv, frSbz) ;
+   if ( CrvLoc.Get() == nullptr)
+      return false ;
+   // eseguo l'opportuna proiezione dopo aver portato l'entità guida nel riferimento della superficie
+   PNT5AXVECTOR vPt5ax ;
+   if ( pGdePnt != nullptr) {
+      PtrOwner<IGeoPoint3d> pGdeLoc( pGdePnt->Clone()) ;
+      if ( pGdeLoc == nullptr)
+         return false ;
+      pGdeLoc->LocToLoc( frGde, frSbz) ;
+      if ( ! ProjectCurveOnSurfTm( *CrvLoc.Get(), *pStm, *pGdeLoc, dLinTol, dMaxSegmLen, vPt5ax))
+         return false ;
+   }
+   else if ( pGdeCrv != nullptr) {
+      CurveLocal GdeLoc( pGdeCrv, frGde, frSbz) ;
+      if ( GdeLoc.Get() == nullptr)
+         return false ;
+      if ( ! ProjectCurveOnSurfTm( *CrvLoc.Get(), *pStm, *GdeLoc.Get(), dLinTol, dMaxSegmLen, vPt5ax))
+         return false ;
+   }
+   else { // pGdeStm != nullptr
+      SurfLocal GdeLoc( pGdeStm, frGde, frSbz) ;
+      const ISurfTriMesh* pGdeLoc = GetSurfTriMesh( GdeLoc.Get()) ;
+      if ( pGdeLoc == nullptr)
+         return false ;
+      if ( ! ProjectCurveOnSurfTm( *CrvLoc.Get(), *pStm, *pGdeLoc, dLinTol, dMaxSegmLen, vPt5ax))
+         return false ;
+   }
+   // inserisco la composita nel gruppo destinazione
+   PtrOwner<ICurveComposite> pCompo ;
+   for ( const auto& Pt5ax : vPt5ax) {
+      if ( IsNull( pCompo)) {
+         pCompo.Set( CreateCurveComposite()) ;
+         if ( IsNull( pCompo))
+            return false ;
+         pCompo->AddPoint( GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+      }
+      else
+         pCompo->AddLine( GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+   }
+   int nCompoId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pCompo)) ;
+   if ( nCompoId == GDB_ID_NULL)
+      return false ;
+   // aggiungo i versori nel gruppo destinazione
+   int nInd = 0 ;
+   for ( const auto& Pt5ax : vPt5ax) {
+      PtrOwner<IGeoVector3d> pGeoVct( CreateGeoVector3d()) ;
+      if ( IsNull( pGeoVct))
+         return false ;
+      Vector3d vtDir = ( bDirFromGuide ? Pt5ax.vtDir2 : Pt5ax.vtDir) ;
+      pGeoVct->Set( 10 * GetLocToLoc( vtDir, frSbz, frDest), GetLocToLoc( Pt5ax.ptP, frSbz, frDest)) ;
+      int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pGeoVct)) ;
+      if ( nNewId == GDB_ID_NULL)
+         return false ;
+      pGeomDB->SetInfo( nNewId, "Ind", nInd ++) ;
+      pGeomDB->SetInfo( nNewId, "Par", Pt5ax.dPar) ;
+      pGeomDB->SetInfo( nNewId, "Flag", Pt5ax.nFlag) ;
+   }
+
+   return true ;
+}
+
+//-------------------------------------------------------------------------------
+bool
+ExeProjectCurveOnSurfBzExt( int nCurveId, int nSurfBzId, int nGuideId, int nDestGrpId,
+   double dLinTol, double dMaxSegmLen, bool bDirFromGuide)
+{
+   bool bOk = MyProjectCurveOnSurfBzExt( nCurveId, nSurfBzId, nGuideId, nDestGrpId, dLinTol, dMaxSegmLen, bDirFromGuide) ;
+   ExeSetModified() ;
+   // se richiesto, salvo il comando Lua equivalente
+   if ( IsCmdLog()) {
+      string sLua = "EgtProjectCurveOnSurfBzExt(" + ToString( nCurveId) + "," +
+         ToString( nSurfBzId) + ",{" +
+         ToString( nGuideId) + "}," +
+         ToString( nDestGrpId) + "," +
+         ToString( dLinTol) + "," +
+         ToString( dMaxSegmLen) + "," +
+         ( bDirFromGuide ? "true" : "false") + ")" +
+         " -- Ok=" + ToString( bOk) ;
+      LOG_INFO( GetCmdLogger(), sLua.c_str()) ;
+   }
+   return bOk ;
+
+}
+
 //----------------------------------------------------------------------------
 int
 ExeCurveGetVoronoi( int nId, int nDestGrpId, int nBound, int* pnCount) 
diff --git a/LUA_GdbModifyCurve.cpp b/LUA_GdbModifyCurve.cpp
index 9b846c4..28f00ff 100644
--- a/LUA_GdbModifyCurve.cpp
+++ b/LUA_GdbModifyCurve.cpp
@@ -1001,6 +1001,58 @@ LuaProjectCurveOnSurfTmExt( lua_State* L)
    return 1 ;
 }
 
+//----------------------------------------------------------------------------
+static int
+LuaProjectCurveOnSurfBz( lua_State* L)
+{
+   // 4, 5, 6 o 7 parametri : nCurveId, nSurfBzId, vtDir, nDestGrpId [, dLinTol [, dMaxSegmLen] [, nRefType]]
+   int nCurveId ;
+   LuaCheckParam( L, 1, nCurveId)
+      int nSurfBzId ;
+   LuaCheckParam( L, 2, nSurfBzId)
+      Vector3d vtDir ;
+   LuaCheckParam( L, 3, vtDir)
+      int nDestGrpId ;
+   LuaCheckParam( L, 4, nDestGrpId)
+      double dLinTol = 0.01 ;
+   double dMaxSegmLen = INFINITO ;
+   int nRefType = RTY_DEFAULT ;
+   if ( LuaGetParam( L, 5, dLinTol)  &&
+      LuaGetParam( L, 6, dMaxSegmLen))
+      LuaGetParam( L, 7, nRefType) ;
+   LuaClearStack( L) ;
+   // proietto la curva su una trimesh secondo la direzione data
+   bool bOk = ExeProjectCurveOnSurfBz( nCurveId, nSurfBzId, vtDir, nDestGrpId, dLinTol, dMaxSegmLen, nRefType) ;
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
+//----------------------------------------------------------------------------
+static int
+LuaProjectCurveOnSurfBzExt( lua_State* L)
+{
+   // 4, 5, 6 o 7 parametri : nCurveId, nSurfBzId, nGuideId, nDestGrpId [, dLinTol [, dMaxSegmLen] [, bDirFromGuide]]
+   int nCurveId ;
+   LuaCheckParam( L, 1, nCurveId)
+      int nSurfBzId ;
+   LuaCheckParam( L, 2, nSurfBzId)
+      int nGuideId ;
+   LuaCheckParam( L, 3, nGuideId)
+      int nDestGrpId ;
+   LuaCheckParam( L, 4, nDestGrpId)
+      double dLinTol = 0.01 ;
+   double dMaxSegmLen = INFINITO ;
+   bool bDirFromGuide = false ;
+   if ( LuaGetParam( L, 5, dLinTol)  &&
+      LuaGetParam( L, 6, dMaxSegmLen))
+      LuaGetParam( L, 7, bDirFromGuide) ;
+   LuaClearStack( L) ;
+   // proietto la curva su una trimesh secondo la direzione data
+   bool bOk = ExeProjectCurveOnSurfBzExt( nCurveId, nSurfBzId, nGuideId, nDestGrpId, dLinTol, dMaxSegmLen, bDirFromGuide) ;
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
 //----------------------------------------------------------------------------
 static int
 LuaCurveGetVoronoi( lua_State* L)
@@ -1137,5 +1189,7 @@ LuaInstallGdbModifyCurve( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtCurveGetVoronoi", LuaCurveGetVoronoi) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtCurveMedialAxisAdv", LuaCurveMedialAxisAdv) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtCurveGetFatCurve", LuaCurveGetFatCurve) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtProjectCurveOnSurfBz", LuaProjectCurveOnSurfBz) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtProjectCurveOnSurfBzExt", LuaProjectCurveOnSurfBzExt) ;
    return bOk ;
 }