diff --git a/EXE_GeoInters.cpp b/EXE_GeoInters.cpp
index 46778c3..02fbc82 100644
--- a/EXE_GeoInters.cpp
+++ b/EXE_GeoInters.cpp
@@ -371,36 +371,10 @@ ExeLineSurfTmInters( const Point3d& ptP, const Vector3d& vtDir, int nId, int nRe
 
 //-------------------------------------------------------------------------------
 static int
-MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDestGrpId, int nRefType, double dToler,
-                     int& nPntCount, int& nCrvCount, int& nSrfCount)
+MyAddPlaneStmIntersResultToGeomDB( IGeomDB * pGeomDB, const PNTVECTOR& vPnt, const BIPNTVECTOR& vBpt, const TRIA3DVECTOR& vTria, 
+                                   const Frame3d& frOrig, const Frame3d& frDest, int nId, int nDestGrpId, const Vector3d& vtExtr, 
+                                   double dToler, int& nPntCount, int& nCrvCount, int& nSrfCount)
 {
-   IGeomDB* pGeomDB = GetCurrGeomDB() ;
-   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
-  // recupero la superficie TriMesh
-   const ISurfTriMesh* pStm = GetSurfTriMesh( pGeomDB->GetGeoObj( nId)) ;
-   if ( pStm == nullptr)
-      return GDB_ID_NULL ;
-  // recupero il suo riferimento globale
-   Frame3d frSurf ;
-   if ( ! pGeomDB->GetGlobFrame( nId, frSurf))
-      return GDB_ID_NULL ;
-  // recupero il riferimento del gruppo di destinazione
-   Frame3d frDest ;
-   if ( ! pGeomDB->GetGroupGlobFrame( nDestGrpId, frDest))
-      return GDB_ID_NULL ;
-  // porto in locale il punto e la normale del piano
-   Point3d ptOnL = GetPointLocal( pGeomDB, ptOn, nRefType, frSurf) ;
-   Vector3d vtNL = GetVectorLocal( pGeomDB, vtN, nRefType, frSurf) ;
-  // calcolo il piano di intersezione
-   Plane3d plPlane ;
-   if ( ! plPlane.Set( ptOnL, vtNL))
-      return GDB_ID_NULL ;
-  // eseguo l'intersezione
-   PNTVECTOR vPnt ;
-   BIPNTVECTOR vBpt ;
-   TRIA3DVECTOR vTria ;
-   if ( ! IntersPlaneSurfTm( plPlane, *pStm, vPnt, vBpt, vTria))
-      return GDB_ID_NULL ;
   // Inserisco il risultato nel DB
    int nFirstId = GDB_ID_NULL ;
   // Inserisco i punti nel DB
@@ -412,13 +386,13 @@ MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDes
      // setto il punto
       pGeoPnt->Set(  vPnt[i]) ;
      // porto il punto nel riferimento destinazione
-      pGeoPnt->LocToLoc( frSurf, frDest) ;
+      pGeoPnt->LocToLoc( frOrig, frDest) ;
      // lo inserisco nel DB geometrico
       int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pGeoPnt)) ;
       if ( nNewId == GDB_ID_NULL)
          return GDB_ID_NULL ;
      // copio il materiale
-     if ( ! pGeomDB->CopyMaterial( nId, nNewId))
+      if ( ! pGeomDB->CopyMaterial( nId, nNewId))
          return GDB_ID_NULL ;
      // aggiorno contatori
       if ( nFirstId == GDB_ID_NULL)
@@ -455,8 +429,8 @@ MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDes
          Point3d ptEnd = vBpt[nInd].second ;
         // provo ad accodarlo alla composita
          bAdded = ( Dist( ptStart, ptEnd) > dToler / 2  &&
-                    pLine->Set( ptStart, ptEnd)  &&
-                    pCrvCompo->AddCurve( Release( pLine), true, dToler)) ;
+            pLine->Set( ptStart, ptEnd)  &&
+            pCrvCompo->AddCurve( Release( pLine), true, dToler)) ;
          ptNear = ( bAdded ? ptEnd : ptStart) ;
       }
      // se lunghezza curva inferiore a 5 volte la tolleranza, la ignoro
@@ -466,24 +440,24 @@ MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDes
      // se curva chiusa entro 5 volte la tolleranza ma considerata aperta, la chiudo bene
       Point3d ptStart, ptEnd ;
       if ( pCrvCompo->GetStartPoint( ptStart)  &&
-           pCrvCompo->GetEndPoint( ptEnd)  &&
-           AreSamePointEpsilon( ptStart, ptEnd, 5. * dToler)  &&
-           ! AreSamePointApprox( ptStart, ptEnd)) {
-        // porto il punto finale a coincidere esattamente con l'inizio
+         pCrvCompo->GetEndPoint( ptEnd)  &&
+         AreSamePointEpsilon( ptStart, ptEnd, 5. * dToler)  &&
+         ! AreSamePointApprox( ptStart, ptEnd)) {
+         // porto il punto finale a coincidere esattamente con l'inizio
          pCrvCompo->ModifyEnd( ptStart) ;
       }
      // assegno estrusione come direzione normale al piano
-      pCrvCompo->SetExtrusion( plPlane.GetVersN()) ;
+      pCrvCompo->SetExtrusion( vtExtr) ;
      // unisco segmenti allineati
       pCrvCompo->MergeCurves( 0.5 * dToler, ANG_TOL_STD_DEG) ;
      // porto la curva nel riferimento destinazione
-      pCrvCompo->LocToLoc( frSurf, frDest) ;
+      pCrvCompo->LocToLoc( frOrig, frDest) ;
      // la inserisco nel DB geometrico
       int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pCrvCompo)) ;
       if ( nNewId == GDB_ID_NULL)
          return GDB_ID_NULL ;
      // copio il materiale
-     if ( ! pGeomDB->CopyMaterial( nId, nNewId))
+      if ( ! pGeomDB->CopyMaterial( nId, nNewId))
          return GDB_ID_NULL ;
      // aggiorno contatori
       if ( nFirstId == GDB_ID_NULL)
@@ -495,7 +469,7 @@ MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDes
    if ( ! StmFts.Start())
       return GDB_ID_NULL ;
    for ( int i = 0 ; i < int( vTria.size()) ; ++ i)
-     // inserisco il triangolo nella nuova superficie
+      // inserisco il triangolo nella nuova superficie
       StmFts.AddTriangle( vTria[i]) ;
   // valido la superficie e calcolo le adiacenze
    if ( ! StmFts.End())
@@ -504,19 +478,57 @@ MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDes
    PtrOwner<ISurfTriMesh> pNewStm( StmFts.GetSurf()) ;
    if ( ! IsNull( pNewStm)  &&  pNewStm->GetTriangleCount() > 0) {
      // porto la superficie nel riferimento destinazione
-      pNewStm->LocToLoc( frSurf, frDest) ;
+      pNewStm->LocToLoc( frOrig, frDest) ;
      // la inserisco nel DB
       int nNewId = pGeomDB->AddGeoObj( GDB_ID_NULL, nDestGrpId, Release( pNewStm)) ;
       if ( nNewId == GDB_ID_NULL)
          return GDB_ID_NULL ;
      // copio il materiale
-     if ( ! pGeomDB->CopyMaterial( nId, nNewId))
+      if ( ! pGeomDB->CopyMaterial( nId, nNewId))
          return GDB_ID_NULL ;
      // aggiorno contatori
       if ( nFirstId == GDB_ID_NULL)
          nFirstId = nNewId ;
       ++ nSrfCount ;
    }
+
+   return nFirstId ;
+}
+//-------------------------------------------------------------------------------
+static int
+MyPlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDestGrpId, int nRefType, double dToler,
+                     int& nPntCount, int& nCrvCount, int& nSrfCount)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+  // recupero la superficie TriMesh
+   const ISurfTriMesh* pStm = GetSurfTriMesh( pGeomDB->GetGeoObj( nId)) ;
+   if ( pStm == nullptr)
+      return GDB_ID_NULL ;
+  // recupero il suo riferimento globale
+   Frame3d frSurf ;
+   if ( ! pGeomDB->GetGlobFrame( nId, frSurf))
+      return GDB_ID_NULL ;
+  // recupero il riferimento del gruppo di destinazione
+   Frame3d frDest ;
+   if ( ! pGeomDB->GetGroupGlobFrame( nDestGrpId, frDest))
+      return GDB_ID_NULL ;
+  // porto in locale il punto e la normale del piano
+   Point3d ptOnL = GetPointLocal( pGeomDB, ptOn, nRefType, frSurf) ;
+   Vector3d vtNL = GetVectorLocal( pGeomDB, vtN, nRefType, frSurf) ;
+  // calcolo il piano di intersezione
+   Plane3d plPlane ;
+   if ( ! plPlane.Set( ptOnL, vtNL))
+      return GDB_ID_NULL ;
+  // eseguo l'intersezione
+   PNTVECTOR vPnt ;
+   BIPNTVECTOR vBpt ;
+   TRIA3DVECTOR vTria ;
+   if ( ! IntersPlaneSurfTm( plPlane, *pStm, vPnt, vBpt, vTria))
+      return GDB_ID_NULL ;
+  // inserisco il risultato dell'intersezione nel DB
+   int nFirstId = MyAddPlaneStmIntersResultToGeomDB( pGeomDB, vPnt, vBpt, vTria, frSurf, frDest, nId, nDestGrpId, plPlane.GetVersN(), dToler, 
+                                                     nPntCount, nCrvCount, nSrfCount) ; 
   // restituisco l'identificativo della prima nuova entità
    return nFirstId ;
 }
@@ -555,6 +567,98 @@ ExePlaneSurfTmInters( const Point3d& ptOn, const Vector3d& vtN, int nId, int nDe
    return nFirstId ;
 }
 
+//-------------------------------------------------------------------------------
+static int
+MyParPlanesSurfTmInters( const Vector3d& vtN, const PNTVECTOR& vPntPlanes, int nId, int nDestGrpId, int nRefType, double dToler, int& nGrpCount)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+  // recupero la superficie TriMesh
+   const ISurfTriMesh* pStm = GetSurfTriMesh( pGeomDB->GetGeoObj( nId)) ;
+   if ( pStm == nullptr)
+      return GDB_ID_NULL ;
+  // recupero il suo riferimento globale
+   Frame3d frSurf ;
+   if ( ! pGeomDB->GetGlobFrame( nId, frSurf))
+      return GDB_ID_NULL ;
+  // recupero il riferimento del gruppo di destinazione
+   Frame3d frDest ;
+   if ( ! pGeomDB->GetGroupGlobFrame( nDestGrpId, frDest))
+      return GDB_ID_NULL ;
+
+  // porto in locale la normale del piano   
+   Vector3d vtNL = GetVectorLocal( pGeomDB, vtN, nRefType, frSurf) ;
+  // costruisco il frame dei piani
+   Frame3d frPlanes ; 
+   frPlanes.Set( ORIG, vtNL) ;
+   
+  // intersezione fra superficie e piani paralleli
+   IntersParPlanesSurfTm intPlStm( frPlanes, *pStm) ;
+   
+   int nFirstGrpId = GDB_ID_NULL ; 
+   for ( size_t i = 0 ; i < vPntPlanes.size() ; i++) {      
+      
+     // creo il layer in cui salvare 
+      int nGrpId = pGeomDB->AddGroup( GDB_ID_NULL, nDestGrpId, GLOB_FRM) ;
+      nGrpCount ++ ;
+      if ( nFirstGrpId == GDB_ID_NULL)
+         nFirstGrpId = nGrpId ;
+
+     // cerco l'intersezione con il piano
+      Point3d ptOnL = GetPointLocal( pGeomDB, vPntPlanes[i], nRefType, frSurf) ;
+      PNTVECTOR vPnt ;
+      BIPNTVECTOR vBpt ;
+      TRIA3DVECTOR vTria ;
+      if ( ! intPlStm.GetInters( ptOnL, vPnt, vBpt, vTria)) {
+         string sErr = "Error on ParPlanesStmInters at plane passing through " + ToString( vPntPlanes[i]) ;
+         LOG_ERROR( GetLogger(), sErr.c_str()) ; 
+         continue ; 
+      }                 
+
+     // inserisco il risultato nel DB
+      int nTmp{ 0} ;
+      MyAddPlaneStmIntersResultToGeomDB( pGeomDB, vPnt, vBpt, vTria, frSurf, frDest, nId, nGrpId, vtN, dToler, nTmp, nTmp, nTmp) ;       
+   }  
+
+  // restituisco l'identificativo del primo gruppo creato
+   return nFirstGrpId ;
+}
+
+//-------------------------------------------------------------------------------
+int
+ExeParPlanesSurfTmInters(  const Vector3d& vtN, const PNTVECTOR& vPnt, int nId, int nDestGrpId, int nRefType, double dToler,
+                           int* pnGrpCount)
+{
+  // eseguo
+   int nGrpCount{ 0} ;
+   int nFirstId = MyParPlanesSurfTmInters( vtN, vPnt, nId, nDestGrpId, nRefType, dToler, nGrpCount) ;
+  // aggiorno contatori
+   if ( nFirstId != GDB_ID_NULL) {
+      if ( pnGrpCount != nullptr)
+         *pnGrpCount = nGrpCount ;
+      ExeSetModified() ;
+   }
+
+  // se richiesto, salvo il comando Lua equivalente
+   if ( IsCmdLog()) {
+      string sPC ;
+      for ( size_t i = 0 ; i < vPnt.size() ; ++ i) {
+         sPC += ( i == 0 ? "{" : ",{") + ToString( vPnt[i]) + "}" ;
+      }
+      string sLua = "EgtParPlanesSurfTmInters({" + ToString( vtN) + "},{" +
+         sPC + "}," + 
+         ToString( nId) + "," +
+         ToString( nDestGrpId) + "," +
+         RefTypeToString( nRefType) + "," +
+         ToString( dToler) + ")" +
+         " -- Id=" + ToString( nFirstId) + ", GrpCnt=" + ToString( nGrpCount) ;
+      LOG_INFO( GetCmdLogger(), sLua.c_str()) ;
+   }
+
+  // restituisco l'identificativo della prima nuova entità
+   return nFirstId ;
+}
+
 //-------------------------------------------------------------------------------
 static bool
 MyChainCurvesForSurfSurfInters( const BIPNTVECTOR& vBpt, IGeomDB* pGeomDB, int nDestGrpId, int nId1, double dToler,
diff --git a/EgtExecutor.rc b/EgtExecutor.rc
index 113429a..512ac9b 100644
Binary files a/EgtExecutor.rc and b/EgtExecutor.rc differ
diff --git a/LUA_GeoInters.cpp b/LUA_GeoInters.cpp
index a9d3a1d..b3ec0d1 100644
--- a/LUA_GeoInters.cpp
+++ b/LUA_GeoInters.cpp
@@ -65,7 +65,7 @@ LuaPlaneBoxInters( lua_State* L)
    BBox3d b3Box ;
    LuaCheckParam( L, 3, b3Box)
    int nDestGrpId ;
-   LuaGetParam( L, 4, nDestGrpId) ;
+   LuaCheckParam( L, 4, nDestGrpId) ;
    int nRefType = RTY_DEFAULT ;
    LuaGetParam( L, 5, nRefType) ;
    LuaClearStack( L) ;
@@ -132,7 +132,7 @@ LuaPlaneSurfTmInters( lua_State* L)
    int nId ;
    LuaCheckParam( L, 3, nId)
    int nDestGrpId ;
-   LuaGetParam( L, 4, nDestGrpId) ;
+   LuaCheckParam( L, 4, nDestGrpId) ;
    int nRefType = RTY_DEFAULT ;
    double dToler = 20 * EPS_SMALL ;
    if ( LuaGetParam( L, 5, nRefType))
@@ -154,6 +154,36 @@ LuaPlaneSurfTmInters( lua_State* L)
    return 4 ;
 }
 
+//----------------------------------------------------------------------------
+static int
+LuaParPlanesSurfTmInters( lua_State* L)
+{
+  // 4 o 5 o 6 parametri : vtN, vPnt, nId, nDestGrpId [, nRefType] [, dToler]
+   Vector3d vtN ;
+   LuaCheckParam( L, 1, vtN)
+   PNTVECTOR vPnt ;
+   LuaCheckParam( L, 2, vPnt)
+   int nId ;
+   LuaCheckParam( L, 3, nId)
+   int nDestGrpId ;
+   LuaCheckParam( L, 4, nDestGrpId) ;
+   int nRefType = RTY_DEFAULT ;
+   double dToler = 20 * EPS_SMALL ;
+   if ( LuaGetParam( L, 5, nRefType))
+      LuaGetParam( L, 6, dToler) ;
+   LuaClearStack( L) ;
+  // eseguo l'intersezione
+   int nGrpCount = 0 ;
+   int nNewId = ExeParPlanesSurfTmInters( vtN, vPnt, nId, nDestGrpId, nRefType, dToler, &nGrpCount) ;
+  // restituisco il risultato
+   if ( nNewId != GDB_ID_NULL)
+      LuaSetParam( L, nNewId) ;
+   else
+      LuaSetParam( L) ;
+   LuaSetParam( L, nGrpCount) ;
+   return 2 ;
+}
+
 //----------------------------------------------------------------------------
 static int
 LuaSurfTmSurfTmInters( lua_State* L)
@@ -259,6 +289,7 @@ LuaInstallGeoInters( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtPlaneBoxInters", LuaPlaneBoxInters) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtLineSurfTmInters", LuaLineSurfTmInters) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtPlaneSurfTmInters", LuaPlaneSurfTmInters) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtParPlanesSurfTmInters", LuaParPlanesSurfTmInters) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSurfTmSurfTmInters", LuaSurfTmSurfTmInters) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtLineVolZmapInters", LuaLineVolZmapInters) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtPlaneVolZmapInters", LuaPlaneVolZmapInters) ;