diff --git a/EXE_GdbCreateSurf.cpp b/EXE_GdbCreateSurf.cpp
index a2e351a..33a3a0a 100644
--- a/EXE_GdbCreateSurf.cpp
+++ b/EXE_GdbCreateSurf.cpp
@@ -1373,7 +1373,7 @@ ExeCreateSurfTmByVolZmap( int nParentId, int nZmapId, int nPart)
    INTVECTOR vnModif ;
    TRIA3DEXLISTVECTOR vlTria ;
    int nCount = ( bOk ? pVZM->GetBlockCount() : 0) ;
-   ( bOk ? pVZM->GetTriangles( false, vnModif, vlTria) : false) ;
+   ( bOk ? pVZM->GetTriangles( true, vnModif, vlTria) : false) ;
    for ( int i = 0 ; i < nCount && bOk ; ++ i) {
       // se blocco non modificato, vado oltre
       if ( vnModif[i] < 0)
diff --git a/EXE_GdbModifyVol.cpp b/EXE_GdbModifyVol.cpp
index 6763100..97c1c19 100644
--- a/EXE_GdbModifyVol.cpp
+++ b/EXE_GdbModifyVol.cpp
@@ -521,3 +521,37 @@ ExeVolZmapAvoidSphere( int nId, const Point3d& ptCen, double dRad, int nRefType)
   // restituisco risultato
    return bOk ;
 }
+
+//-------------------------------------------------------------------------------
+bool
+ExeCutVolZmapPlane( int nId, const Point3d& ptOn, const Vector3d& vtN, int nRefType)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+  // recupero lo Zmap
+   IVolZmap* pVZM = GetVolZmap( pGeomDB->GetGeoObj( nId)) ;
+   bool bOk = ( pVZM != nullptr) ;
+  // recupero il riferimento locale
+   Frame3d frLoc ;
+   bOk = bOk && pGeomDB->GetGlobFrame( nId, frLoc) ;
+  // porto in locale il punto e la normale del piano
+   Point3d ptOnL = GetPointLocal( pGeomDB, ptOn, nRefType, frLoc) ;
+   Vector3d vtNL = GetVectorLocal( pGeomDB, vtN, nRefType, frLoc) ;
+  // calcolo il piano di taglio
+   Plane3d plPlane ;
+   bOk = bOk && plPlane.Set( ptOnL, vtNL) ;
+  // eseguo il taglio
+   bOk = bOk &&  pVZM->Cut( plPlane) ;
+   ExeSetModified() ;
+  // se richiesto, salvo il comando Lua equivalente
+   if ( IsCmdLog()) {
+      string sLua = "EgtCutVolZmapPlane(" + ToString( nId) + ",{" +
+                                            ToString( ptOn) + "},{" +
+                                            ToString( vtN) + "}," +
+                                            RefTypeToString( nRefType) + ")" +
+                    " -- Ok=" + ToString( bOk) ;
+      LOG_INFO( GetCmdLogger(), sLua.c_str()) ;
+   }
+  // restituisco risultato
+   return bOk ;
+}
diff --git a/EgtExecutor.rc b/EgtExecutor.rc
index 5998d27..30d97d4 100644
Binary files a/EgtExecutor.rc and b/EgtExecutor.rc differ
diff --git a/LUA_GdbModifyVol.cpp b/LUA_GdbModifyVol.cpp
index f8508dd..bb3c72f 100644
--- a/LUA_GdbModifyVol.cpp
+++ b/LUA_GdbModifyVol.cpp
@@ -383,6 +383,27 @@ LuaVolZmapAvoidSphere( lua_State* L)
    return 1 ;
 }
 
+//----------------------------------------------------------------------------
+static int
+LuaCutVolZmapPlane( lua_State* L)
+{
+  // 3 o 4 parametri : Id, ptOn, vtN [, nRefType]
+   int nId ;
+   LuaCheckParam( L, 1, nId)
+   Point3d ptOn ;
+   LuaCheckParam( L, 2, ptOn)
+   Vector3d vtN ;
+   LuaCheckParam( L, 3, vtN)
+   int nRefType = RTY_DEFAULT ;
+   LuaGetParam( L, 4, nRefType) ;
+   LuaClearStack( L) ;
+  // taglio la superficie con ilpiano
+   bool bOk = ExeCutVolZmapPlane( nId, ptOn, vtN, nRefType) ;
+  // restituisco il risultato
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
 //-------------------------------------------------------------------------------
 bool
 LuaInstallGdbModifyVol( LuaMgr& luaMgr)
@@ -402,5 +423,6 @@ LuaInstallGdbModifyVol( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtVolZmapGetDepth", LuaVolZmapGetDepth) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtVolZmapAvoidBox", LuaVolZmapAvoidBox) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtVolZmapAvoidSphere", LuaVolZmapAvoidSphere) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtCutVolZmapPlane", LuaCutVolZmapPlane) ;
    return bOk ;
 }
\ No newline at end of file