diff --git a/EXE.h b/EXE.h
index 56f0671..fa1b90b 100644
--- a/EXE.h
+++ b/EXE.h
@@ -31,3 +31,6 @@ ILogger* GetLogger( void) ;
 ILogger* GetCmdLogger( void) ;
 bool SetCmdLog( bool bVal) ;
 bool IsCmdLog( void) ;
+
+//----------------------------------------------------------------------------
+bool ExeIsDuploBase( IGeomDB* pGeomDB, int nId) ;
diff --git a/EXE_Const.h b/EXE_Const.h
index c249b5a..fd0dcab 100644
--- a/EXE_Const.h
+++ b/EXE_Const.h
@@ -51,3 +51,6 @@ const std::string NST_SHEET_OUTREG = "SheetOut" ;
 const std::string NST_REFERENCE_REG = "RefReg" ;
 const std::string NST_DAMAGED_REG = "DmgReg" ;
 const std::string KEY_NST_OFF = "Off" ;
+
+// Per duplicati di pezzi (gruppo radice)
+const std::string DUPLO_BASE = "DuploBase" ;
diff --git a/EXE_GdbObjects.cpp b/EXE_GdbObjects.cpp
index a675d19..5113817 100644
--- a/EXE_GdbObjects.cpp
+++ b/EXE_GdbObjects.cpp
@@ -419,6 +419,22 @@ ExeErase( const INTVECTOR& vIds)
    for ( size_t i = 0 ; i < vIds.size() ; ++ i) {
       int nId = (( vIds[i] != GDB_ID_SEL) ? vIds[i] : pGeomDB->GetFirstSelectedObj()) ;
       while ( nId != GDB_ID_NULL) {
+        // se pezzo con duplicati, cancello anche questi
+         if ( ExeIsPart( nId)) {
+            INTVECTOR vnRef ;
+            pGeomDB->GetInfo( nId, GDB_SI_DUPLIST, vnRef) ;
+            for ( int nDupId : vnRef)
+               pGeomDB->Erase( nDupId) ;
+         }
+        // se altrimenti duplicato di pezzo, lo tolgo da lista duplicati nell'originale
+         else if ( ExeIsDuplo( nId)) {
+            int nOrigId ;
+            pGeomDB->GetInfo( nId, GDB_SI_DUPSOU, nOrigId) ;
+            INTVECTOR vnRef ;
+            pGeomDB->GetInfo( nOrigId, GDB_SI_DUPLIST, vnRef) ;
+            vnRef.erase( remove( vnRef.begin(), vnRef.end(), nId), vnRef.end()) ;
+            pGeomDB->SetInfo( nOrigId, GDB_SI_DUPLIST, vnRef) ;
+         }
         // cancello
          if ( ! pGeomDB->Erase( nId))
             bOk = false ;
diff --git a/EXE_GdbPartLayers.cpp b/EXE_GdbPartLayers.cpp
index 76decad..1b730cb 100644
--- a/EXE_GdbPartLayers.cpp
+++ b/EXE_GdbPartLayers.cpp
@@ -14,6 +14,7 @@
 //--------------------------- Include ----------------------------------------
 #include "stdafx.h"
 #include "EXE.h"
+#include "EXE_Const.h"
 #include "EXE_Macro.h"
 #include "/EgtDev/Include/EXeExecutor.h"
 #include "/EgtDev/Include/EgkCurve.h"
@@ -614,4 +615,204 @@ ExeSelectPathObjs( int nId, bool bHaltOnFork)
    }
   // restituisco risultato
    return bOk ;
-}
\ No newline at end of file
+}
+
+//----------------------------------------------------------------------------
+bool
+ExeIsDuploBase( IGeomDB* pGeomDB, int nId)
+{
+   if ( pGeomDB == nullptr)
+      return false ;
+   int nLevel ;
+   string sName ;
+   return ( pGeomDB->GetLevel( nId, nLevel)  &&  nLevel == GDB_LV_SYSTEM  &&
+            pGeomDB->GetName( nId, sName)  &&  sName == DUPLO_BASE) ;
+}
+
+//-----------------------------------------------------------------------------
+static int
+GetDuploBase( IGeomDB* pGeomDB, bool bCreate = false)
+{
+  // verifica collegamento a DB geometrico
+   if ( pGeomDB == nullptr)
+      return GDB_ID_NULL ;
+  // cerco il gruppo di base dei duplicati nella radice
+   int nId = pGeomDB->GetFirstGroupInGroup( GDB_ID_ROOT) ;
+   while ( nId != GDB_ID_NULL) {
+     // verifico se gruppo cercato
+      if ( ExeIsDuploBase( pGeomDB, nId))
+         return nId ;
+     // passo al successivo
+      nId = pGeomDB->GetNextGroup( nId) ;
+   }
+  // non trovato, se non richiesta creazione ritorno
+   if ( ! bCreate)
+      return GDB_ID_NULL ;
+  // devo creare il gruppo di base delle lavorazioni
+   int nDuploBaseId = pGeomDB->InsertGroup( GDB_ID_NULL, GDB_ID_ROOT, GDB_FIRST_SON, GLOB_FRM) ;
+   if ( nDuploBaseId == GDB_ID_NULL)
+      return GDB_ID_NULL ;
+  // imposto nome del gruppo
+   pGeomDB->SetName( nDuploBaseId, DUPLO_BASE) ;
+  // imposto livello del gruppo a System
+   pGeomDB->SetLevel( nDuploBaseId, GDB_LV_SYSTEM) ;
+  // imposto visualizzazione a nascosto
+   pGeomDB->SetStatus( nDuploBaseId, GDB_ST_OFF) ;
+   return nDuploBaseId ;
+}
+
+//-----------------------------------------------------------------------------
+int
+ExeDuploNew( int nSouId)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+  // Verifico sia un pezzo
+   if ( ! ExeIsPart( nSouId))
+      return GDB_ID_NULL ;
+  // Recupero il gruppo base dei duplicati
+   int nDuploBaseId = GetDuploBase( pGeomDB, true) ;
+   if ( nDuploBaseId == GDB_ID_NULL)
+      return GDB_ID_NULL ;
+  // Eseguo la copia del pezzo
+   int nNewId = pGeomDB->Copy( nSouId, GDB_ID_NULL, nDuploBaseId) ;
+   if ( nNewId == GDB_ID_NULL)
+      return GDB_ID_NULL ;
+  // Aggiorno info del sorgente
+   INTVECTOR vnRef ;
+   pGeomDB->GetInfo( nSouId, GDB_SI_DUPLIST, vnRef) ;
+   if ( find( vnRef.begin(), vnRef.end(), nNewId) == vnRef.end()) {
+      vnRef.push_back( nNewId) ;
+      pGeomDB->SetInfo( nSouId, GDB_SI_DUPLIST, vnRef) ;
+   }
+  // Aggiorno info del duplicato
+   pGeomDB->SetInfo( nNewId, GDB_SI_DUPSOU, nSouId) ;
+   pGeomDB->RemoveInfo( nNewId, GDB_SI_DUPLIST) ;
+   
+   return nNewId ;
+}
+
+//-----------------------------------------------------------------------------
+bool
+ExeDuploCount( int nSouId, int& nCount)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+  // Verifico sia un pezzo
+   if ( ! ExeIsPart( nSouId))
+      return false ;
+  // Recupero info del sorgente
+   INTVECTOR vnRef ;
+   pGeomDB->GetInfo( nSouId, GDB_SI_DUPLIST, vnRef) ;
+   nCount = int( vnRef.size()) ;
+   return true ;
+}
+
+//-----------------------------------------------------------------------------
+bool
+ExeDuploList( int nSouId, INTVECTOR& vnRef)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+  // Verifico sia un pezzo
+   if ( ! ExeIsPart( nSouId))
+      return false ;
+  // Recupero info del sorgente
+   pGeomDB->GetInfo( nSouId, GDB_SI_DUPLIST, vnRef) ;
+   return true ;
+}
+
+//-----------------------------------------------------------------------------
+bool
+ExeDuploSetModified( int nSouId)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+  // Verifico sia un pezzo
+   if ( ! ExeIsPart( nSouId))
+      return false ;
+  // Imposto il flag di modificato
+   return pGeomDB->SetInfo( nSouId, GDB_SI_DUPMODIF, true) ;
+}
+
+//-----------------------------------------------------------------------------
+bool
+ExeDuploUpdate( int nSouId)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+  // Verifico sia un pezzo
+   if ( ! ExeIsPart( nSouId))
+      return false ;
+  // Verifico se modificato da ultimo update
+   bool bModif = false ;
+   pGeomDB->GetInfo( nSouId, GDB_SI_DUPMODIF, bModif) ;
+   if ( ! bModif)
+      return true ;
+  // Recupero il gruppo base dei duplicati
+   int nDuploBaseId = GetDuploBase( pGeomDB) ;
+   if ( nDuploBaseId == GDB_ID_NULL)
+      return false ;
+  // recupero le copie
+   INTVECTOR vnRef ;
+   pGeomDB->GetInfo( nSouId, GDB_SI_DUPLIST, vnRef) ;
+  // verifico siano aggiornabili
+   bool bAllOk = true ;
+   for ( int nCopyId : vnRef) {
+      if ( pGeomDB->GetParentId( nCopyId) != nDuploBaseId)
+         bAllOk = false ;
+   }
+   if ( ! bAllOk)
+      return false ;
+  // eseguo gli aggiornamenti
+   for ( int nCopyId : vnRef) {
+      pGeomDB->Erase( nCopyId) ;
+      int nNewId = pGeomDB->Copy( nSouId, nCopyId, nDuploBaseId) ;
+      pGeomDB->SetInfo( nNewId, GDB_SI_DUPSOU, nSouId) ;
+      pGeomDB->RemoveInfo( nNewId, GDB_SI_DUPLIST) ;
+      pGeomDB->RemoveInfo( nNewId, GDB_SI_DUPMODIF) ;
+   }
+  // reset flag di modificato
+   pGeomDB->RemoveInfo( nSouId, GDB_SI_DUPMODIF) ;
+   return true ;
+}
+
+//-----------------------------------------------------------------------------
+bool
+ExeIsDuplo( int nDupId)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, false)
+  // Recupero il gruppo base dei duplicati
+   int nDuploBaseId = GetDuploBase( pGeomDB) ;
+   if ( nDuploBaseId == GDB_ID_NULL)
+      return false ;
+  // Verifico sia un duplicato (gruppo sotto quello dei duplicati con riferimento a originale)
+   if ( pGeomDB->GetGdbType( nDupId) == GDB_TY_GROUP  &&
+        pGeomDB->GetParentId( nDupId) == nDuploBaseId  &&
+        pGeomDB->ExistsInfo( nDupId, GDB_SI_DUPSOU))
+      return true ;
+   else
+      return false ;  
+}
+
+//-----------------------------------------------------------------------------
+int
+ExeDuploGetOriginal( int nDupId)
+{
+   IGeomDB* pGeomDB = GetCurrGeomDB() ;
+   VERIFY_GEOMDB( pGeomDB, GDB_ID_NULL)
+  // Recupero il gruppo base dei duplicati
+   int nDuploBaseId = GetDuploBase( pGeomDB) ;
+   if ( nDuploBaseId == GDB_ID_NULL)
+      return GDB_ID_NULL ;
+  // Verifico sia un duplicato (gruppo sotto quello dei duplicati con riferimento a originale)
+   if ( pGeomDB->GetGdbType( nDupId) != GDB_TY_GROUP  ||
+        pGeomDB->GetParentId( nDupId) != nDuploBaseId  ||
+        ! pGeomDB->ExistsInfo( nDupId, GDB_SI_DUPSOU))
+      return GDB_ID_NULL ;
+  // Recupero l'indice dell'originale
+   int nOrigId = GDB_ID_NULL ;
+   pGeomDB->GetInfo( nDupId, GDB_SI_DUPSOU, nOrigId) ;
+   return nOrigId ;
+}
diff --git a/LUA_GdbPartLayers.cpp b/LUA_GdbPartLayers.cpp
index dca84a0..3be51d9 100644
--- a/LUA_GdbPartLayers.cpp
+++ b/LUA_GdbPartLayers.cpp
@@ -401,6 +401,122 @@ LuaSelectPathObjs( lua_State* L)
    return 1 ;
 }
 
+//-------------------------------------------------------------------------------
+static int
+LuaDuploNew( lua_State* L)
+{
+  // 1 parametro : nSouId
+   int nSouId ;
+   LuaCheckParam( L, 1, nSouId)
+   LuaClearStack( L) ;
+  // creo il duplicato
+   int nNewId = ExeDuploNew( nSouId) ;
+  // restituisco il risultato
+   LuaSetParam( L, nNewId) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaDuploCount( lua_State* L)
+{
+  // 1 parametro : nSouId
+   int nSouId ;
+   LuaCheckParam( L, 1, nSouId)
+   LuaClearStack( L) ;
+  // recupero il numero di duplicati
+   int nCount ;
+   bool bOk = ExeDuploCount( nSouId, nCount) ;
+  // restituisco il risultato
+   if ( bOk)
+      LuaSetParam( L, nCount) ;
+   else
+      LuaSetParam( L) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaDuploList( lua_State* L)
+{
+  // 1 parametro : nSouId
+   int nSouId ;
+   LuaCheckParam( L, 1, nSouId)
+   LuaClearStack( L) ;
+  // recupero l'elenco dei duplicati
+   INTVECTOR vnRef ;
+   bool bOk = ExeDuploList( nSouId, vnRef) ;
+  // restituisco il risultato
+   if ( bOk)
+      LuaSetParam( L, vnRef) ;
+   else
+      LuaSetParam( L) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaDuploSetModified( lua_State* L)
+{
+  // 1 parametro : nSouId
+   int nSouId ;
+   LuaCheckParam( L, 1, nSouId)
+   LuaClearStack( L) ;
+  // dichiaro che il pezzo è modificato
+   bool bOk = ExeDuploSetModified( nSouId) ;
+  // restituisco il risultato
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaDuploUpdate( lua_State* L)
+{
+  // 1 parametro : nSouId
+   int nSouId ;
+   LuaCheckParam( L, 1, nSouId)
+   LuaClearStack( L) ;
+  // aggiorno i duplicati del pezzo
+   bool bOk = ExeDuploUpdate( nSouId) ;
+  // restituisco il risultato
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaIsDuplo( lua_State* L)
+{
+  // 1 parametro : nDouId
+   int nDouId ;
+   LuaCheckParam( L, 1, nDouId)
+   LuaClearStack( L) ;
+  // verifico se è un duplicato
+   bool bOk = ExeIsDuplo( nDouId) ;
+  // restituisco il risultato
+   LuaSetParam( L, bOk) ;
+   return 1 ;
+}
+
+//-------------------------------------------------------------------------------
+static int
+LuaDuploGetOriginal( lua_State* L)
+{
+  // 1 parametro : nDouId
+   int nDouId ;
+   LuaCheckParam( L, 1, nDouId)
+   LuaClearStack( L) ;
+  // verifico se è un duplicato
+   int nOrigId = ExeDuploGetOriginal( nDouId) ;
+  // restituisco il risultato
+   if ( nOrigId != GDB_ID_NULL)
+      LuaSetParam( L, nOrigId) ;
+   else
+      LuaSetParam( L) ;
+   return 1 ;
+}
+
 //-------------------------------------------------------------------------------
 bool
 LuaInstallGdbPartLayer( LuaMgr& luaMgr)
@@ -429,5 +545,12 @@ LuaInstallGdbPartLayer( LuaMgr& luaMgr)
    bOk = bOk && luaMgr.RegisterFunction( "EgtSelectLayerObjs", LuaSelectLayerObjs) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtDeselectLayerObjs", LuaDeselectLayerObjs) ;
    bOk = bOk && luaMgr.RegisterFunction( "EgtSelectPathObjs", LuaSelectPathObjs) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploNew", LuaDuploNew) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploCount", LuaDuploCount) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploList", LuaDuploList) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploSetModified", LuaDuploSetModified) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploUpdate", LuaDuploUpdate) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtIsDuplo", LuaIsDuplo) ;
+   bOk = bOk && luaMgr.RegisterFunction( "EgtDuploGetOriginal", LuaDuploGetOriginal) ;
    return bOk ;
 }