diff --git a/EXE_GdbGetSurf.cpp b/EXE_GdbGetSurf.cpp
index 967b48a..37b0736 100644
--- a/EXE_GdbGetSurf.cpp
+++ b/EXE_GdbGetSurf.cpp
@@ -592,7 +592,7 @@ ExeSurfTmFacetMinAreaRectangle( int nId, int nFacet, int nRefId, Frame3d& frRect
 
 //----------------------------------------------------------------------------
 bool
-ExeSurfTmFacetElevationInBBox( int nId, int nFacet, const BBox3d& b3Box, int nRefId, double& dElev)
+ExeSurfTmFacetElevationInBBox( int nId, int nFacet, const BBox3d& b3Box, bool bAcceptOutFacet, int nRefId, double& dElev)
 {
   // La faccia deve essere tutta contenuta nel Box
    IGeomDB* pGeomDB = GetCurrGeomDB() ;
@@ -630,10 +630,12 @@ ExeSurfTmFacetElevationInBBox( int nId, int nFacet, const BBox3d& b3Box, int nRe
    if ( vPL.empty())
       return false ;
    vPL[0].LocToLoc( frStm, frBox) ;
-  // verifico sia contenuto nella faccia
+  // se richiesto, verifico sia contenuto nella faccia
    BBox3d b3Fac ;
+   if ( ! vPL[0].GetLocalBBox( b3Fac))
+      return false ;
    BBox3d b3ExpBox = b3Box ; b3ExpBox.Expand( 100 * EPS_SMALL) ;
-   if ( ! vPL[0].GetLocalBBox( b3Fac)  ||  ! b3ExpBox.Encloses( b3Fac))
+   if ( ! bAcceptOutFacet  &&  ! b3ExpBox.Encloses( b3Fac))
       return false ;
   // calcolo elevazione massima del contorno della faccia
    const double RAY_LEN = 100000 ;
@@ -645,7 +647,7 @@ ExeSurfTmFacetElevationInBBox( int nId, int nFacet, const BBox3d& b3Box, int nRe
       IntersLineBox( ptP, vtN, RAY_LEN, b3Box, vInters, true) ;
       for ( int i = 0 ; i < int( vInters.size()) ; ++ i) {
          if ( i == 0  &&  vInters[i].first == ILBT_IN) {
-            if ( vInters[i].second > 100 * EPS_SMALL)
+            if ( ! bAcceptOutFacet  &&  vInters[i].second > 100 * EPS_SMALL)
                break ;
          }
          else if ( vInters[i].first == ILBT_OUT  ||  vInters[i].first == ILBT_TG_FIN)
diff --git a/LUA_GdbGetSurf.cpp b/LUA_GdbGetSurf.cpp
index f680f9d..8be854c 100644
--- a/LUA_GdbGetSurf.cpp
+++ b/LUA_GdbGetSurf.cpp
@@ -629,19 +629,23 @@ LuaSurfTmFacetMinAreaRectangle( lua_State* L)
 static int
 LuaSurfTmFacetElevationInBBox( lua_State* L)
 {
-  // 3 o 4 parametri : Id, nFacet, b3Box [, nRefId]
+  // 3 o 4 o 5 parametri : Id, nFacet, b3Box [, bAcceptOutFacet] [, nRefId]
    int nId ;
    LuaCheckParam( L, 1, nId)
    int nFacet ;
    LuaCheckParam( L, 2, nFacet)
    BBox3d b3Box ;
    LuaCheckParam( L, 3, b3Box)
+   bool bAcceptOutFacet = false ;
    int nRefId = nId ;
-   LuaGetParam( L, 4, nRefId) ;
+   if ( ! LuaGetParam( L, 4, nRefId)) {
+      LuaGetParam( L, 4, bAcceptOutFacet) ;
+      LuaGetParam( L, 5, nRefId) ;
+   }
    LuaClearStack( L) ;
   // calcolo elevazione
    double dElev ;
-   bool bOk = ExeSurfTmFacetElevationInBBox( nId, nFacet, b3Box, nRefId, dElev) ;
+   bool bOk = ExeSurfTmFacetElevationInBBox( nId, nFacet, b3Box, bAcceptOutFacet, nRefId, dElev) ;
    if ( bOk)
       LuaSetParam( L, dElev) ;
    else