diff --git a/Attribs.cpp b/Attribs.cpp
index 898605f..b77cb4a 100644
--- a/Attribs.cpp
+++ b/Attribs.cpp
@@ -95,26 +95,36 @@ bool
 Attribs::Save( NgeWriter& ngeOut) const
 {
   // flag presenza attributi
-   ngeOut.WriteKey( NGE_A) ;
+   if ( ! ngeOut.WriteKey( NGE_A))
+      return false ;
   // livello
-   ngeOut.WriteUchar( m_Data[LEVEL], ",") ;
+   if ( ! ngeOut.WriteUchar( m_Data[LEVEL], ","))
+      return false ;
   // modo
-   ngeOut.WriteUchar( m_Data[MODE], ",") ;
+   if ( ! ngeOut.WriteUchar( m_Data[MODE], ","))
+      return false ;
   // stato (se SEL è convertito in ON)
    int nStat = (( m_Data[STATUS] > GDB_ST_ON) ? GDB_ST_ON : m_Data[STATUS]) ;
-   ngeOut.WriteUchar( nStat, ",") ;
+   if ( ! ngeOut.WriteUchar( nStat, ","))
+      return false ;
   // marcatura (sempre OFF)
-   ngeOut.WriteUchar( GDB_MK_OFF, ";") ;
+   if ( ! ngeOut.WriteUchar( GDB_MK_OFF, ";"))
+      return false ;
   // materiale
-   ngeOut.WriteInt( m_Material, ";") ;
+   if ( ! ngeOut.WriteInt( m_Material, ";"))
+      return false ;
   // colore
-   ngeOut.WriteCol( m_Color, ";") ;
+   if ( ! ngeOut.WriteCol( m_Color, ";"))
+      return false ;
   // numero di stringhe di info (nelle linee successive)
-   ngeOut.WriteInt( int( m_slInfo.size()), ";", true) ;
+   if ( ! ngeOut.WriteInt( int( m_slInfo.size()), ";", true))
+      return false ;
   // stringhe di info
    STRLIST::const_iterator iIter ;
-   for ( iIter = m_slInfo.begin() ; iIter != m_slInfo.end() ; ++ iIter)
-      ngeOut.WriteString( *iIter, nullptr, true) ;
+   for ( iIter = m_slInfo.begin() ; iIter != m_slInfo.end() ; ++ iIter) {
+      if ( ! ngeOut.WriteString( *iIter, nullptr, true))
+         return false ;
+   }
 
    return true ;
 }
diff --git a/CurveArc.cpp b/CurveArc.cpp
index 48f9282..e58d17a 100644
--- a/CurveArc.cpp
+++ b/CurveArc.cpp
@@ -487,17 +487,23 @@ bool
 CurveArc::Save( NgeWriter& ngeOut) const
 {
   // centro
-   ngeOut.WritePoint( m_PtCen, ";") ;
+   if ( ! ngeOut.WritePoint( m_PtCen, ";"))
+      return false ;
   // versore Normale
-   ngeOut.WriteVector( m_VtN, ";") ; 
+   if ( ! ngeOut.WriteVector( m_VtN, ";"))
+      return false ;
   // raggio
-   ngeOut.WriteDouble( m_dRad, ";") ;
+   if ( ! ngeOut.WriteDouble( m_dRad, ";"))
+      return false ;
   // versore Iniziale
-   ngeOut.WriteVector( m_VtS, ";") ; 
+   if ( ! ngeOut.WriteVector( m_VtS, ";"))
+      return false ;
   // angolo al centro
-   ngeOut.WriteDouble( m_dAngCenDeg, ";") ;
+   if ( ! ngeOut.WriteDouble( m_dAngCenDeg, ";"))
+      return false ;
   // deltaN
-   ngeOut.WriteDouble( m_dDeltaN, ";", true) ;
+   if ( ! ngeOut.WriteDouble( m_dDeltaN, ";", true))
+      return false ;
 
    return true ;
 }
diff --git a/CurveBezier.cpp b/CurveBezier.cpp
index 5644ade..74f9148 100644
--- a/CurveBezier.cpp
+++ b/CurveBezier.cpp
@@ -352,15 +352,21 @@ bool
 CurveBezier::Save( NgeWriter& ngeOut) const
 {
   // flag razionale
-   ngeOut.WriteBool( m_bRat, ";") ;
+   if ( ! ngeOut.WriteBool( m_bRat, ";"))
+      return false ;
   // grado
-   ngeOut.WriteInt( m_nDeg, ";", true) ;
+   if ( ! ngeOut.WriteInt( m_nDeg, ";", true))
+      return false ;
   // ciclo sui punti di controllo ( con pesi se razionale)
    for ( int i = 0 ; i <= m_nDeg ; ++ i) {
-      if ( ! m_bRat)
-         ngeOut.WritePoint( m_aPtCtrl[i], ";", true) ;
-      else
-         ngeOut.WritePointW( m_aPtCtrl[i], m_aWeCtrl[i], ";", true) ;
+      if ( ! m_bRat) {
+         if ( ! ngeOut.WritePoint( m_aPtCtrl[i], ";", true))
+            return false ;
+      }
+      else {
+         if ( ! ngeOut.WritePointW( m_aPtCtrl[i], m_aWeCtrl[i], ";", true))
+            return false ;
+      }
    }
 
    return true ;
diff --git a/CurveComposite.cpp b/CurveComposite.cpp
index 2a6189e..11a3314 100644
--- a/CurveComposite.cpp
+++ b/CurveComposite.cpp
@@ -411,7 +411,8 @@ bool
 CurveComposite::Save( NgeWriter& ngeOut) const
 {
   // numero di curve
-   ngeOut.WriteInt( m_nCounter, nullptr, true) ;
+   if ( ! ngeOut.WriteInt( m_nCounter, nullptr, true))
+      return false ;
   // ciclo sulle curve componenti
    int i = 0 ;
    const ICurve* pCrvSmpl = GetFirstCurve() ;
@@ -421,10 +422,12 @@ CurveComposite::Save( NgeWriter& ngeOut) const
       if ( pCSmplRW == nullptr)
          return false ;
      // emetto tipo della curva semplice
-      ngeOut.WriteKey( pCSmplRW->GetNgeId()) ;
+      if ( ! ngeOut.WriteKey( pCSmplRW->GetNgeId()))
+         return false ;
      // assegno ed emetto nome della curva semplice
       string sCrvName = "#" + ToString( ++i) ;
-      ngeOut.WriteString( sCrvName, nullptr, true) ;
+      if ( ! ngeOut.WriteString( sCrvName, nullptr, true))
+         return false ;
      // salvataggio della curva semplice
       if ( ! pCSmplRW->Save( ngeOut))
          return false ;
diff --git a/CurveLine.cpp b/CurveLine.cpp
index 3cecb6c..019c056 100644
--- a/CurveLine.cpp
+++ b/CurveLine.cpp
@@ -165,8 +165,10 @@ bool
 CurveLine::Save( NgeWriter& ngeOut) const
 {
   // parametri : punti iniziale e finale
-   ngeOut.WritePoint( m_PtStart, ";") ;
-   ngeOut.WritePoint( m_PtEnd, ";", true) ;
+   if ( ! ngeOut.WritePoint( m_PtStart, ";"))
+      return false ;
+   if ( ! ngeOut.WritePoint( m_PtEnd, ";", true))
+      return false ;
 
    return true ;
 }
diff --git a/EgtGeomKernel.rc b/EgtGeomKernel.rc
index 73a0e96..d36b9fc 100644
Binary files a/EgtGeomKernel.rc and b/EgtGeomKernel.rc differ
diff --git a/EgtGeomKernel.vcxproj b/EgtGeomKernel.vcxproj
index bae4925..a80881c 100644
--- a/EgtGeomKernel.vcxproj
+++ b/EgtGeomKernel.vcxproj
@@ -165,6 +165,7 @@ copy $(TargetPath) \EgtProg\Dll64</Command>
       <OpenMPSupport>true</OpenMPSupport>
       <CompileAs>CompileAsCpp</CompileAs>
       <FavorSizeOrSpeed>Speed</FavorSizeOrSpeed>
+      <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>
     <Link>
       <SubSystem>Windows</SubSystem>
@@ -200,6 +201,7 @@ copy $(TargetPath) \EgtProg\Dll32</Command>
       <OpenMPSupport>true</OpenMPSupport>
       <CompileAs>CompileAsCpp</CompileAs>
       <FavorSizeOrSpeed>Speed</FavorSizeOrSpeed>
+      <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>
     <Link>
       <SubSystem>Windows</SubSystem>
diff --git a/EgtGeomKernel.vcxproj.filters b/EgtGeomKernel.vcxproj.filters
index 338ca4c..1c40fce 100644
--- a/EgtGeomKernel.vcxproj.filters
+++ b/EgtGeomKernel.vcxproj.filters
@@ -34,6 +34,9 @@
     <Filter Include="File di origine\GeoDist">
       <UniqueIdentifier>{cc84f71a-b149-4187-af26-736133e92672}</UniqueIdentifier>
     </Filter>
+    <Filter Include="File di origine\GeoInters">
+      <UniqueIdentifier>{7284f71c-3fd5-4bb9-bfe6-2c8c312985cc}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="Vector3d.cpp">
diff --git a/ExtText.cpp b/ExtText.cpp
index 40d22cd..6a6b5e2 100644
--- a/ExtText.cpp
+++ b/ExtText.cpp
@@ -220,27 +220,38 @@ bool
 ExtText::Save( NgeWriter& ngeOut) const
 {
   // punto di inserimento
-   ngeOut.WritePoint( m_ptP, ";") ;
+   if ( ! ngeOut.WritePoint( m_ptP, ";"))
+      return false ;
   // flag posizione inserimento
-   ngeOut.WriteInt( m_nInsPos, ";") ;
+   if ( ! ngeOut.WriteInt( m_nInsPos, ";"))
+      return false ;
   // versore normale
-   ngeOut.WriteVector( m_vtN, ";") ;
+   if ( ! ngeOut.WriteVector( m_vtN, ";"))
+      return false ;
   // versore di direzione
-   ngeOut.WriteVector( m_vtD, ";", true) ;
+   if ( ! ngeOut.WriteVector( m_vtD, ";", true))
+      return false ;
   // testo
-   ngeOut.WriteString( m_sText, nullptr, true) ;
+   if ( ! ngeOut.WriteString( m_sText, nullptr, true))
+      return false ;
   // font
-   ngeOut.WriteString( m_sFont, ";") ;
+   if ( ! ngeOut.WriteString( m_sFont, ";"))
+      return false ;
   // spessore del font
-   ngeOut.WriteInt( m_nWeight, ",") ;
+   if ( ! ngeOut.WriteInt( m_nWeight, ","))
+      return false ;
   // flag di italico
-   ngeOut.WriteBool( m_bItalic, ",") ;
+   if ( ! ngeOut.WriteBool( m_bItalic, ","))
+      return false ;
   // altezza del font
-   ngeOut.WriteDouble( m_dHeight, ",") ;
+   if ( ! ngeOut.WriteDouble( m_dHeight, ","))
+      return false ;
   // rapporto larghezza su altezza del font
-   ngeOut.WriteDouble( m_dRatio, ",") ;
+   if ( ! ngeOut.WriteDouble( m_dRatio, ","))
+      return false ;
   // avanzamento addizionale tra caratteri
-   ngeOut.WriteDouble( m_dAddAdvance, ";", true) ;
+   if ( ! ngeOut.WriteDouble( m_dAddAdvance, ";", true))
+      return false ;
   
    return true ;
 }
diff --git a/GdbExecutor.cpp b/GdbExecutor.cpp
index d74be6b..aebf250 100644
--- a/GdbExecutor.cpp
+++ b/GdbExecutor.cpp
@@ -4313,14 +4313,17 @@ GdbExecutor::ExecuteSave( const string& sCmd2, const STRVECTOR& vsParams)
    string sFile = vsParams[0] ;
    m_pParser->DirReplace( sFile) ;
   // il secondo parametro, opzionale, indica il formato del file
-   bool bBinary = false ;
+   int nFlag = GDB_SV_CMPTXT ;
    if ( vsParams.size() == 2) {
-      string sBinary = vsParams[1] ;
-      ToUpper( sBinary) ;
-      bBinary = ( sBinary == "B"  ||  sBinary == "BINARY") ;
+      string sFlag = vsParams[1] ;
+      ToUpper( sFlag) ;
+      if ( sFlag == "T"  ||  sFlag == "TEXT")
+         nFlag = GDB_SV_TXT ;
+      else if ( sFlag == "B"  ||  sFlag == "BINARY")
+         nFlag = GDB_SV_BIN ;
    }
   // esecuzione salvataggio
-   return m_pGDB->Save( sFile, bBinary) ;
+   return m_pGDB->Save( sFile, nFlag) ;
 }
 
 //----------------------------------------------------------------------------
diff --git a/GdbGeo.cpp b/GdbGeo.cpp
index 6c37f56..8696d9e 100644
--- a/GdbGeo.cpp
+++ b/GdbGeo.cpp
@@ -93,16 +93,20 @@ GdbGeo::Save( NgeWriter& ngeOut) const
       return false ;
 
   // tipo entità e identificativi
-   ngeOut.WriteKey( pGObjRW->GetNgeId()) ;
-   ngeOut.WriteInt( m_nId, "@") ;
-   ngeOut.WriteInt( GetParentId(), nullptr, true) ;
+   if ( ! ngeOut.WriteKey( pGObjRW->GetNgeId()))
+      return false ;
+   if ( ! ngeOut.WriteInt( m_nId, "@"))
+      return false ;
+   if ( ! ngeOut.WriteInt( GetParentId(), nullptr, true))
+      return false ;
 
   // attributi
    if ( ! GdbObj::SaveAttribs( ngeOut))
       return false ;
 
   // parametri geometrici
-   ngeOut.WriteKey( NGE_G) ;
+   if ( ! ngeOut.WriteKey( NGE_G))
+      return false ;
    return pGObjRW->Save( ngeOut) ;
 }
 
diff --git a/GdbGroup.cpp b/GdbGroup.cpp
index 24c8278..c26b5d2 100644
--- a/GdbGroup.cpp
+++ b/GdbGroup.cpp
@@ -105,34 +105,37 @@ GdbGroup::Clone( int nId, IdManager& IdMgr) const
 bool
 GdbGroup::Save( NgeWriter& ngeOut) const
 {
-   bool bOk = true ;
-
   // tipo entità e identificativi
-   ngeOut.WriteKey( NGE_A_GRP) ;
-   ngeOut.WriteInt( m_nId, "@") ;
-   ngeOut.WriteInt( GetParentId(), nullptr, true) ;
+   if ( ! ngeOut.WriteKey( NGE_A_GRP))
+      return false ;
+   if ( ! ngeOut.WriteInt( m_nId, "@"))
+      return false ;
+   if ( ! ngeOut.WriteInt( GetParentId(), nullptr, true))
+      return false ;
 
   // attributi
    if ( ! GdbObj::SaveAttribs( ngeOut))
-      bOk = false ;
+      return false ;
 
   // dati geometrici
-   ngeOut.WriteKey( NGE_G) ;
+   if ( ! ngeOut.WriteKey( NGE_G))
+      return false ;
    // puntatore alla prima copia (per ora NULL)
-   ngeOut.WriteInt( GDB_ID_NULL, nullptr, true) ;
+   if ( ! ngeOut.WriteInt( GDB_ID_NULL, nullptr, true))
+      return false ;
    // frame
    if ( ! m_gfrFrame.Save( ngeOut))
-      bOk = false ;
+      return false ;
 
   // salvataggio dei figli
    const GdbObj* pGdbObj = GetFirstObj() ;
    while ( pGdbObj != nullptr) {
       if ( ! pGdbObj->Save( ngeOut))
-         bOk = false ;
+         return false ;
       pGdbObj = pGdbObj->GetNext() ;
    }
 
-   return bOk ;
+   return true ;
 }
 
 //----------------------------------------------------------------------------
diff --git a/GdbMaterialMgr.cpp b/GdbMaterialMgr.cpp
index dd4d7d2..bbd5679 100644
--- a/GdbMaterialMgr.cpp
+++ b/GdbMaterialMgr.cpp
@@ -49,22 +49,31 @@ bool
 GdbMaterialMgr::Save( NgeWriter& ngeOut) const
 {
   // intestazione libreria
-   ngeOut.WriteKey( NGE_MAT_LIB) ;
+   if ( ! ngeOut.WriteKey( NGE_MAT_LIB))
+      return false ;
   // numero di materiali custom
    int nCustNum = int( m_GdbMats.size()) - m_nStdNum ;
-   ngeOut.WriteInt( nCustNum, ";", true) ;
+   if ( ! ngeOut.WriteInt( nCustNum, ";", true))
+      return false ;
   // scrittura dei materiali custom
    for ( int i = m_nStdNum ; i < int( m_GdbMats.size()) ; ++ i) {
      // Nome, Id, Tipo (1=materiale senza texture)
       string sMatName = ( m_GdbMats[i].sName.empty() ? "$$" : m_GdbMats[i].sName) ;
-      ngeOut.WriteString( sMatName, ",") ;
-      ngeOut.WriteInt( i + 1, ",") ;
-      ngeOut.WriteInt( 1, ";", true) ;
+      if ( ! ngeOut.WriteString( sMatName, ","))
+         return false ;
+      if ( ! ngeOut.WriteInt( i + 1, ","))
+         return false ;
+      if ( ! ngeOut.WriteInt( 1, ";", true))
+         return false ;
      // dati del materiale
-      ngeOut.WriteCol( m_GdbMats[i].matM.GetAmbient(), ";") ;
-      ngeOut.WriteCol( m_GdbMats[i].matM.GetDiffuse(), ";") ;
-      ngeOut.WriteCol( m_GdbMats[i].matM.GetSpecular(), ";") ;
-      ngeOut.WriteDouble( m_GdbMats[i].matM.GetShininess(), ";", true, 1) ;
+      if ( ! ngeOut.WriteCol( m_GdbMats[i].matM.GetAmbient(), ";"))
+         return false ;
+      if ( ! ngeOut.WriteCol( m_GdbMats[i].matM.GetDiffuse(), ";"))
+         return false ;
+      if ( ! ngeOut.WriteCol( m_GdbMats[i].matM.GetSpecular(), ";"))
+         return false ;
+      if ( ! ngeOut.WriteDouble( m_GdbMats[i].matM.GetShininess(), ";", true, 1))
+         return false ;
    }
 
    return true ;
diff --git a/GeoFrame3d.cpp b/GeoFrame3d.cpp
index 3735f66..379db60 100644
--- a/GeoFrame3d.cpp
+++ b/GeoFrame3d.cpp
@@ -153,9 +153,7 @@ GeoFrame3d::GetNgeId( void) const
 bool
 GeoFrame3d::Save( NgeWriter& ngeOut) const
 {
-   ngeOut.WriteFrame( m_frF, ";", true) ;
-
-   return true ;
+   return ngeOut.WriteFrame( m_frF, ";", true) ;
 }
 
 //----------------------------------------------------------------------------
diff --git a/GeoPoint3d.cpp b/GeoPoint3d.cpp
index 121f175..b0939ea 100644
--- a/GeoPoint3d.cpp
+++ b/GeoPoint3d.cpp
@@ -121,9 +121,7 @@ bool
 GeoPoint3d::Save( NgeWriter& ngeOut) const
 {
   // parametri : punto
-   ngeOut.WritePoint( m_ptP, ";", true) ;
-
-   return true ;
+   return ngeOut.WritePoint( m_ptP, ";", true) ;
 }
 
 //----------------------------------------------------------------------------
diff --git a/GeoVector3d.cpp b/GeoVector3d.cpp
index 58a8518..d6ee141 100644
--- a/GeoVector3d.cpp
+++ b/GeoVector3d.cpp
@@ -138,8 +138,10 @@ bool
 GeoVector3d::Save( NgeWriter& ngeOut) const
 {
   // parametri : vettore
-   ngeOut.WriteVector( m_vtV, ";") ;
-   ngeOut.WritePoint( m_ptBase, ";", true) ;
+   if ( ! ngeOut.WriteVector( m_vtV, ";"))
+      return false ;
+   if ( ! ngeOut.WritePoint( m_ptBase, ";", true))
+      return false ;
 
    return true ;
 }
diff --git a/GeomDB.cpp b/GeomDB.cpp
index 850fb3a..e636afb 100644
--- a/GeomDB.cpp
+++ b/GeomDB.cpp
@@ -194,11 +194,11 @@ GeomDB::LoadOneObj( NgeReader& ngeIn, bool& bEnd)
 
 //----------------------------------------------------------------------------
 bool
-GeomDB::Save( const std::string& sFileOut, bool bBinary) const
+GeomDB::Save( const std::string& sFileOut, int nFlag) const
 {
   // apertura file
    NgeWriter ngeOut ;
-   if ( ! ngeOut.Init( sFileOut, bBinary)) {
+   if ( ! ngeOut.Init( sFileOut, nFlag)) {
       LOG_ERROR( GetEGkLogger(), "GeomDbSave : Error on Init ")
       return false ;
    }
@@ -242,17 +242,24 @@ bool
 GeomDB::SaveHeader( NgeWriter& ngeOut) const
 {
   // intestazione
-   ngeOut.WriteKey( NGE_START) ;
-   ngeOut.WriteString( NGE_GEOMDB, ",") ;
-   ngeOut.WriteInt( NGE_MAJOR_VER, ".") ;
-   ngeOut.WriteInt( NGE_MINOR_VER, ".") ;
-   ngeOut.WriteInt( NGE_PATCH_VER, ";", true) ;
+   if ( ! ngeOut.WriteKey( NGE_START))
+      return false ;
+   if ( ! ngeOut.WriteString( NGE_GEOMDB, ","))
+      return false ;
+   if ( ! ngeOut.WriteInt( NGE_MAJOR_VER, "."))
+      return false ;
+   if ( ! ngeOut.WriteInt( NGE_MINOR_VER, "."))
+      return false ;
+   if ( ! ngeOut.WriteInt( NGE_PATCH_VER, ";", true))
+      return false ;
 
   // materiale di default come colore
    Color colDef( 0, 0, 0, 0) ;
    GetDefaultMaterial( colDef) ;
-   ngeOut.WriteKey( NGE_MAT_DEF) ;
-   ngeOut.WriteCol( colDef, ";", true) ;
+   if ( ! ngeOut.WriteKey( NGE_MAT_DEF))
+      return false ;
+   if ( ! ngeOut.WriteCol( colDef, ";", true))
+      return false ;
 
    return true ;
 }
@@ -262,9 +269,7 @@ bool
 GeomDB::SaveFooter( NgeWriter& ngeOut) const
 {
   // terminazione
-   ngeOut.WriteKey( NGE_END) ;
-
-   return true ;
+   return ngeOut.WriteKey( NGE_END) ;
 }
 
 //----------------------------------------------------------------------------
diff --git a/GeomDB.h b/GeomDB.h
index 8401478..2c7d68f 100644
--- a/GeomDB.h
+++ b/GeomDB.h
@@ -32,7 +32,7 @@ class GeomDB : public IGeomDB
       virtual bool Init( void) ;
       virtual bool Clear( void) ;
       virtual bool Load( const std::string& sFileIn) ;
-      virtual bool Save( const std::string& sFileOut, bool bBinary = true) const ;
+      virtual bool Save( const std::string& sFileOut, int nFlag = GDB_SV_BIN) const ;
       virtual bool ExistsObj( int nId) const ;
       virtual int  AddGroup( int nId, int nParentId, const Frame3d& frFrame) ;
       virtual int  InsertGroup( int nId, int nRefId, int nSonBeforeAfter, const Frame3d& frFrame) ;
diff --git a/NgeReader.cpp b/NgeReader.cpp
index 1cd03b0..8c8cb20 100644
--- a/NgeReader.cpp
+++ b/NgeReader.cpp
@@ -73,6 +73,10 @@ NgeReader::NgeType( const std::string& sFile)
   // chiusura del file
    InFile.close() ;
 
+  // verifico se file compresso (gz)
+   if ( cBuff[0] == '\x1F'  &&  cBuff[1] == '\x8B')
+      return NGE_ASCII ;
+
   // verifico se iniziano con "START"
    string sBuff = cBuff ;
    size_t nPos = sBuff.find( "START") ;
diff --git a/NgeWriter.cpp b/NgeWriter.cpp
index 265291d..aea533c 100644
--- a/NgeWriter.cpp
+++ b/NgeWriter.cpp
@@ -15,246 +15,262 @@
 #include "stdafx.h"
 #include "NgeWriter.h"
 #include "NgeKeyW.h"
+#include "/EgtDev/Include/EGkGdbConst.h"
 #include "/EgtDev/Include/EGkStringUtils3d.h"
 #include "/EgtDev/Include/EgnStringConverter.h"
+#include "/EgtDev/Extern/Zlib/Include/zlib.h"
 
 using namespace std ;
 
+//----------------------------------------------------------------------------
+inline bool
+WriteStringOutTxt( gzFile OutTxtFile, const char* szVal, const char* szSep, bool bEndL)
+{
+  // verifico apertura file
+   if ( OutTxtFile == nullptr)
+      return false ;
+  // scrivo stringa
+   if ( gzputs( OutTxtFile, szVal) == Z_ERRNO)
+      return false ;
+  // se fornito, scrivo separatore
+   if ( szSep != nullptr  &&  szSep[0] != '\0') {
+      if ( gzputs( OutTxtFile, szSep) == Z_ERRNO)
+         return false ;
+   }
+  // se richiesto, scrivo fine linea
+   if ( bEndL) {
+      if ( gzputs( OutTxtFile, "\r\n") == Z_ERRNO)
+         return false ;
+   }
+   return true ;
+}
+
 //----------------------------------------------------------------------------
 bool
-NgeWriter::Init( const std::string& sFileOut, bool bBinary) 
+NgeWriter::Init( const string& sFileOut, int nFlag) 
 {
   // salvo tipo file
-   m_bBinary = bBinary ;
+   m_bBinary = ( nFlag == GDB_SV_BIN) ;
 
   // apertura del file di uscita
-   ios_base::openmode nMode = ios::out | ( m_bBinary ? ios::binary : 0) ;
-   int nProt = _SH_DENYWR ;
-   m_OutFile.open( stringtoW( sFileOut), nMode, nProt) ;
-   return m_OutFile.good() ;
+   if ( m_bBinary) {
+      ios_base::openmode nMode = ios::out | ( m_bBinary ? ios::binary : 0) ;
+      int nProt = _SH_DENYWR ;
+      m_OutBinFile.open( stringtoW( sFileOut), nMode, nProt) ;
+      return m_OutBinFile.good() ;
+   }
+   else {
+      if ( nFlag == GDB_SV_TXT)
+         m_OutTxtFile = gzopen_w( stringtoW( sFileOut), "wbT") ;
+      else       // GDB_SV_CMPTXT
+         m_OutTxtFile = gzopen_w( stringtoW( sFileOut), "wb") ;
+      if ( m_OutTxtFile == nullptr)
+         return false ;
+      const int DIM_BUFFER = 65536 ;
+      if ( gzbuffer( m_OutTxtFile, DIM_BUFFER) != Z_OK)
+         return false ;
+      const int COMPR_LEVEL = 3 ;    // 0 = no compression ... 9 = max compression
+      if ( gzsetparams( m_OutTxtFile, COMPR_LEVEL, Z_DEFAULT_STRATEGY) != Z_OK)
+         return false ;
+      return true ;
+   }
 }
 
 //----------------------------------------------------------------------------
 bool
 NgeWriter::Close( void) 
 {
-   bool bOk = ( m_OutFile.good()  &&  m_OutFile.is_open()) ;
-
-   if ( m_OutFile.is_open())
-      m_OutFile.close() ;
-
-   return bOk ;
+   if ( m_bBinary) {
+      bool bOk = ( m_OutBinFile.good()  &&  m_OutBinFile.is_open()) ;
+      if ( m_OutBinFile.is_open())
+         m_OutBinFile.close() ;
+      return bOk ;
+   }
+   else {
+      if ( m_OutTxtFile != nullptr) {
+         bool bOk = ( gzclose( m_OutTxtFile) == Z_OK) ;
+         m_OutTxtFile = nullptr ;
+         return bOk ;
+      }
+      return true ;
+   }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteUchar( unsigned char ucVal, const char* szSep, bool bEndL)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &ucVal, sizeof( ucVal)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &ucVal, sizeof( ucVal)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << ToString( ucVal) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( ucVal).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteBool( bool bVal, const char* szSep, bool bEndL)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &bVal, sizeof( bVal)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &bVal, sizeof( bVal)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << ToString( bVal) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( bVal).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteInt( int nVal, const char* szSep, bool bEndL)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &nVal, sizeof( nVal)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &nVal, sizeof( nVal)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << ToString( nVal) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( nVal).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteDouble( double dVal, const char* szSep, bool bEndL, int nPrec)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &dVal, sizeof( dVal)) ;
-   else {
-      m_OutFile << ToString( dVal, nPrec) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
-   }
-}
-
-//----------------------------------------------------------------------------
-void
-NgeWriter::WriteString( const std::string& sVal, const char* szSep, bool bEndL)
-{
-   if ( ! m_OutFile.is_open())
-      return ;
-
    if ( m_bBinary) {
-      int nDim = int( sVal.size()) ; 
-      m_OutFile.write( (char*) &nDim, sizeof( nDim)) ;
-      m_OutFile.write( sVal.c_str(), sVal.size()) ;
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &dVal, sizeof( dVal)) ;
+      return m_OutBinFile.good() ;
    }
    else {
-      m_OutFile << sVal ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( dVal, nPrec).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
+NgeWriter::WriteString( const string& sVal, const char* szSep, bool bEndL)
+{
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      int nDim = int( sVal.size()) ; 
+      m_OutBinFile.write( (char*) &nDim, sizeof( nDim)) ;
+      m_OutBinFile.write( sVal.c_str(), sVal.size()) ;
+      return m_OutBinFile.good() ;
+   }
+   else {
+      return WriteStringOutTxt( m_OutTxtFile, sVal.c_str(), szSep, bEndL) ;
+   }
+}
+
+//----------------------------------------------------------------------------
+bool
 NgeWriter::WriteVector( const Vector3d& vtV, const char* szSep, bool bEndL, int nPrec)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &vtV.v, sizeof( vtV.v)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &vtV.v, sizeof( vtV.v)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << ToString( vtV, nPrec) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( vtV, nPrec).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WritePoint( const Point3d& ptP, const char* szSep, bool bEndL, int nPrec)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &ptP.v, sizeof( ptP.v)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &ptP.v, sizeof( ptP.v)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << ToString( ptP, nPrec) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( ptP, nPrec).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WritePointW( const Point3d& ptP, double dW, const char* szSep, bool bEndL, int nPrecP, int nPrecW)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
    if ( m_bBinary) {
-      m_OutFile.write( (char*) &ptP.v, sizeof( ptP.v)) ;
-      m_OutFile.write( (char*) &dW, sizeof( dW)) ;
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &ptP.v, sizeof( ptP.v)) ;
+      m_OutBinFile.write( (char*) &dW, sizeof( dW)) ;
+      return m_OutBinFile.good() ;
    }
    else {
-      m_OutFile << ToString( ptP, dW, nPrecP, nPrecW) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( ptP, dW, nPrecP, nPrecW).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteFrame( const Frame3d& frF, const char* szSep, bool bEndL, int nPrecP, int nPrecV)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
    if ( m_bBinary) {
-      m_OutFile.write( (char*) &frF.Orig().v, sizeof( frF.Orig().v)) ;
-      m_OutFile.write( (char*) &frF.VersX().v, sizeof( frF.VersX().v)) ;
-      m_OutFile.write( (char*) &frF.VersY().v, sizeof( frF.VersY().v)) ;
-      m_OutFile.write( (char*) &frF.VersZ().v, sizeof( frF.VersZ().v)) ;
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &frF.Orig().v, sizeof( frF.Orig().v)) ;
+      m_OutBinFile.write( (char*) &frF.VersX().v, sizeof( frF.VersX().v)) ;
+      m_OutBinFile.write( (char*) &frF.VersY().v, sizeof( frF.VersY().v)) ;
+      m_OutBinFile.write( (char*) &frF.VersZ().v, sizeof( frF.VersZ().v)) ;
+      return m_OutBinFile.good() ;
    }
    else {
-      m_OutFile << ToString( frF, nPrecP, nPrecV) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( frF, nPrecP, nPrecV).c_str(), szSep, bEndL) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteKey( int nKey)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
    if ( nKey < 0  ||  nKey > NGE_LAST_ID)
-      return ;
+      return false ;
 
-   if ( m_bBinary)
-      m_OutFile.write( (char*) &NgeBinKeyW[nKey], sizeof( int)) ;
+   if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
+      m_OutBinFile.write( (char*) &NgeBinKeyW[nKey], sizeof( int)) ;
+      return m_OutBinFile.good() ;
+   }
    else {
-      m_OutFile << NgeAscKeyW[nKey] ;
-      m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, NgeAscKeyW[nKey].c_str(), nullptr, true) ;
    }
 }
 
 //----------------------------------------------------------------------------
-void
+bool
 NgeWriter::WriteCol( const Color& cCol, const char* szSep, bool bEndL)
 {
-   if ( ! m_OutFile.is_open())
-      return ;
-
    if ( m_bBinary) {
+      if ( ! m_OutBinFile.is_open())
+         return false ;
       unsigned char ucCol[4] ;
       ucCol[0] = cCol.GetIntRed() ;
       ucCol[1] = cCol.GetIntGreen() ;
       ucCol[2] = cCol.GetIntBlue() ;
       ucCol[3] = cCol.GetIntAlpha() ;
-      m_OutFile.write( (char*) ucCol, sizeof( ucCol)) ;
+      m_OutBinFile.write( (char*) ucCol, sizeof( ucCol)) ;
+      return m_OutBinFile.good() ;
    }
    else {
-      m_OutFile << ToString( cCol) ;
-      if ( szSep != nullptr)
-         m_OutFile << szSep ;
-      if ( bEndL)
-         m_OutFile << endl ;
+      return WriteStringOutTxt( m_OutTxtFile, ToString( cCol).c_str(), szSep, bEndL) ;
    }
 }
diff --git a/NgeWriter.h b/NgeWriter.h
index bd617fb..f906385 100644
--- a/NgeWriter.h
+++ b/NgeWriter.h
@@ -18,29 +18,34 @@
 #include "/EgtDev/Include/EGkColor.h"
 #include <fstream>
 
+struct gzFile_s ;
+
 //----------------------------------------------------------------------------
 class NgeWriter
 {
    public :
-      NgeWriter( void) : m_bBinary( false) {}
+      NgeWriter( void) : m_bBinary( false), m_OutTxtFile( nullptr) {}
       ~NgeWriter( void)
             { Close() ; }
-      bool Init( const std::string& sFileOut, bool bBinary) ;
+      bool Init( const std::string& sFileOut, int nFlag) ;
       bool Close( void) ;
-      void WriteUchar( unsigned char ucVal, const char* szSep, bool bEndL = false) ;
-      void WriteBool( bool bVal, const char* szSep, bool bEndL = false) ;
-      void WriteInt( int nVal, const char* szSep, bool bEndL = false) ;
-      void WriteDouble( double dVal, const char* szSep, bool bEndL = false, int nPrec = 6) ;
-      void WriteVector( const Vector3d& vtV, const char* szSep, bool bEndL = false, int nPrec = 9) ;
-      void WritePoint( const Point3d& ptP, const char* szSep, bool bEndL = false, int nPrec = 6) ;
-      void WritePointW( const Point3d& ptP, double dW, const char* szSep, bool bEndL = false,
+      bool WriteUchar( unsigned char ucVal, const char* szSep, bool bEndL = false) ;
+      bool WriteBool( bool bVal, const char* szSep, bool bEndL = false) ;
+      bool WriteInt( int nVal, const char* szSep, bool bEndL = false) ;
+      bool WriteDouble( double dVal, const char* szSep, bool bEndL = false, int nPrec = 6) ;
+      bool WriteVector( const Vector3d& vtV, const char* szSep, bool bEndL = false, int nPrec = 9) ;
+      bool WritePoint( const Point3d& ptP, const char* szSep, bool bEndL = false, int nPrec = 6) ;
+      bool WritePointW( const Point3d& ptP, double dW, const char* szSep, bool bEndL = false,
                         int nPrecP = 6, int nPrecW = 9) ;
-      void WriteFrame( const Frame3d& frF, const char* szSep, bool bEndL, int nPrecP = 6, int nPrecV = 9) ;
-      void WriteString( const std::string& sVal, const char* szSep, bool bEndL = false) ;
-      void WriteKey( int nKey /* bEndL = true*/) ;
-      void WriteCol( const Color& cCol, const char* szSep, bool bEndL = false) ;
+      bool WriteFrame( const Frame3d& frF, const char* szSep, bool bEndL, int nPrecP = 6, int nPrecV = 9) ;
+      bool WriteString( const std::string& sVal, const char* szSep, bool bEndL = false) ;
+      bool WriteKey( int nKey /* bEndL = true*/) ;
+      bool WriteCol( const Color& cCol, const char* szSep, bool bEndL = false) ;
 
    private :
       bool          m_bBinary ;
-      std::ofstream m_OutFile ;
+      // per file binari
+      std::ofstream m_OutBinFile ;
+      // per file ASCII
+      gzFile_s*     m_OutTxtFile ;
 } ;
diff --git a/SurfTriMesh.cpp b/SurfTriMesh.cpp
index 038672e..d6cf097 100644
--- a/SurfTriMesh.cpp
+++ b/SurfTriMesh.cpp
@@ -404,34 +404,41 @@ bool
 SurfTriMesh::Save( NgeWriter& ngeOut) const
 {
   // tolleranza lineare di costruzione
-   ngeOut.WriteDouble( m_dLinTol, ";") ;
+   if ( ! ngeOut.WriteDouble( m_dLinTol, ";"))
+      return false ;
   // angolo limite per mediare le normali
-   ngeOut.WriteDouble( m_dSmoothAng, ";", true) ;
+   if ( ! ngeOut.WriteDouble( m_dSmoothAng, ";", true))
+      return false ;
   // flag aperta/chiusa
-   ngeOut.WriteBool( m_bClosed, ";") ;
+   if ( ! ngeOut.WriteBool( m_bClosed, ";"))
+      return false ;
   // numero di vertici
-   ngeOut.WriteInt( GetVertexSize(), ";") ;
+   if ( ! ngeOut.WriteInt( GetVertexSize(), ";"))
+      return false ;
   // numero di triangoli
-   ngeOut.WriteInt( GetTriangleSize(), ";", true) ;
+   if ( ! ngeOut.WriteInt( GetTriangleSize(), ";", true))
+      return false ;
   // ciclo sui vertici
    for ( int i = 0 ; i < int( m_vVert.size()) ; ++ i) {
-      ngeOut.WriteInt( i, ";") ;
-      ngeOut.WritePoint( m_vVert[i].ptP, ";") ;
-      ngeOut.WriteInt( m_vVert[i].nIdTria, ";") ;
-      ngeOut.WriteInt( m_vVert[i].nFlag, ";", true) ;
+      if ( ! ngeOut.WriteInt( i, ";")  ||
+           ! ngeOut.WritePoint( m_vVert[i].ptP, ";")  ||
+           ! ngeOut.WriteInt( m_vVert[i].nIdTria, ";")  ||
+           ! ngeOut.WriteInt( m_vVert[i].nFlag, ";", true))
+         return false ;
    }
   // ciclo sui triangoli
    for ( int i = 0 ; i < int( m_vTria.size()) ; ++ i) {
-      ngeOut.WriteInt( i, ";") ;
-      ngeOut.WriteInt( m_vTria[i].nIdVert[0], ",") ;
-      ngeOut.WriteInt( m_vTria[i].nIdVert[1], ",") ;
-      ngeOut.WriteInt( m_vTria[i].nIdVert[2], ";") ;
-      ngeOut.WriteInt( m_vTria[i].nIdAdjac[0], ",") ;
-      ngeOut.WriteInt( m_vTria[i].nIdAdjac[1], ",") ;
-      ngeOut.WriteInt( m_vTria[i].nIdAdjac[2], ";") ;
-      ngeOut.WriteVector( m_vTria[i].vtN, ";") ;
-      ngeOut.WriteInt( m_vTria[i].nTFlag, ";") ;
-      ngeOut.WriteInt( m_vTria[i].nEFlag, ";", true) ;
+      if ( ! ngeOut.WriteInt( i, ";")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdVert[0], ",")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdVert[1], ",")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdVert[2], ";")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdAdjac[0], ",")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdAdjac[1], ",")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nIdAdjac[2], ";")  ||
+           ! ngeOut.WriteVector( m_vTria[i].vtN, ";")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nTFlag, ";")  ||
+           ! ngeOut.WriteInt( m_vTria[i].nEFlag, ";", true))
+         return false ;
    }
 
    return true ;
diff --git a/stdafx.h b/stdafx.h
index 4d461a4..8712f37 100644
--- a/stdafx.h
+++ b/stdafx.h
@@ -28,5 +28,6 @@
 
 #include "/EgtDev/Include/EgtLibVer.h"
 
+#pragma comment(lib, EGTEXTDIR "zlib/lib/zlib" EGTLIBVER ".lib")
 #pragma comment(lib, EGTLIBDIR "EgtGeneral" EGTLIBVER ".lib")
 #pragma comment(lib, EGTLIBDIR "EgtNumKernel" EGTLIBVER ".lib")