diff --git a/SurfFlatRegion.cpp b/SurfFlatRegion.cpp
index cbf02af..6b7ddf1 100644
--- a/SurfFlatRegion.cpp
+++ b/SurfFlatRegion.cpp
@@ -968,6 +968,22 @@ SurfFlatRegion::GetLoop( int nChunk, int nLoop) const
    return pCrv ;
 }
 
+//----------------------------------------------------------------------------
+bool
+SurfFlatRegion::ApproxLoopWithLines( int nChunk, int nLoop, double dLinTol, double dAngTolDeg, int nType, PolyLine& PL) const
+{
+  // recupero il loop nel riferimento intrinseco
+   const ICurve* pMyCrv = GetMyLoop( nChunk, nLoop) ;
+   if ( pMyCrv == nullptr)
+      return false ;
+  // ne creo una approssimazione
+   if ( ! pMyCrv->ApproxWithLines( dLinTol, dAngTolDeg, nType, PL))
+      return false ;
+  // la porto nel riferimento in cui č inserito l'oggetto
+   PL.ToGlob( m_frF) ;
+   return true ;
+}
+
 //----------------------------------------------------------------------------
 const ISurfTriMesh*
 SurfFlatRegion::GetAuxSurf( void) const
diff --git a/SurfFlatRegion.h b/SurfFlatRegion.h
index 5947257..892ab75 100644
--- a/SurfFlatRegion.h
+++ b/SurfFlatRegion.h
@@ -84,6 +84,7 @@ class SurfFlatRegion : public ISurfFlatRegion, public IGeoObjRW
       int  GetChunkCount( void) const override ;
       int  GetLoopCount( int nChunk) const override ;
       ICurve* GetLoop( int nChunk, int nLoop) const override ;   // nChunk 0-based, nLoop 0-based (1°esterno, successivi interni) 
+      bool ApproxLoopWithLines( int nChunk, int nLoop, double dLinTol, double dAngTolDeg, int nType, PolyLine& PL) const override ;
       const ISurfTriMesh* GetAuxSurf( void) const override ;
       SurfFlatRegion* CloneChunk( int nChunk) const override ;
       bool GetChunkCentroid( int nChunk, Point3d& ptCen) const override ;