diff --git a/ObjEGrGraphics.h b/ObjEGrGraphics.h
index 1333c65..d0db8da 100644
--- a/ObjEGrGraphics.h
+++ b/ObjEGrGraphics.h
@@ -31,6 +31,9 @@ class ObjEGrGraphics : public IObjGraphics
       virtual bool AddColor( const Color& colC) = 0 ;
       virtual bool AddPoint( const Point3d& ptP) = 0 ;
       virtual bool AddPolyLine( const PolyLine& PL) = 0 ;
+      virtual bool StartTriangles( void) = 0 ;
+      virtual bool AddTriangle( const Point3d& ptP0, const Point3d& ptP1, const Point3d& ptP2) = 0 ;
+      virtual bool EndTriangles( void) = 0 ;
       virtual bool Draw( int nStat, int nMark) = 0 ;
 } ;
 
diff --git a/ObjNewGraphics.h b/ObjNewGraphics.h
index caa96dd..67fb092 100644
--- a/ObjNewGraphics.h
+++ b/ObjNewGraphics.h
@@ -69,6 +69,12 @@ class ObjNewGraphics : public ObjEGrGraphics
       virtual bool AddColor( const Color& colC) ;
       virtual bool AddPoint( const Point3d& ptP) ;
       virtual bool AddPolyLine( const PolyLine& PL) ;
+      virtual bool StartTriangles( void)
+                      { return false ; }
+      virtual bool AddTriangle( const Point3d& ptP0, const Point3d& ptP1, const Point3d& ptP2)
+                      { return false ; }
+      virtual bool EndTriangles( void)
+                      { return false ; }
       virtual bool Draw( int nStat, int nMark) ;
 
    public :
diff --git a/ObjOldGraphics.cpp b/ObjOldGraphics.cpp
index 788dd55..cdd5be8 100644
--- a/ObjOldGraphics.cpp
+++ b/ObjOldGraphics.cpp
@@ -51,6 +51,9 @@ ObjOldGraphics::AddColor( const Color& colC)
 bool
 ObjOldGraphics::AddPoint( const Point3d& ptP)
 {
+  // modo corrente deve essere nullo
+   if ( m_nCurrMode != GL_NONE)
+      return false ;
   // start
    AddStart( GL_POINTS) ;
   // inserisco il nuovo vertice
@@ -67,6 +70,9 @@ ObjOldGraphics::AddPoint( const Point3d& ptP)
 bool
 ObjOldGraphics::AddPolyLine( const PolyLine& PL)
 {
+  // modo corrente deve essere nullo
+   if ( m_nCurrMode != GL_NONE)
+      return false ;
   // start
    AddStart( GL_LINE_STRIP) ;
   // inserisco i nuovi vertici
@@ -81,6 +87,49 @@ ObjOldGraphics::AddPolyLine( const PolyLine& PL)
    return true ;
 }
 
+//----------------------------------------------------------------------------
+bool
+ObjOldGraphics::StartTriangles( void)
+{
+  // modo corrente deve essere nullo
+   if ( m_nCurrMode != GL_NONE)
+      return false ;
+  // inizio emissione triangoli
+   AddStart( GL_TRIANGLES) ;
+   m_nCurrMode = GL_TRIANGLES ;
+   return true ;
+}
+
+//----------------------------------------------------------------------------
+bool
+ObjOldGraphics::AddTriangle( const Point3d& ptP0, const Point3d& ptP1, const Point3d& ptP2)
+{
+  // modo corrente deve essere triangoli
+   if ( m_nCurrMode != GL_TRIANGLES)
+      return false ;
+  // emetto i vertici del triangolo
+   AddVert3f( ptP0.x, ptP0.y, ptP0.z) ;
+   AddVert3f( ptP1.x, ptP1.y, ptP1.z) ;
+   AddVert3f( ptP2.x, ptP2.y, ptP2.z) ;
+   return true ;
+}
+
+//----------------------------------------------------------------------------
+bool
+ObjOldGraphics::EndTriangles( void)
+{
+  // modo corrente deve essere triangoli
+   if ( m_nCurrMode != GL_TRIANGLES)
+      return false ;
+  // termino il modo triangoli
+   AddEnd() ;
+   m_nCurrMode = GL_NONE ;
+  // dichiaro valida la grafica
+   m_bValid = true ;
+
+   return true ;
+}
+
 //----------------------------------------------------------------------------
 bool
 ObjOldGraphics::Draw( int nStat, int nMark)
diff --git a/ObjOldGraphics.h b/ObjOldGraphics.h
index 7bfc374..4cf01ed 100644
--- a/ObjOldGraphics.h
+++ b/ObjOldGraphics.h
@@ -14,6 +14,7 @@
 #pragma once
 
 #include "ObjEGrGraphics.h"
+#include "OpenGL.h"
 #include <list>
 
 class Color ;
@@ -70,10 +71,13 @@ class ObjOldGraphics : public ObjEGrGraphics
       virtual bool AddColor( const Color& colC) ;
       virtual bool AddPoint( const Point3d& ptP) ;
       virtual bool AddPolyLine( const PolyLine& PL) ;
+      virtual bool StartTriangles( void) ;
+      virtual bool AddTriangle( const Point3d& ptP0, const Point3d& ptP1, const Point3d& ptP2) ;
+      virtual bool EndTriangles( void) ;
       virtual bool Draw( int nStat, int nMark) ;
 
    public :
-      ObjOldGraphics( void) : m_pScene( nullptr), m_bValid( false) {}
+      ObjOldGraphics( void) : m_pScene( nullptr), m_nCurrMode( GL_NONE), m_bValid( false) {}
 
    private :
       bool AddOldGrAtom( const OldGrAtom& oga)
@@ -103,6 +107,7 @@ class ObjOldGraphics : public ObjEGrGraphics
    private :
       Scene* m_pScene ;            // puntatore alla scena
       bool m_bValid ;              // flag
+      int  m_nCurrMode ;           // modo corrente
       OGALIST m_ogaList ;          // lista di atomi per vecchia grafica
 } ;
 
diff --git a/SceneBasic.cpp b/SceneBasic.cpp
index 1a61788..5257ad5 100644
--- a/SceneBasic.cpp
+++ b/SceneBasic.cpp
@@ -512,6 +512,9 @@ Scene::Background( void)
   // disabilito lo Zdepth
    glDisable( GL_DEPTH_TEST) ;
 
+  // imposto riempimento poligoni
+   glPolygonMode( GL_FRONT_AND_BACK, GL_FILL) ;
+
   // disegno lo sfondo con due colori
    if ( ! m_bNewWay) {
       glBegin( GL_TRIANGLE_STRIP) ;
@@ -629,6 +632,9 @@ Scene::Draw( void)
   // imposto la dimensione standard dei punti
    glPointSize( 3) ;
 
+  // imposto disegno wireframe anche per poligoni
+   glPolygonMode( GL_FRONT_AND_BACK, GL_LINE) ;
+
   // disegno le geometrie del DB
    DrawGroup( GDB_ID_ROOT, GDB_MD_STD, GDB_ST_ON, GDB_MK_OFF) ;
 
diff --git a/SceneGeom.cpp b/SceneGeom.cpp
index 4c90160..29cccc2 100644
--- a/SceneGeom.cpp
+++ b/SceneGeom.cpp
@@ -24,6 +24,7 @@
 #include "/EgtDev/Include/EGkGeoVector3d.h"
 #include "/EgtDev/Include/EGkGeoPoint3d.h"
 #include "/EgtDev/Include/EGkCurve.h"
+#include "/EgtDev/Include/EGkSurfTriMesh.h"
 #include "/EgtDev/Include/EGkGdbFunct.h"
 
 using namespace std ;
@@ -250,6 +251,25 @@ Scene::DrawGeoObj( const IGdbIterator& iIter, int nObjStat, int nObjMark)
          pGraphics->AddColor( cCol) ;
          pGraphics->AddPolyLine( PL) ; 
       }
+     // se superficie trimesh
+      else if ( nGeoType == SRF_TRIMESH) {
+        // recupero la superficie
+         const ISurfTriMesh* pSTM = GetSurfTriMesh( pGeoObj) ;
+         if ( pSTM == nullptr)
+            return false ;
+        // impostazioni iniziali
+         pGraphics->Clear() ;
+         pGraphics->AddColor( cCol) ;
+         pGraphics->StartTriangles() ;
+        // ciclo sui triangoli della superficie
+         Point3d ptP0, ptP1, ptP2 ;
+         int nId = pSTM->GetFirstTriangle( ptP0, ptP1, ptP2) ;
+         while ( nId != -1) {
+            pGraphics->AddTriangle( ptP0, ptP1, ptP2) ;
+            nId = pSTM->GetNextTriangle( nId, ptP0, ptP1, ptP2) ;
+         }
+         pGraphics->EndTriangles() ;
+      }
    }
 
   // visualizzo la grafica associata