{
   new TGeoManager("xtru", "poza12");
   TGeoMaterial *mat = new TGeoMaterial("Al", 26.98,13,2.7);
   TGeoMedium *med = new TGeoMedium("MED",1,mat);
   TGeoVolume *top = gGeoManager->MakeBox("TOP",med,100,100,100);
   gGeoManager->SetTopVolume(top);
   TGeoVolume *vol = gGeoManager->MakeXtru("XTRU",med,4);
   TGeoXtru *xtru = (TGeoXtru*)vol->GetShape();
   Double_t x[8] = {-30,-30,30,30,15,15,-15,-15};
   Double_t y[8] = {-30,30,30,-30,-30,15,15,-30};
   xtru->DefinePolygon(8,x,y);
   xtru->DefineSection(0,-40, -20., 10., 1.5);
   xtru->DefineSection(1, 10, 0., 0., 0.5);
   xtru->DefineSection(2, 10, 0., 0., 0.7);
   xtru->DefineSection(3, 40, 10., 20., 0.9);
   top->AddNode(vol,1);
   gGeoManager->CloseGeometry();
   gGeoManager->SetNsegments(80);
   top->Draw();
   if (gPad) {
      TView *view = gPad->GetView();
      if (view) view->ShowAxis();
    }
}