void Macro(void)
{

  TGeoManager::Import("Mygeometry.gdml");
  gGeoManager->GetTopVolume()->Draw("ogl");

  TPolyLine3D* gtracksXYZ = new TPolyLine3D(8,"");
  gtracksXYZ->SetLineColor(kBlue);
  gtracksXYZ->SetLineWidth(2);
  gtracksXYZ->SetLineStyle(2);

  gtracksXYZ->SetPoint(0,0.0,0.0,-10.0);
  gtracksXYZ->SetPoint(1,0.0,0.0,  0.0);
  gtracksXYZ->SetPoint(2,0.0,0.0,  1.5);
  gtracksXYZ->SetPoint(3,0.0,0.0,  4.5);
  gtracksXYZ->SetPoint(4,0.0,0.0,  6.0);
  gtracksXYZ->SetPoint(5,0.0,0.0,  9.0);
  gtracksXYZ->SetPoint(6,0.0,0.0, 10.5);
  gtracksXYZ->SetPoint(7,0.0,0.0, 11.0);

  gtracksXYZ->Draw();

}