#include "TSystem.h"
#include "TGeoManager.h"
#include "TGeoMedium.h"


void readgeom(char *fname="rich.gdml")
{
   //--- Definition of a simple geometry
   gSystem->Load("libGeom");
   TGeoManager *geom = new TGeoManager("simple1", "Simple geometry");
   geom->Import(fname);
   TGeoVolume* top=gGeoManager->GetTopVolume();
   top->Print();     
   top->Draw();
   if (gPad) gPad->x3d();
}