allow to recluster for local kfac

enabled by METS_BBAR_MODE 4, defaults to off

SHERPA/PerturbativePhysics/Perturbative_Interface.C

@@ -201,9 +201,17 @@ DefineInitialConditions(ATOOLS::Blob *blob)
   if (p_me->Process()->Info().m_ckkw&1) {
     if ((m_bbarmode&1) && p_me->HasNLO() &&
         p_me->Process()->Parent()->Info().m_fi.NLOType()==nlo_type::lo) {
-        if (!LocalKFactor(p_ampl)) {
-          DEBUG_INFO("didn't find PowProc in exclusively clustered amplitude");
+      if (!LocalKFactor(p_ampl)) {
+	DEBUG_INFO("didn't find process using original amplitude");
+	if (m_bbarmode&4) {
+	  Cluster_Amplitude *ampl=p_me->Process()->
+	    Get<Single_Process>()->Cluster(m_cmode|256|512);
+	  while (ampl->Prev()) ampl=ampl->Prev();
+	  if (!LocalKFactor(ampl))
+	    DEBUG_INFO("didn't find process using exclusive clustering");
+	  ampl->Delete();
 	}
+      }
     }
     blob->AddData("Sud_Weight",new Blob_Data<double>(m_weight));
     if (p_me->EventGenerationMode()!=0) {