Improve code documentation for global numbering.

src/libparmmg.c

@@ -1085,13 +1085,17 @@ int PMMG_Compute_verticesGloNum( PMMG_pParMesh parmesh,MPI_Comm comm ){
 
  /* Mark nodes with the owner color (overwritten by higher-rank procs) */
  for( iproc = 0; iproc < parmesh->nprocs; iproc++ ) {
+ /* Travel the communicators in increasing order of neighbour rank */
  icomm = iproc2comm[iproc];
  if( icomm == PMMG_UNSET ) continue;
  ext_node_comm = &parmesh->ext_node_comm[icomm];
  color = MG_MAX(parmesh->myrank,ext_node_comm->color_out);
  /* Mark nodes */
  for( i = 0; i < ext_node_comm->nitem; i++ ) {
  idx = ext_node_comm->int_comm_index[i];
+ /* This affectation is right because we ensured that we travel the
+ * communicators in increasing order. Note that intvalues is not
+ * initialized before this stage so it containes fake values. */
  intvalues[idx] = color;
  }
  }