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git-svn-id: https://svn.dealii.org/trunk@24169 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/include/deal.II/distributed/tria.h b/deal.II/include/deal.II/distributed/tria.h
index 89a319c60cf0ec5083583ab89709a80dd2d42af0..888afd1d6243f581bda94587b9c3a3693436af24 100644 (file)
--- a/deal.II/include/deal.II/distributed/tria.h
+++ b/deal.II/include/deal.II/distributed/tria.h
@@ -208,6 +208,29 @@ namespace parallel
                                          * <code>check_for_distorted_cells</code>
                                          * argument provided by the
                                          * base class.
+                                         *
+                                         * @note While it is possible to pass
+                                         * all of the mesh smoothing flags
+                                         * listed in the base class to
+                                         * objects of this type, it is not
+                                         * always possible to honor all of
+                                         * these smoothing options if they
+                                         * would require knowledge of
+                                         * refinement/coarsening flags on
+                                         * cells not locally owned by this
+                                         * processor. As a consequence, for
+                                         * some of these flags, the ultimate
+                                         * number of cells of the parallel
+                                         * triangulation may depend on the
+                                         * number of processors into which it
+                                         * is partitioned. On the other hand,
+                                         * if no smoothing flags are passed,
+                                         * if you always mark the same cells
+                                         * of the mesh, you will always get
+                                         * the exact same refined mesh
+                                         * independent of the number of
+                                         * processors into which the
+                                         * triangulation is partitioned.
                                          */
        Triangulation (MPI_Comm mpi_communicator,
                       const typename dealii::Triangulation<dim,spacedim>::MeshSmoothing