Remove an outdated comment.

Replace it with links to places where the comments are up to date.

diff --git a/include/deal.II/fe/fe_update_flags.h b/include/deal.II/fe/fe_update_flags.h
index cd322cbfa041e3d2ed25c87e07137506ec43f22a..05f3224452102a76ec90a8cafde8cf8c531d505f 100644 (file)
--- a/include/deal.II/fe/fe_update_flags.h
+++ b/include/deal.II/fe/fe_update_flags.h
@@ -51,40 +51,12 @@ template <int,int> class FiniteElement;
  * You can select more than one flag by concatenation using the bitwise or
  * operator|(UpdateFlags,UpdateFlags).
  *
- * <h3>Generating the actual flags</h3>
+ * <h3>Use of these flags flags</h3>
  *
- * When given a set of UpdateFlags @p flags, the FEValues object must
- * determine, which values will have to be computed once only for the
- * reference cell and which values will have to be updated for each cell.
- * Here, it is important to note that in many cases, the FiniteElement will
- * require additional updates from the Mapping. To this end, several auxiliary
- * functions have been implemented:
- *
- * FiniteElement::update_once(flags) and FiniteElement::update_each(flags)
- * determine the values required by the FiniteElement once or on each cell.
- * The same functions exist in Mapping.
- *
- * Since the FiniteElement does not know if a value required from Mapping
- * should be computed once or for each cell,
- * FEValuesBase::compute_update_flags() is used to compute the union of all
- * values to be computed ever. It does this by first adding to the flags set
- * by the user all flags (once and each) added by the FiniteElement. This new
- * set of flags is then given to the Mapping and all flags required there are
- * added, again once and each.
- *
- * This union of all flags is given to Mapping::fill_fe_values() and
- * FiniteElement::fill_fe_values, where it is split again into the information
- * generated only once and the information that must be updated on each cell.
- *
- * The flags finally stored in FEValues then are the union of all the flags
- * required by the user, by FiniteElement and by Mapping, for computation once
- * or on each cell. Subsequent calls to the functions @p update_once and @p
- * update_each should just select among these flags, but should not add new
- * flags.
- *
- * The mechanism by which all this is accomplished is also discussed on the
- * page on
- * @ref UpdateFlags.
+ * More information on the use of this type both in user code as
+ * well as internally can be found in the documentation modules on
+ * @ref UpdateFlags "The interplay of UpdateFlags, Mapping, and FiniteElement in FEValues"
+ * and @ref FE_vs_Mapping_vs_FEValues "How Mapping, FiniteElement, and FEValues work together".
  */
 enum UpdateFlags
 {