The first mapper based on the new index sets

[[Imported from SVN: r2795]]

grid/common/mapper.hh

@@ -6,7 +6,9 @@
 #define __DUNE_MAPPER2_HH__
 
 #include <iostream>
+#include <dune/common/exceptions.hh>
 #include "dune/common/helpertemplates.hh"
+
 /**
  * @file
  * @brief  Mapper classes are used to attach data to a grid
@@ -32,7 +34,106 @@ namespace Dune
    *
    */
 
+  /** @brief A mapper.
+   *
+   * In this implementation of a mapper the entity set used as domain for the map consists
+   * of the entities of a given codimension c for all entities in the given index set. The index
+   * set may only contain entities of a single geometry type, otherwise an exception is thrown. This
+   * version is usually not used directly but is used to implement versions for leafwise and levelwise
+   * entity sets.
+   *
+   * Template parameters are:
+   *
+   * \par G
+   *    A Dune grid type.
+   * \par IS
+   *    LeafIndexSet or LevelIndexSet type of the given grid.
+   * \par c
+   *    A valid codimension.
+   */
+  template <typename G, typename IS, int c>
+  class SingleCodimSingleGeomTypeMapper {
+  public:
+
+    /** @brief Construct mapper from grid and one fo its index sets.
+
+       \param grid A Dune grid object.
+       \param indexset IndexSet object returned by grid.
+
+     */
+    SingleCodimSingleGeomTypeMapper (const G& grid, const IS& indexset);
+
+    /** @brief Map entity to array index.
+
+            \param e Reference to codim cc entity, where cc is the template parameter of the function.
+            \return An index in the range 0 ... Max number of entities in set - 1.
+     */
+    template<int cc>     // this is necessary for multiple codim mappers
+    int map (const typename G::Traits::template Codim<cc>::Entity& e) const;
+
+    /** @brief Map subentity of codim 0 entity to array index.
+
+       \param e Reference to codim 0 entity.
+       \param i Number of codim cc subentity of e, where cc is the template parameter of the function.
+       \return An index in the range 0 ... Max number of entities in set - 1.
+     */
+    template<int cc>     // this is now the subentity's codim
+    int submap (const typename G::Traits::template Codim<0>::Entity& e, int i) const;
+
+    /** @brief Return total number of entities in the entity set managed by the mapper.
+
+       This number can be used to allocate a vector of data elements associated with the
+       entities of the set. In the parallel case this number is per process (i.e. it
+       may be different in different processes).
+
+       \return Size of the entity set.
+     */
+    int size () const;
+
+  private:
+    const G& g;
+    const IS& is;
+  };
+
+
+  template <typename G, typename IS, int c>
+  SingleCodimSingleGeomTypeMapper<G,IS,c>::SingleCodimSingleGeomTypeMapper (const G& grid, const IS& indexset)
+    : g(grid), is(indexset)
+  {
+    // check that grid has only a single geometry type
+    if (is.geomtypes().size() != 1)
+      DUNE_THROW(GridError, "mapper treats only a single codim and a single geometry type");
+  }
+
+  template <typename G, typename IS, int c>
+  template<int cc>
+  int SingleCodimSingleGeomTypeMapper<G,IS,c>::map (const typename G::Traits::template Codim<cc>::Entity& e) const
+  {
+    IsTrue< cc == c >::yes();
+    return is.template index<cc>(e);
+  }
+
+  template <typename G, typename IS, int c>
+  template<int cc>
+  int SingleCodimSingleGeomTypeMapper<G,IS,c>::submap (const typename G::Traits::template Codim<0>::Entity& e, int i) const
+  {
+    IsTrue< cc == c >::yes();
+    return is.template subindex<cc>(e,i);
+  }
+
+  template <typename G, typename IS, int c>
+  int SingleCodimSingleGeomTypeMapper<G,IS,c>::size () const
+  {
+    return is.size(c,is.geomtypes()[0]);
+  }
+
 
+  template <typename G, int c>
+  class LeafSingleCodimSingleGeomTypeMapper : public SingleCodimSingleGeomTypeMapper<G,typename G::LeafIndexSet,c> {
+  public:
+    LeafSingleCodimSingleGeomTypeMapper (const G& grid) : SingleCodimSingleGeomTypeMapper<G,typename G::LeafIndexSet,c>(grid,grid.leafindexset())
+    {}
+  };
 
   /** @} */
 }