Special leaf iterators for UGGrid. Still only for elements, but they should be a lot faster now

[[Imported from SVN: r2474]]

grid/uggrid/uggridleafiterator.hh

+// -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+// vi: set et ts=4 sw=2 sts=2:
+#ifndef DUNE_UGGRIDLEAFITERATOR_HH
+#define DUNE_UGGRIDLEAFITERATOR_HH
+
+#include <dune/grid/uggrid/uggridentitypointer.hh>
+
+/** \file
+ * \brief The UGGridLeafIterator class
+ */
+
+namespace Dune {
+
+#if 0
+  // Forward declaration
+  template <int codim, PartitionIteratorType PiType, class GridImp>
+  class UGGridLevelIteratorFactory;
+#endif
+
+  //**********************************************************************
+  //
+  // --UGGridLevelIterator
+  // --LevelIterator
+  /** \brief Iterator over all entities of a given codimension and level of a grid.
+   * \ingroup UGGrid
+   */
+  template<int codim, PartitionIteratorType pitype, class GridImp>
+  class UGGridLeafIterator :
+    public Dune::UGGridEntityPointer <codim,GridImp>
+  {
+    enum {dim = GridImp::dimension};
+
+    friend class UGGridEntity<codim,dim,GridImp>;
+    friend class UGGridEntity<0,    dim,GridImp>;
+
+    //template <int codim_, PartitionIteratorType PiType_, class GridImp_>
+    //friend class UGGridLevelIteratorFactory;
+
+  public:
+
+    //typedef typename GridImp::template Codim<codim>::Entity Entity;
+    UGGridLeafIterator(const GridImp& grid) : grid_(&grid) {
+
+      const int fullRefineLevel = grid_->multigrid_->fullrefineLevel;
+
+      if (pitype==All_Partition || pitype==Ghost_Partition)
+        setToTarget(UG_NS<dim>::PFirstElement(grid_->multigrid_->grids[fullRefineLevel]), fullRefineLevel);
+      else
+        setToTarget(UG_NS<dim>::FirstElement(grid_->multigrid_->grids[fullRefineLevel]), fullRefineLevel);
+
+    }
+
+    //! Constructor
+    UGGridLeafIterator()
+    {
+      this->virtualEntity_.setToTarget(0);
+    }
+
+    //! prefix increment
+    void increment() {
+      // Increment until you find a leaf entity
+      do {
+        globalIncrement();
+      } while (this->virtualEntity_.getTarget() && !UG_NS<dim>::isLeaf(this->virtualEntity_.getTarget()));
+    }
+
+  private:
+
+    /** \brief This increment makes the iterator wander over all entities on all levels */
+    void globalIncrement() {
+      // Increment on this level
+      this->virtualEntity_.setToTarget(UG_NS<GridImp::dimension>::succ(this->virtualEntity_.getTarget()));
+
+      // If beyond the end of this level set to first of next level
+      if (!this->virtualEntity_.getTarget() && this->level() < grid_->maxlevel()) {
+
+        if (pitype==All_Partition || pitype==Ghost_Partition)
+          setToTarget(UG_NS<dim>::PFirstElement(grid_->multigrid_->grids[this->level()+1]), this->level()+1);
+        else
+          setToTarget(UG_NS<dim>::FirstElement(grid_->multigrid_->grids[this->level()+1]), this->level()+1);
+
+      }
+
+    }
+
+    // /////////////////////////////////////
+    //   Data members
+    // /////////////////////////////////////
+    const GridImp* grid_;
+
+  };
+
+}  // namespace Dune
+
+#endif