fe_field_function.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2007 - 2018 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE at
// the top level of the deal.II distribution.
//
// ---------------------------------------------------------------------

#ifndef dealii_fe_function_h
#define dealii_fe_function_h

#include <deal.II/base/function.h>
#include <deal.II/dofs/dof_handler.h>
#include <deal.II/dofs/dof_accessor.h>
#include <deal.II/fe/mapping_q1.h>
#include <deal.II/base/function.h>
#include <deal.II/base/point.h>
#include <deal.II/base/tensor.h>
#include <deal.II/base/thread_local_storage.h>
#include <deal.II/grid/grid_tools_cache.h>

#include <deal.II/lac/vector.h>

#include <boost/optional.hpp>


DEAL_II_NAMESPACE_OPEN

namespace VectorTools
{
  class ExcPointNotAvailableHere;
}

namespace Functions
{

  template <int dim,
            typename DoFHandlerType=DoFHandler<dim>,
            typename VectorType=Vector<double> >
  class FEFieldFunction :  public Function<dim, typename VectorType::value_type>
  {
  public:
    FEFieldFunction (const DoFHandlerType &dh,
                     const VectorType     &data_vector,
                     const Mapping<dim>   &mapping = StaticMappingQ1<dim>::mapping);

    void set_active_cell (const typename DoFHandlerType::active_cell_iterator &newcell);

    virtual void vector_value (const Point<dim> &p,
                               Vector<typename VectorType::value_type>   &values) const;

    virtual typename VectorType::value_type value (const Point< dim > &p,
                                                   const unsigned int  component = 0)    const;

    virtual void value_list (const std::vector<Point< dim > >     &points,
                             std::vector<typename VectorType::value_type > &values,
                             const unsigned int  component = 0)    const;


    virtual void vector_value_list (const std::vector<Point< dim > >     &points,
                                    std::vector<Vector<typename VectorType::value_type> > &values) const;

    virtual void
    vector_gradient (const Point< dim > &p,
                     std::vector< Tensor< 1, dim,typename VectorType::value_type > > &gradients) const;

    virtual Tensor<1,dim,typename VectorType::value_type> gradient(const Point< dim > &p,
        const unsigned int component = 0)const;

    virtual void
    vector_gradient_list (const std::vector< Point< dim > > &p,
                          std::vector<
                          std::vector< Tensor< 1, dim,typename VectorType::value_type > > > &gradients) const;

    virtual void
    gradient_list (const std::vector< Point< dim > > &p,
                   std::vector< Tensor< 1, dim,typename VectorType::value_type > > &gradients,
                   const unsigned int component=0) const;


    virtual typename VectorType::value_type
    laplacian (const Point<dim>   &p,
               const unsigned int  component = 0) const;

    virtual void
    vector_laplacian (const Point<dim>   &p,
                      Vector<typename VectorType::value_type>     &values) const;

    virtual void
    laplacian_list (const std::vector<Point<dim> > &points,
                    std::vector<typename VectorType::value_type>            &values,
                    const unsigned int              component = 0) const;

    virtual void
    vector_laplacian_list (const std::vector<Point<dim> > &points,
                           std::vector<Vector<typename VectorType::value_type> >   &values) const;

    unsigned int
    compute_point_locations
    (const std::vector<Point<dim> >                              &points,
     std::vector<typename DoFHandlerType::active_cell_iterator > &cells,
     std::vector<std::vector<Point<dim> > >                      &qpoints,
     std::vector<std::vector<unsigned int> >                     &maps) const;

  private:
    typedef
    Threads::ThreadLocalStorage <typename DoFHandlerType::active_cell_iterator >
    cell_hint_t;

    SmartPointer<const DoFHandlerType,FEFieldFunction<dim, DoFHandlerType, VectorType> > dh;

    const VectorType &data_vector;

    const Mapping<dim> &mapping;

    GridTools::Cache<dim,DoFHandlerType::space_dimension> cache;

    mutable cell_hint_t cell_hint;

    boost::optional<Point<dim> >
    get_reference_coordinates (const typename DoFHandlerType::active_cell_iterator &cell,
                               const Point<dim>                                    &point) const;
  };
}

DEAL_II_NAMESPACE_CLOSE

#endif