qprojector.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2005 - 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.md at
// the top level directory of deal.II.
//
// ---------------------------------------------------------------------

#ifndef dealii_qprojector_h
#define dealii_qprojector_h


#include <deal.II/base/geometry_info.h>
#include <deal.II/base/quadrature.h>

DEAL_II_NAMESPACE_OPEN




template <int dim>
class QProjector
{
public:
  using SubQuadrature = Quadrature<dim - 1>;

  static void
  project_to_face(const SubQuadrature &    quadrature,
                  const unsigned int       face_no,
                  std::vector<Point<dim>> &q_points);

  static Quadrature<dim>
  project_to_face(const SubQuadrature &quadrature, const unsigned int face_no);

  static void
  project_to_subface(const SubQuadrature &          quadrature,
                     const unsigned int             face_no,
                     const unsigned int             subface_no,
                     std::vector<Point<dim>> &      q_points,
                     const RefinementCase<dim - 1> &ref_case =
                       RefinementCase<dim - 1>::isotropic_refinement);

  static Quadrature<dim>
  project_to_subface(const SubQuadrature &          quadrature,
                     const unsigned int             face_no,
                     const unsigned int             subface_no,
                     const RefinementCase<dim - 1> &ref_case =
                       RefinementCase<dim - 1>::isotropic_refinement);

  static Quadrature<dim>
  project_to_all_faces(const SubQuadrature &quadrature);

  static Quadrature<dim>
  project_to_all_subfaces(const SubQuadrature &quadrature);

  static Quadrature<dim>
  project_to_child(const Quadrature<dim> &quadrature,
                   const unsigned int     child_no);

  static Quadrature<dim>
  project_to_all_children(const Quadrature<dim> &quadrature);

  static Quadrature<dim>
  project_to_line(const Quadrature<1> &quadrature,
                  const Point<dim> &   p1,
                  const Point<dim> &   p2);

  class DataSetDescriptor
  {
  public:
    DataSetDescriptor();

    static DataSetDescriptor
    cell();

    static DataSetDescriptor
    face(const unsigned int face_no,
         const bool         face_orientation,
         const bool         face_flip,
         const bool         face_rotation,
         const unsigned int n_quadrature_points);

    static DataSetDescriptor
    subface(const unsigned int               face_no,
            const unsigned int               subface_no,
            const bool                       face_orientation,
            const bool                       face_flip,
            const bool                       face_rotation,
            const unsigned int               n_quadrature_points,
            const internal::SubfaceCase<dim> ref_case =
              internal::SubfaceCase<dim>::case_isotropic);

    operator unsigned int() const;

  private:
    const unsigned int dataset_offset;

    DataSetDescriptor(const unsigned int dataset_offset);
  };

private:
  static Quadrature<2>
  reflect(const Quadrature<2> &q);

  static Quadrature<2>
  rotate(const Quadrature<2> &q, const unsigned int n_times);
};

// -------------------  inline and template functions ----------------



template <int dim>
inline QProjector<dim>::DataSetDescriptor::DataSetDescriptor(
  const unsigned int dataset_offset)
  : dataset_offset(dataset_offset)
{}


template <int dim>
inline QProjector<dim>::DataSetDescriptor::DataSetDescriptor()
  : dataset_offset(numbers::invalid_unsigned_int)
{}



template <int dim>
typename QProjector<dim>::DataSetDescriptor
QProjector<dim>::DataSetDescriptor::cell()
{
  return 0;
}



template <int dim>
inline QProjector<dim>::DataSetDescriptor::operator unsigned int() const
{
  return dataset_offset;
}


/* -------------- declaration of explicit specializations ------------- */

#ifndef DOXYGEN


template <>
void
QProjector<1>::project_to_face(const Quadrature<0> &,
                               const unsigned int,
                               std::vector<Point<1>> &);
template <>
void
QProjector<2>::project_to_face(const Quadrature<1> &  quadrature,
                               const unsigned int     face_no,
                               std::vector<Point<2>> &q_points);
template <>
void
QProjector<3>::project_to_face(const Quadrature<2> &  quadrature,
                               const unsigned int     face_no,
                               std::vector<Point<3>> &q_points);

template <>
Quadrature<1>
QProjector<1>::project_to_all_faces(const Quadrature<0> &quadrature);


template <>
void
QProjector<1>::project_to_subface(const Quadrature<0> &,
                                  const unsigned int,
                                  const unsigned int,
                                  std::vector<Point<1>> &,
                                  const RefinementCase<0> &);
template <>
void
QProjector<2>::project_to_subface(const Quadrature<1> &  quadrature,
                                  const unsigned int     face_no,
                                  const unsigned int     subface_no,
                                  std::vector<Point<2>> &q_points,
                                  const RefinementCase<1> &);
template <>
void
QProjector<3>::project_to_subface(const Quadrature<2> &    quadrature,
                                  const unsigned int       face_no,
                                  const unsigned int       subface_no,
                                  std::vector<Point<3>> &  q_points,
                                  const RefinementCase<2> &face_ref_case);

template <>
Quadrature<1>
QProjector<1>::project_to_all_subfaces(const Quadrature<0> &quadrature);

template <>
QIterated<1>::QIterated(const Quadrature<1> &base_quadrature,
                        const unsigned int   n_copies);


#endif // DOXYGEN
DEAL_II_NAMESPACE_CLOSE

#endif