bounding_box.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2017 - 2019 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_base_bounding_box_h
#define dealii_base_bounding_box_h


#include <deal.II/base/config.h>

#include <deal.II/base/exceptions.h>
#include <deal.II/base/point.h>
#include <deal.II/base/utilities.h>

DEAL_II_NAMESPACE_OPEN

enum class NeighborType
{
  not_neighbors = 0,

  simple_neighbors = 1,

  attached_neighbors = 2,

  mergeable_neighbors = 3
};

template <int spacedim, typename Number = double>
class BoundingBox
{
public:
  BoundingBox() = default;

  BoundingBox(const std::pair<Point<spacedim, Number>, Point<spacedim, Number>>
                &boundary_points);

  template <class Container>
  BoundingBox(const Container &points);

  std::pair<Point<spacedim, Number>, Point<spacedim, Number>> &
  get_boundary_points();

  const std::pair<Point<spacedim, Number>, Point<spacedim, Number>> &
  get_boundary_points() const;

  NeighborType
  get_neighbor_type(const BoundingBox<spacedim, Number> &other_bbox) const;

  void
  merge_with(const BoundingBox<spacedim, Number> &other_bbox);

  bool
  point_inside(const Point<spacedim, Number> &p) const;

  void
  extend(const Number &amount);

  double
  volume() const;

  template <class Archive>
  void
  serialize(Archive &ar, const unsigned int version);

private:
  std::pair<Point<spacedim, Number>, Point<spacedim, Number>> boundary_points;
};

/*------------------------ Inline functions: BoundingBox --------------------*/

#ifndef DOXYGEN


template <int spacedim, typename Number>
inline BoundingBox<spacedim, Number>::BoundingBox(
  const std::pair<Point<spacedim, Number>, Point<spacedim, Number>>
    &boundary_points)
{
  // We check the Bounding Box is not degenerate
  for (unsigned int i = 0; i < spacedim; ++i)
    Assert(boundary_points.first[i] <= boundary_points.second[i],
           ExcMessage("Bounding Box can't be created: the points' "
                      "order should be bottom left, top right!"));

  this->boundary_points = boundary_points;
}



template <int spacedim, typename Number>
template <class Container>
inline BoundingBox<spacedim, Number>::BoundingBox(const Container &points)
{
  boost::geometry::envelope(
    boost::geometry::model::multi_point<Point<spacedim, Number>>(points.begin(),
                                                                 points.end()),
    *this);
}



template <int spacedim, typename Number>
inline void
BoundingBox<spacedim, Number>::extend(const Number &amount)
{
  for (unsigned int d = 0; d < spacedim; ++d)
    {
      boundary_points.first[d] -= amount;
      boundary_points.second[d] += amount;
      Assert(boundary_points.first[d] <= boundary_points.second[d],
             ExcMessage("Bounding Box can't be shrunk this much: the points' "
                        "order should remain bottom left, top right."));
    }
}


template <int spacedim, typename Number>
template <class Archive>
void
BoundingBox<spacedim, Number>::serialize(Archive &ar,
                                         const unsigned int /*version*/)
{
  ar &boundary_points;
}

#endif // DOXYGEN
DEAL_II_NAMESPACE_CLOSE

#endif