geometry.hh

#ifndef __DUNE_ACFEM_COMMON_GEOMETRY_HH__
#define __DUNE_ACFEM_COMMON_GEOMETRY_HH__
 
#include <cmath>
 
#include <dune/geometry/referenceelements.hh>
 
namespace Dune {
 
  namespace ACFem {
 
    template<class Geometry>
    typename Geometry::ctype h2Estimate(const Geometry& geometry)
    {
      const int dimension = Geometry::mydimension;
      typename Geometry::ctype volume = geometry.volume();
 
      switch(dimension) {
      case 1:
        return volume*volume;
      case 2:
        return volume;
      case 3:
        return std::pow(volume, 2.0/(double)dimension);
      default:
        return -1.0;
      }
    }
 
    template<class Geometry>
    typename Geometry::ctype hEstimate(const Geometry& geometry)
    {
      typedef typename Geometry::ctype ctype;
      const int dimension = Geometry::mydimension;
      const ctype volume = geometry.volume();
 
      switch(dimension) {
      case 1:
        return volume;
      case 2:
        return std::sqrt(volume);
      case 3:
        return std::pow(volume, 1.0/(double)dimension);
      default:
        return -1.0;
      }
    }
 
    template<class GridPart, int codim = 0>
    class GeometryInformation
    {
      using ThisType = GeometryInformation<GridPart, codim>;
    public:
      using GridPartType = GridPart;
 
      static constexpr int dim = GridPartType::dimension - codim;
 
      using ctype = typename GridPartType::ctype;
 
     protected:
      using ReferenceElementsType = Dune::ReferenceElements<ctype, dim>;
 
     public:
      using ReferenceElementType = std::decay_t<decltype(ReferenceElementsType::general(std::declval<const GeometryType&>()))>;
 
      using DomainType = FieldVector<ctype, dim>;
 
    public:
      static const DomainType localCenter(const GeometryType &type)
      {
        return type.isNone() ? DomainType(0) : referenceElement(type).position(0, 0);
      }
 
      static ctype referenceVolume (const GeometryType &type)
      {
        return type.isNone() ? ctype(1.0) : referenceElement(type).volume();
      }
 
      static auto referenceElement(const GeometryType &type)
      {
        assert(!type.isNone());
        return ReferenceElementsType::general( type );
      }
    };
 
  } // namespace ACFem
 
} // namespace Dune
 
#endif // __DUNE_ACFEM_COMMON_GEOMETRY_HH__