Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <cstddef>
       7             : #include <type_traits>
       8             : 
       9             : #include "DataStructures/DataBox/Tag.hpp"
      10             : #include "Utilities/NoSuchType.hpp"
      11             : #include "Utilities/TMPL.hpp"
      12             : #include "Utilities/TypeTraits/CreateGetStaticMemberVariableOrDefault.hpp"
      13             : #include "Utilities/TypeTraits/CreateGetTypeAliasOrDefault.hpp"
      14             : #include "Utilities/TypeTraits/IsA.hpp"
      15             : 
      16             : /// \cond
      17             : namespace Tags {
      18             : template <size_t Dim, typename TagsList>
      19             : struct BoundaryVariables;
      20             : }  // namespace Tags
      21             : /// \endcond
      22             : 
      23             : namespace evolution::dg {
      24           1 : namespace Tags {
      25             : /// \ingroup DiscontinuousGalerkinGroup
      26             : /// \brief The boundary-evolved twin of an interior source field.
      27             : ///
      28             : /// A boundary-evolved field is stored and time-integrated only on external
      29             : /// boundary faces (a pointwise per-face-node ODE); it has no volume extent.
      30             : /// This is a prefix tag wrapping the interior source, so its type matches the
      31             : /// source.
      32             : ///
      33             : /// \note Boundary evolved fields cannot currently be used with AMR or LTS.
      34             : template <typename Source>
      35           1 : struct BoundaryValue : db::PrefixTag, db::SimpleTag {
      36           0 :   using type = typename Source::type;
      37             :   /// The interior source field this boundary field is the twin of.
      38           1 :   using tag = Source;
      39             : };
      40             : }  // namespace Tags
      41             : 
      42             : namespace detail {
      43             : template <typename Tag>
      44             : struct is_boundary_variables_tag : std::false_type {};
      45             : template <size_t Dim, typename TagsList>
      46             : struct is_boundary_variables_tag<::Tags::BoundaryVariables<Dim, TagsList>>
      47             :     : std::true_type {};
      48             : 
      49             : template <typename VariablesTag>
      50             : struct boundary_variables_tag_impl : std::false_type {
      51             :   using type = NoSuchType;
      52             : };
      53             : template <typename VariablesTag>
      54             : requires tt::is_a_v<tmpl::list, VariablesTag>
      55             : struct boundary_variables_tag_impl<VariablesTag> {
      56             :  private:
      57             :   using back = tmpl::back<VariablesTag>;
      58             : 
      59             :  public:
      60             :   static constexpr bool value = is_boundary_variables_tag<back>::value;
      61             :   static_assert(
      62             :       tmpl::count_if<VariablesTag,
      63             :                      tmpl::bind<is_boundary_variables_tag, tmpl::_1>>::value ==
      64             :           (value ? 1 : 0),
      65             :       "A list-valued variables_tag must contain at most one "
      66             :       "::Tags::BoundaryVariables entry, and it must be the last entry.");
      67             :   using type = tmpl::conditional_t<value, back, NoSuchType>;
      68             : };
      69             : }  // namespace detail
      70             : 
      71             : /// \ingroup DiscontinuousGalerkinGroup
      72             : /// \brief Whether the system declares boundary-evolved variables, i.e.
      73             : /// whether `System::variables_tag` is a `tmpl::list` whose last entry is a
      74             : /// `::Tags::BoundaryVariables`.
      75             : template <typename System>
      76           1 : constexpr bool system_has_boundary_variables_v =
      77             :     detail::boundary_variables_tag_impl<typename System::variables_tag>::value;
      78             : 
      79             : /// \ingroup DiscontinuousGalerkinGroup
      80             : /// \brief The `::Tags::BoundaryVariables` entry of the system's list-valued
      81             : /// `variables_tag`, or `NoSuchType` if the system does not declare
      82             : /// boundary-evolved variables.
      83             : template <typename System>
      84           1 : using boundary_variables_tag = typename detail::boundary_variables_tag_impl<
      85             :     typename System::variables_tag>::type;
      86             : 
      87             : /// @{
      88             : /// \ingroup DiscontinuousGalerkinGroup
      89             : /// \brief The projected interior inputs to a boundary condition's
      90             : /// `boundary_field_time_derivatives` method, in the order evolved,
      91             : /// primitive, temporary.
      92             : ///
      93             : /// They are declared separately from the `dg_ghost` interior inputs
      94             : /// (`dg_interior_evolved_variables_tags` etc.) so that a boundary condition
      95             : /// can request a different projected interior state for its boundary-field
      96             : /// time derivative.  The boundary-condition pass projects the requested
      97             : /// fields onto the face exactly as it does for the `dg_ghost` inputs.
      98           1 : CREATE_GET_TYPE_ALIAS_OR_DEFAULT(
      99             :     boundary_field_time_derivatives_evolved_variables_tags)
     100             : CREATE_GET_TYPE_ALIAS_OR_DEFAULT(boundary_field_time_derivatives_primitive_tags)
     101             : CREATE_GET_TYPE_ALIAS_OR_DEFAULT(boundary_field_time_derivatives_temporary_tags)
     102             : 
     103             : template <typename BoundaryCondition>
     104             : using boundary_field_time_derivatives_interior_tags = tmpl::append<
     105             :     get_boundary_field_time_derivatives_evolved_variables_tags_or_default_t<
     106             :         BoundaryCondition, tmpl::list<>>,
     107             :     get_boundary_field_time_derivatives_primitive_tags_or_default_t<
     108             :         BoundaryCondition, tmpl::list<>>,
     109             :     get_boundary_field_time_derivatives_temporary_tags_or_default_t<
     110             :         BoundaryCondition, tmpl::list<>>>;
     111             : /// @}
     112             : 
     113             : namespace detail {
     114             : CREATE_GET_STATIC_MEMBER_VARIABLE_OR_DEFAULT(evolves_boundary_variables)
     115             : 
     116             : // Detect if the boundary condition declares a `boundary_field_time_derivatives`
     117             : // method.
     118             : template <typename BoundaryCondition>
     119             : constexpr bool has_boundary_field_time_derivatives_v = requires {
     120             :   &BoundaryCondition::boundary_field_time_derivatives;
     121             : };
     122             : }  // namespace detail
     123             : 
     124             : /// @{
     125             : /// \ingroup DiscontinuousGalerkinGroup
     126             : /// \brief Whether a boundary condition evolves the system's boundary-evolved
     127             : /// variables: the opt-in is the marker
     128             : /// `static constexpr bool evolves_boundary_variables = true;` on the
     129             : /// boundary condition. An opt-in boundary condition must declare
     130             : /// the method `boundary_field_time_derivatives`.
     131             : template <typename BoundaryCondition>
     132           1 : constexpr bool evolves_boundary_variables_v =
     133             :     detail::get_evolves_boundary_variables_or_default_v<BoundaryCondition,
     134             :                                                         false>;
     135             : /// @}
     136             : }  // namespace evolution::dg