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#include "../descriptor.h"
#include <forstio/codec/data.hpp>
#include <iostream>
namespace kel {
namespace lbm {
namespace sch {
using namespace saw::schema;
/**
* Basic distribution function
* Base type
* D
* Q
* Scalar factor
* D factor
* Q factor
*/
using T = Float32;
using D2Q5 = Descriptor<2,5>;
template<typename Desc>
using DfCell = Cell<T, Desc, 0, 0, 1>;
template<typename Desc>
using CellInfo = Cell<UInt8, D2Q5, 1, 0, 0>;
/**
* Basic type for simulation
*/
template<typename Desc>
using CellStruct = Struct<
Member<DfCell<Desc>, "dfs">,
Member<CellInfo<Desc>, "info">
>;
using CavityFieldD2Q5 = Field<D2Q5, CellStruct<D2Q5>>;
}
/*
template<typename T, typename Encode>
class df_cell_view;
*/
/**
* Minor helper for the AA-Pull Pattern
*/
/*
template<typename Desc, size_t SN, size_t DN, size_t QN, typename Encode>
class df_cell_view<sch::Cell<sch::T, Desc, SN, DN, QN>, Encode> {
public:
using Schema = sch::Cell<sch::T,Desc,SN,DN,QN>;
private:
std::array<std::decay_t<typename saw::native_data_type<sch::T>::type>*, QN> view_;
public:
df_cell_view(const std::array<std::decay_t<typename saw::native_data_type<sch::T>::type>*, QN>& view):
view_{view}
{}
};
*/
template<typename Desc>
class collision {
public:
typename saw::native_data_type<sch::T>::type relaxation_;
public:
std::array<typename saw::native_data_type<sch::T>::type,Desc::Q> equilibrium(
typename saw::native_data_type<sch::T>::type rho,
std::array<typename saw::native_data_type<sch::T>::type, Desc::D> vel
){
using dfi = df_info<sch::T, Desc>;
typename std::array<saw::native_data_type<sch::T>::type,Desc::Q> eq;
for(std::size_t i = 0; i < eq.size(); ++i){
auto vel_c = (vel[0]*dfi::directions[i][0] + vel[1]*dfi::directions[i][1]);
auto vel_c_cs2 = vel_c / dfi::cs2;
eq[i] = dfi::weights[i] * rho * (
1
+ vel_c_cs2
+ vel_c_cs2 * vel_c_cs2
- ( vel[0] * vel[0] + vel[1] * vel[1] ) / ( 2. * dfi::cs2 )
);
}
return eq;
}
void compute_rho_u(
saw::data<sch::DfCell<sch::D2Q5>>& dfs,
typename saw::native_data_type<sch::T>::type& rho,
std::array<typename saw::native_data_type<sch::T>::type, 2>& vel
){
using dfi = df_info<sch::T, Desc>;
rho = 0;
std::fill(vel.begin(), vel.end(), 0);
for(size_t i = 0; i < Desc::Q; ++i){
rho += dfs(i).get();
vel[0] += dfi::directions[i][0] * dfs(i).get();
vel[1] += dfi::directions[i][1] * dfs(i).get();
}
vel[0] /= rho;
vel[1] /= rho;
}
};
}
}
constexpr size_t dim_size = 2;
constexpr size_t dim_x = 32;
constexpr size_t dim_y = 32;
struct rectangle {
std::array<size_t,4> data_;
rectangle(size_t x, size_t y, size_t w, size_t h):
data_{x,y,w,h}
{}
bool inside(size_t i, size_t j) const {
return !(i < data_[0] || i > (data_[0]+data_[2]) || j < data_[1] || j > (data_[1] +data_[3]));
}
};
template<typename Func>
void apply_for_cells(Func&& func, saw::data<kel::lbm::sch::CavityFieldD2Q5>& dat){
for(std::size_t i = 0; i < dat.template get_dim_size<0>().get(); ++i){
for(std::size_t j = 0; j < dat.template get_dim_size<1>().get(); ++j){
func(dat({i,j}), i, j);
}
}
}
void set_geometry(saw::data<kel::lbm::sch::CavityFieldD2Q5>& latt){
using namespace kel::lbm;
apply_for_cells([](auto& cell, std::size_t i, std::size_t j){
uint8_t val = 0;
if(i == 1){
val = 2;
}
if(j == 1 || (i+2) == dim_x || (j+2) == dim_y){
val = 3;
}
if(i == 0 || j == 0 || (i+1) == dim_x || (j+1) == dim_y){
val = 1;
}
cell.template get<"info">()(0).set(val);
}, latt);
}
void set_initial_conditions(saw::data<kel::lbm::sch::CavityFieldD2Q5>& latt){
using namespace kel::lbm;
apply_for_cells([](auto& cell, std::size_t i, std::size_t j){
(void) i;
(void) j;
auto& dfs = cell.template get<"dfs">();
dfs(0).set(1.0);
}, latt);
}
void lbm_step(
saw::data<kel::lbm::sch::CavityFieldD2Q5>& old_latt,
saw::data<kel::lbm::sch::CavityFieldD2Q5>& new_latt
){
}
int main(){
using namespace kel::lbm;
saw::data<
sch::FixedArray<
sch::CavityFieldD2Q5, 2
>
, saw::encode::Native
> lattices; //{dim_x, dim_y};
auto& df_field = lattices.at(0).template get<"dfs">();
//for(uint64_t i = 0; i < df_field.get_dim_size<0u>(); ++i){
// lattices.at(i) = {dim_x, dim_y};
//}
/**
* Set meta information describing what this cell is
*/
set_geometry(lattices.at(0));
/**
*
*/
set_initial_conditions(lattices.at(0));
/**
* Timeloop
*/
/**
* Print basic setup info
*/
apply_for_cells([](auto& cell, std::size_t i, std::size_t j){
// Not needed
(void) i;
std::cout<<static_cast<uint32_t>(cell.template get<"info">().at(0).get());
if( (j+1) < dim_y){
std::cout<<" ";
}else{
std::cout<<"\n";
}
}, lattices.at(0));
std::cout<<"\n";
apply_for_cells([](auto& cell, std::size_t i, std::size_t j){
// Not needed
(void) i;
std::cout<<cell.template get<"dfs">().at(0).get();
if( (j+1) < dim_y){
std::cout<<" ";
}else{
std::cout<<"\n";
}
}, lattices.at(0));
uint64_t lattice_steps = 32;
bool even_step = true;
for(uint64_t step = 0; step < lattice_steps; ++step){
uint64_t old_lattice_index = even_step ? 0 : 1;
uint64_t new_lattice_index = even_step ? 1 : 0;
lbm_step(lattices.at(old_lattice_index), lattices.at(new_lattice_index));
even_step = !even_step;
}
/**
* Flush cout
*/
std::cout<<"\n\n";
std::cout.flush();
return 0;
}
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