WarpX class : em_solver_medium no longer a static variable (#5642)

This PR turns the static variable `em_solver_medium` of the WarpX class
into a private non-static member variable : `m_em_solver_medium` . This
is done with the aim of reducing the usage of static variables in WarpX.

Author: lucafedeli88

Source/Evolve/WarpXEvolve.cpp

@@ -438,10 +438,10 @@ WarpX::OneStep_nosub (Real cur_time)
         EvolveB(0.5_rt * dt[0], DtType::FirstHalf, cur_time); // We now have B^{n+1/2}
         FillBoundaryB(guard_cells.ng_FieldSolver, WarpX::sync_nodal_points);
 
-        if (WarpX::em_solver_medium == MediumForEM::Vacuum) {
+        if (m_em_solver_medium == MediumForEM::Vacuum) {
             // vacuum medium
             EvolveE(dt[0], cur_time); // We now have E^{n+1}
-        } else if (WarpX::em_solver_medium == MediumForEM::Macroscopic) {
+        } else if (m_em_solver_medium == MediumForEM::Macroscopic) {
             // macroscopic medium
             MacroscopicEvolveE(dt[0], cur_time); // We now have E^{n+1}
         } else {

Source/Initialization/WarpXInitData.cpp

@@ -288,17 +288,17 @@ WarpX::PrintMainPICparameters ()
     else{
       amrex::Print() << "Operation mode:       | Electromagnetic" << "\n";
     }
-    if (em_solver_medium == MediumForEM::Vacuum ){
+    if (m_em_solver_medium == MediumForEM::Vacuum ){
       amrex::Print() << "                      | - vacuum" << "\n";
     }
-    else if (em_solver_medium == MediumForEM::Macroscopic ){
+    else if (m_em_solver_medium == MediumForEM::Macroscopic ){
       amrex::Print() << "                      | - macroscopic" << "\n";
     }
-    if ( (em_solver_medium == MediumForEM::Macroscopic) &&
+    if ( (m_em_solver_medium == MediumForEM::Macroscopic) &&
        (WarpX::macroscopic_solver_algo == MacroscopicSolverAlgo::LaxWendroff)){
       amrex::Print() << "                      |  - Lax-Wendroff algorithm\n";
     }
-    else if ((em_solver_medium == MediumForEM::Macroscopic) &&
+    else if ((m_em_solver_medium == MediumForEM::Macroscopic) &&
             (WarpX::macroscopic_solver_algo == MacroscopicSolverAlgo::BackwardEuler)){
       amrex::Print() << "                      |  - Backward Euler algorithm\n";
     }
@@ -561,7 +561,7 @@ WarpX::InitData ()
 
     BuildBufferMasks();
 
-    if (WarpX::em_solver_medium == MediumForEM::Macroscopic) {
+    if (m_em_solver_medium == MediumForEM::Macroscopic) {
         const int lev_zero = 0;
         m_macroscopic_properties->InitData(
             Geom(lev_zero),

Source/Utils/WarpXMovingWindow.cpp

@@ -464,7 +464,7 @@ WarpX::MoveWindow (const int step, bool move_j)
     }
 
     // Recompute macroscopic properties of the medium
-    if (WarpX::em_solver_medium == MediumForEM::Macroscopic) {
+    if (m_em_solver_medium == MediumForEM::Macroscopic) {
         const int lev_zero = 0;
         m_macroscopic_properties->InitData(
             Geom(lev_zero),

Source/WarpX.H

@@ -206,8 +206,6 @@ public:
      *  being used (0 or 1 corresponding to timers or heuristic).
      */
     static inline auto load_balance_costs_update_algo = LoadBalanceCostsUpdateAlgo::Default;
-    //! Integer that corresponds to electromagnetic Maxwell solver (vacuum - 0, macroscopic - 1)
-    static inline auto em_solver_medium = MediumForEM::Default;
     /** Integer that correspond to macroscopic Maxwell solver algorithm
      *  (BackwardEuler - 0, Lax-Wendroff - 1)
      */
@@ -1371,6 +1369,9 @@ private:
     bool do_fluid_species = false;
     std::unique_ptr<MultiFluidContainer> myfl;
 
+    //! Integer that corresponds to electromagnetic Maxwell solver (vacuum - 0, macroscopic - 1)
+    MediumForEM m_em_solver_medium = MediumForEM::Default;
+
     //
     // Fields: First array for level, second for direction
     //

Source/WarpX.cpp

@@ -352,7 +352,7 @@ WarpX::WarpX ()
 
     m_field_factory.resize(nlevs_max);
 
-    if (em_solver_medium == MediumForEM::Macroscopic) {
+    if (m_em_solver_medium == MediumForEM::Macroscopic) {
         // create object for macroscopic solver
         m_macroscopic_properties = std::make_unique<MacroscopicProperties>();
     }
@@ -1248,8 +1248,8 @@ WarpX::ReadParameters ()
                 " combined with mesh refinement is currently not implemented");
         }
 
-        pp_algo.query_enum_sloppy("em_solver_medium", em_solver_medium, "-_");
-        if (em_solver_medium == MediumForEM::Macroscopic ) {
+        pp_algo.query_enum_sloppy("em_solver_medium", m_em_solver_medium, "-_");
+        if (m_em_solver_medium == MediumForEM::Macroscopic ) {
             pp_algo.query_enum_sloppy("macroscopic_sigma_method",
                                       macroscopic_solver_algo, "-_");
         }
@@ -2274,7 +2274,7 @@ WarpX::AllocLevelMFs (int lev, const BoxArray& ba, const DistributionMapping& dm
     }
 
     // Allocate extra multifabs for macroscopic properties of the medium
-    if (em_solver_medium == MediumForEM::Macroscopic) {
+    if (m_em_solver_medium == MediumForEM::Macroscopic) {
         WARPX_ALWAYS_ASSERT_WITH_MESSAGE( lev==0,
             "Macroscopic properties are not supported with mesh refinement.");
         m_macroscopic_properties->AllocateLevelMFs(ba, dm, ngEB);