Added functions to generate tables and evolve optical depth

1 files changed, 82 insertions, 2 deletions

diff --git a/Source/QED/BreitWheelerEngineWrapper.cpp b/Source/QED/BreitWheelerEngineWrapper.cpp
index b654cc9b0..72fe06d63 100644
--- a/Source/QED/BreitWheelerEngineWrapper.cpp
+++ b/Source/QED/BreitWheelerEngineWrapper.cpp
@@ -2,8 +2,6 @@
 //This file provides a wrapper aroud the breit_wheeler engine
 //provided by the PICSAR library
 
-using namespace picsar::multi_physics;
-
 // Functors ==================================
 
 // Initialization of the optical depth
@@ -16,13 +14,95 @@ BreitWheelerGetOpticalDepth::operator() () const
 }
 //____________________________________________
 
+// Evolution of the optical depth (returns true if
+// an event occurs)
+AMREX_GPU_DEVICE
+bool BreitWheelerEvolveOpticalDepth::operator()(
+    amrex::Real px, amrex::Real py, amrex::Real pz, 
+    amrex::Real ex, amrex::Real ey, amrex::Real ez,
+    amrex::Real bx, amrex::Real by, amrex::Real bz,
+    amrex::Real dt, amrex::Real& opt_depth) const
+{
+    bool has_event_happend = false;
+    amrex::Real dummy_lambda = 1.0;
+    amrex::Real unused_event_time = 0.0;
+
+    const auto table = picsar::multi_physics::lookup_1d<amrex::Real>
+        (innards->TTfunc_data.size(),
+         innards->TTfunc_coords.data(),
+         innards->TTfunc_data.data());
+
+    WarpXBreitWheelerWrapper::internal_evolve_opt_depth_and_determine_event(
+        px, py, pz,
+        ex, ey, ez,
+        bx, by, bz,
+        dt, opt_depth, 
+        has_event_happend, unused_event_time,
+        dummy_lambda, 
+        table,
+        innards->ctrl);
+
+    return has_event_happend;
+}
+
 // Factory class =============================
 
 BreitWheelerEngine::BreitWheelerEngine(){}
 
+//Builds the functor to initialize the optical depth
 BreitWheelerGetOpticalDepth BreitWheelerEngine::build_optical_depth_functor()
 {
     return BreitWheelerGetOpticalDepth();
 }
 
+//Builds the functor to evolve the optical depth
+BreitWheelerEvolveOpticalDepth BreitWheelerEngine::build_evolve_functor()
+{
+    AMREX_ALWAYS_ASSERT(lookup_tables_initialized);
+
+    return BreitWheelerEvolveOpticalDepth(&innards);         
+}
+    
+
+//Initializes the Lookup tables using the default settings 
+//provided by the library
+void BreitWheelerEngine::computes_lookup_tables_default()
+{
+    //A control parameters structure
+    //with the default values provided by the library
+    WarpXBreitWheelerWrapperCtrl ctrl_default;
+
+    computes_lookup_tables(ctrl_default);
+
+    lookup_tables_initialized = true;
+}
+
+bool BreitWheelerEngine::are_lookup_tables_initialized() const
+{
+    return lookup_tables_initialized;
+}
+
+//Private function which actually computes the lookup tables
+void BreitWheelerEngine::computes_lookup_tables(
+    WarpXBreitWheelerWrapperCtrl ctrl)
+{
+    //Lambda is not actually used if S.I. units are enabled
+    WarpXBreitWheelerWrapper bw_engine(std::move(DummyStruct()), 1.0, ctrl);
+    
+    bw_engine.compute_dN_dt_lookup_table();
+    //bw_engine.compute_cumulative_pair_table();
+
+    auto bw_innards_picsar = bw_engine.export_innards();  
+
+    //Copy data in a GPU-friendly data-structure
+    innards.ctrl = bw_innards_picsar.bw_ctrl;
+    innards.TTfunc_coords.assign(bw_innards_picsar.TTfunc_table_coords_ptr, 
+        bw_innards_picsar.TTfunc_table_coords_ptr + 
+        bw_innards_picsar.TTfunc_table_coords_how_many);
+    innards.TTfunc_data.assign(bw_innards_picsar.TTfunc_table_data_ptr,
+        bw_innards_picsar.TTfunc_table_data_ptr + 
+        bw_innards_picsar.TTfunc_table_data_how_many);
+    //____
+}
+
 //============================================