1 files changed, 38 insertions, 5 deletions
diff --git a/Source/Parallelization/GuardCellManager.H b/Source/Parallelization/GuardCellManager.H
index 2e1cebff8..34cf549cf 100644
--- a/Source/Parallelization/GuardCellManager.H
+++ b/Source/Parallelization/GuardCellManager.H
@@ -3,11 +3,33 @@
 
 #include <AMReX_IntVect.H>
 
+/**
+ * \brief This class computes and stores the number of guard cells needed for
+ * the allocation of the MultiFabs and required for each part of the PIC loop.
+ */
 class guardCellManager{
 
 public:
 
-    int Init(
+    /**
+     * \brief Initialize number of guard cells depending on the options used.
+     *
+     * \param do_subcycling bool, whether to use subcycling
+     * \param do_fdtd_nci_corr bool, whether to use Godfrey NCI corrector
+     * \param do_nodal bool, whether the field solver is nodal
+     * \param do_moving_window bool, whether to use moving window
+     * \param do_fft_mpi_dec bool, whether to do parallel FFTs for PSATD
+     * \param aux_is_nodal bool, true if the aux grid is nodal
+     * \param moving_window_dir direction of moving window
+     * \param nox order of current deposition
+     * \param nox_fft order of PSATD in x direction
+     * \param noy_fft order of PSATD in y direction
+     * \param noz_fft order of PSATD in z direction
+     * \param nci_corr_stencil stencil of NCI corrector
+     * \param maxwell_fdtd_solver_id if of Maxwell solver
+     * \param max_level max level of the simulation
+     */
+    void Init(
         const bool do_subcycling,
         const bool do_fdtd_nci_corr,
         const bool do_nodal,
@@ -21,21 +43,32 @@ public:
         const int maxwell_fdtd_solver_id,
         const int max_level);
 
-    // Guard cells allocated for each multifab
+    // Guard cells allocated for MultiFabs E and B
     amrex::IntVect ng_alloc_EB = amrex::IntVect::TheZeroVector();
+    // Guard cells allocated for MultiFab J
     amrex::IntVect ng_alloc_J = amrex::IntVect::TheZeroVector();
+    // Guard cells allocated for MultiFab Rho
     amrex::IntVect ng_alloc_Rho = amrex::IntVect::TheZeroVector();
+    // Guard cells allocated for MultiFab F
     amrex::IntVect ng_alloc_F = amrex::IntVect::TheZeroVector();
-    int ng_alloc_F_int = 0;
 
-    // Guard cells exchanged for specific in the PIC loop
+    // Guard cells exchanged for specific parts of the PIC loop
+
+    // Number of guard cells of E and B that must exchanged before Field Solver
     amrex::IntVect ng_FieldSolver = amrex::IntVect::TheZeroVector();
+    // Number of guard cells of F that must exchanged before Field Solver
     amrex::IntVect ng_FieldSolverF = amrex::IntVect::TheZeroVector();
+    // Number of guard cells of E and B that must exchanged before Field Gather
     amrex::IntVect ng_FieldGather = amrex::IntVect::TheZeroVector();
+    // Number of guard cells of E and B that must exchanged before updating the Aux grid
     amrex::IntVect ng_UpdateAux = amrex::IntVect::TheZeroVector();
+    // Number of guard cells of all MultiFabs that must exchanged before moving window
     amrex::IntVect ng_MovingWindow = amrex::IntVect::TheZeroVector();
 
-    // Extra guard cells for fine level of E and B
+    // When the auxiliary grid is nodal but the field solver is staggered
+    // (typically with momentum-conserving gather with FDTD Yee solver),
+    // An extra guard cell is needed on the fine grid to do the interpolation
+    // for E and B.
     amrex::IntVect ng_Extra = amrex::IntVect::TheZeroVector();
 };