[tiny] Avoid particles with do_not_gather=1 be pushed in the last half step (#1210)

* species with do_not_gather=1 are not anymore pushed in the last halft step

* now do_not_gather is used just to avoid doing doGatherShapeN

* Minor fix

* fix involuntary capture of *this in lambda

1 files changed, 21 insertions, 14 deletions

diff --git a/Source/Particles/PhysicalParticleContainer.cpp b/Source/Particles/PhysicalParticleContainer.cpp
index 9511ab8f8..8c6959060 100644
--- a/Source/Particles/PhysicalParticleContainer.cpp
+++ b/Source/Particles/PhysicalParticleContainer.cpp
@@ -1474,6 +1474,8 @@ PhysicalParticleContainer::PushP (int lev, Real dt,
             const auto pusher_algo = WarpX::particle_pusher_algo;
             const auto do_crr = do_classical_radiation_reaction;
 
+            const auto t_do_not_gather = do_not_gather;
+
             amrex::ParallelFor( np, [=] AMREX_GPU_DEVICE (long ip)
             {
                 amrex::ParticleReal xp, yp, zp;
@@ -1485,12 +1487,14 @@ PhysicalParticleContainer::PushP (int lev, Real dt,
                 amrex::ParticleReal Bxp = 0._rt, Byp = 0._rt, Bzp = 0._rt;
                 getExternalB(ip, Bxp, Byp, Bzp);
 
-                // first gather E and B to the particle positions
-                doGatherShapeN(xp, yp, zp, Exp, Eyp, Ezp, Bxp, Byp, Bzp,
-                               ex_arr, ey_arr, ez_arr, bx_arr, by_arr, bz_arr,
-                               ex_type, ey_type, ez_type, bx_type, by_type, bz_type,
-                               dx_arr, xyzmin_arr, lo, n_rz_azimuthal_modes,
-                               nox, l_lower_order_in_v);
+                if (!t_do_not_gather){
+                    // first gather E and B to the particle positions
+                    doGatherShapeN(xp, yp, zp, Exp, Eyp, Ezp, Bxp, Byp, Bzp,
+                                   ex_arr, ey_arr, ez_arr, bx_arr, by_arr, bz_arr,
+                                   ex_type, ey_type, ez_type, bx_type, by_type, bz_type,
+                                   dx_arr, xyzmin_arr, lo, n_rz_azimuthal_modes,
+                                   nox, l_lower_order_in_v);
+                }
 
                 if (do_crr) {
                     amrex::Real qp = q;
@@ -1760,8 +1764,7 @@ PhysicalParticleContainer::PushPX (WarpXParIter& pti,
                                      (gather_lev==(lev  )),
                                      "Gather buffers only work for lev-1");
     // If no particles, do not do anything
-    // If do_not_gather = 1 by user, do not do anything
-    if (np_to_push == 0 || do_not_gather) return;
+    if (np_to_push == 0) return;
 
     // Get cell size on gather_lev
     const std::array<Real,3>& dx = WarpX::CellSize(std::max(gather_lev,0));
@@ -1850,6 +1853,8 @@ PhysicalParticleContainer::PushPX (WarpXParIter& pti,
     }
 #endif
 
+    const auto t_do_not_gather = do_not_gather;
+
     amrex::ParallelFor( np_to_push, [=] AMREX_GPU_DEVICE (long ip)
     {
         amrex::ParticleReal xp, yp, zp;
@@ -1861,12 +1866,14 @@ PhysicalParticleContainer::PushPX (WarpXParIter& pti,
         amrex::ParticleReal Bxp = 0._rt, Byp = 0._rt, Bzp = 0._rt;
         getExternalB(ip, Bxp, Byp, Bzp);
 
-        // first gather E and B to the particle positions
-        doGatherShapeN(xp, yp, zp, Exp, Eyp, Ezp, Bxp, Byp, Bzp,
-                       ex_arr, ey_arr, ez_arr, bx_arr, by_arr, bz_arr,
-                       ex_type, ey_type, ez_type, bx_type, by_type, bz_type,
-                       dx_arr, xyzmin_arr, lo, n_rz_azimuthal_modes,
-                       nox, l_lower_order_in_v);
+        if(!t_do_not_gather){
+            // first gather E and B to the particle positions
+            doGatherShapeN(xp, yp, zp, Exp, Eyp, Ezp, Bxp, Byp, Bzp,
+                           ex_arr, ey_arr, ez_arr, bx_arr, by_arr, bz_arr,
+                           ex_type, ey_type, ez_type, bx_type, by_type, bz_type,
+                           dx_arr, xyzmin_arr, lo, n_rz_azimuthal_modes,
+                           nox, l_lower_order_in_v);
+        }
 
         scaleFields(xp, yp, zp, Exp, Eyp, Ezp, Bxp, Byp, Bzp);