First initalisation of particles now happens in space_init() and not in...

First initalisation of particles now happens in space_init() and not in engine_init_particles() any more.

src/engine.c

@@ -2276,17 +2276,7 @@ void engine_init_particles(struct engine *e, int flag_entropy_ICs) {
   struct clocks_time time1, time2;
   clocks_gettime(&time1);
 
-  if (e->nodeID == 0) message("Initialising particles");
-
-  /* Make sure all particles are ready to go */
-  /* i.e. clean-up any stupid state in the ICs */
-  if (e->policy & engine_policy_hydro) {
-    space_map_cells_pre(s, 0, cell_init_parts, NULL);
-  }
-  if ((e->policy & engine_policy_self_gravity) ||
-      (e->policy & engine_policy_external_gravity)) {
-    space_map_cells_pre(s, 0, cell_init_gparts, NULL);
-  }
+  if (e->nodeID == 0) message("Running initialisation fake time-step.");
 
   engine_prepare(e);
 

src/gravity/Default/gravity.h

@@ -76,7 +76,11 @@ gravity_compute_timestep_self(const struct phys_const* const phys_const,
  * @param gp The particle to act upon
  */
 __attribute__((always_inline)) INLINE static void gravity_first_init_gpart(
-    struct gpart* gp) {}
+    struct gpart* gp) {
+
+  gp->ti_begin = 0;
+  gp->ti_end = 0;
+}
 
 /**
  * @brief Prepares a g-particle for the gravity calculation

src/hydro/Default/hydro.h

@@ -57,7 +57,15 @@ __attribute__((always_inline)) INLINE static float hydro_compute_timestep(
  * @param xp The extended particle data to act upon
  */
 __attribute__((always_inline)) INLINE static void hydro_first_init_part(
-    struct part *restrict p, struct xpart *restrict xp) {}
+    struct part *restrict p, struct xpart *restrict xp) {
+
+  p->ti_begin = 0;
+  p->ti_end = 0;
+  xp->v_full[0] = p->v[0];
+  xp->v_full[1] = p->v[1];
+  xp->v_full[2] = p->v[2];
+  xp->u_full = p->u;
+}
 
 /**
  * @brief Prepares a particle for the density calculation.

src/hydro/Gadget2/hydro.h

@@ -49,7 +49,14 @@ __attribute__((always_inline)) INLINE static float hydro_compute_timestep(
  * @param xp The extended particle data to act upon
  */
 __attribute__((always_inline)) INLINE static void hydro_first_init_part(
-    struct part *restrict p, struct xpart *restrict xp) {}
+    struct part *restrict p, struct xpart *restrict xp) {
+
+  p->ti_begin = 0;
+  p->ti_end = 0;
+  xp->v_full[0] = p->v[0];
+  xp->v_full[1] = p->v[1];
+  xp->v_full[2] = p->v[2];
+}
 
 /**
  * @brief Prepares a particle for the density calculation.

src/hydro/Minimal/hydro.h

@@ -57,6 +57,11 @@ __attribute__((always_inline)) INLINE static float hydro_compute_timestep(
 __attribute__((always_inline)) INLINE static void hydro_first_init_part(
     struct part *restrict p, struct xpart *restrict xp) {
 
+  p->ti_begin = 0;
+  p->ti_end = 0;
+  xp->v_full[0] = p->v[0];
+  xp->v_full[1] = p->v[1];
+  xp->v_full[2] = p->v[2];
   xp->u_full = p->u;
 }
 

src/space.c

@@ -43,6 +43,8 @@
 #include "atomic.h"
 #include "engine.h"
 #include "error.h"
+#include "gravity.h"
+#include "hydro.h"
 #include "kernel_hydro.h"
 #include "lock.h"
 #include "minmax.h"
@@ -1410,6 +1412,23 @@ struct cell *space_getcell(struct space *s) {
   return c;
 }
 
+void space_init_parts(struct space *s) {
+
+  const size_t nr_parts = s->nr_parts;
+  struct part *restrict p = s->parts;
+  struct xpart *restrict xp = s->xparts;
+
+  for (size_t i = 0; i < nr_parts; ++i) hydro_first_init_part(&p[i], &xp[i]);
+}
+
+void space_init_gparts(struct space *s) {
+
+  const size_t nr_gparts = s->nr_gparts;
+  struct gpart *restrict gp = s->gparts;
+
+  for (size_t i = 0; i < nr_gparts; ++i) gravity_first_init_gpart(&gp[i]);
+}
+
 /**
  * @brief Split the space into cells given the array of particles.
  *
@@ -1541,6 +1560,10 @@ void space_init(struct space *s, const struct swift_params *params,
     bzero(s->xparts, Npart * sizeof(struct xpart));
   }
 
+  /* Set the particles in a state where they are ready for a run */
+  space_init_parts(s);
+  space_init_gparts(s);
+
   /* Init the space lock. */
   if (lock_init(&s->lock) != 0) error("Failed to create space spin-lock.");
 

src/space.h

@@ -159,6 +159,8 @@ void space_split(struct space *s, struct cell *cells, int verbose);
 void space_do_split(struct space *s, struct cell *c);
 void space_do_parts_sort();
 void space_do_gparts_sort();
+void space_init_parts(struct space *s);
+void space_init_gparts(struct space *s);
 void space_link_cleanup(struct space *s);
 void space_clean(struct space *s);