New interface for kick_extra

src/hydro/Default/hydro.h

@@ -194,14 +194,15 @@ __attribute__((always_inline)) INLINE static void hydro_predict_extra(
 __attribute__((always_inline))
     INLINE static void hydro_end_force(struct part* p) {}
 
+
+
 /**
  * @brief Kick the additional variables
  *
  * @param p The particle to act upon
- * @param dt The time-step for this kick
  */
 __attribute__((always_inline))
-    INLINE static void hydro_kick_extra(struct part* p, float dt) {}
+   INLINE static void hydro_kick_extra(struct part* p, float dt) {}
 
 /**
  * @brief Converts hydro quantity of a particle

src/hydro/Gadget2/hydro.h

@@ -190,13 +190,18 @@ __attribute__((always_inline))
       (const_hydro_gamma - 1.f) * powf(p->rho, -(const_hydro_gamma - 1.f));
 }
 
+
 /**
  * @brief Kick the additional variables
  *
  * @param p The particle to act upon
+ * @param xp The particle extended data to act upon
+ * @param dt The time-step for this kick
+ * @param half_dt The half time-step for this kick
  */
 __attribute__((always_inline))
-    INLINE static void hydro_kick_extra(struct part* p, float dt) {
+    INLINE static void hydro_kick_extra(struct part* p, struct xpart* xp,
+					float dt, float half_dt) {
 
   /* Do not decrease the entropy (temperature) by more than a factor of 2*/
   const float entropy_change = p->entropy_dt * dt;

src/hydro/Minimal/hydro.h

@@ -156,10 +156,20 @@ __attribute__((always_inline))
  * @brief Kick the additional variables
  *
  * @param p The particle to act upon
+ * @param xp The particle extended data to act upon
  * @param dt The time-step for this kick
+ * @param half_dt The half time-step for this kick
  */
 __attribute__((always_inline))
-    INLINE static void hydro_kick_extra(struct part* p, float dt) {}
+    INLINE static void hydro_kick_extra(struct part* p, struct xpart* xp,
+					float dt, float half_dt) {
+
+  /* Kick in momentum space */
+  xp->u_full += p->u_dt * dt;
+
+  /* Get the predicted internal energy */
+  p->u = xp->u_full - half_dt * p->u_dt;
+}
 
 /**
  * @brief Converts hydro quantity of a particle

src/runner.c

@@ -930,7 +930,7 @@ void runner_dokick(struct runner *r, struct cell *c, int timer) {
         /* 	  p->v[2]); */
 
         /* Extra kick work */
-        hydro_kick_extra(p, dt);
+        hydro_kick_extra(p, xp, dt, half_dt);
       }
 
       /* Now collect quantities for statistics */