Documentation of the new function and added the new BH-related functions to the Default model.

src/black_holes/Default/black_holes.h

@@ -227,6 +227,32 @@ __attribute__((always_inline)) INLINE static void black_holes_reset_feedback(
 #endif
 }
 
+/**
+ * @brief Store the gravitational potential of a black hole by copying it from
+ * its #gpart friend.
+ *
+ * Nothing to do here.
+ *
+ * @param bp The black hole particle.
+ * @param gp The black hole's #gpart.
+ */
+__attribute__((always_inline)) INLINE static void
+black_holes_store_potential_in_bpart(struct bpart* bp, const struct gpart* gp) {
+}
+
+/**
+ * @brief Store the gravitational potential of a particle by copying it from
+ * its #gpart friend.
+ *
+ * Nothing to do here.
+ *
+ * @param p_data The black hole data of a gas particle.
+ * @param gp The black hole's #gpart.
+ */
+__attribute__((always_inline)) INLINE static void
+black_holes_store_potential_in_part(struct black_holes_part_data* p_data,
+                                    const struct gpart* gp) {}
+
 /**
  * @brief Initialise a BH particle that has just been seeded.
  *

src/black_holes/Default/black_holes_struct.h

@@ -41,6 +41,16 @@ black_holes_mark_part_as_not_swallowed(struct black_holes_part_data* p_data) {
   /* Nothing to do here: No swallowing in the default model */
 }
 
+/**
+ * @brief Reset the particle-carried potential at the start of a time-step.
+ *
+ * Nothing to do here.
+ *
+ * @param p_data The #part's black hole data.
+ */
+__attribute__((always_inline)) INLINE static void black_holes_init_potential(
+    struct black_holes_part_data* p_data) {}
+
 /**
  * @brief Update a given #part's BH data field to mark the particle has
  * having been been swallowed.

src/black_holes/EAGLE/black_holes_struct.h

@@ -61,6 +61,11 @@ black_holes_mark_part_as_not_swallowed(struct black_holes_part_data* p_data) {
   p_data->swallow_id = -1;
 }
 
+/**
+ * @brief Reset the particle-carried potential at the start of a time-step.
+ *
+ * @param p_data The #part's black hole data.
+ */
 __attribute__((always_inline)) INLINE static void black_holes_init_potential(
     struct black_holes_part_data* p_data) {
   p_data->potential = FLT_MAX;