Simulation: move responsibility of updating persistent data handles

This solver should not be responsible for updating the handles.

1 files changed, 63 insertions, 3 deletions

diff --git a/source/blender/simulation/intern/simulation_update.cc b/source/blender/simulation/intern/simulation_update.cc
index 7a748ee57d1..117a98d2285 100644
--- a/source/blender/simulation/intern/simulation_update.cc
+++ b/source/blender/simulation/intern/simulation_update.cc
@@ -17,6 +17,7 @@
 #include "SIM_simulation_update.hh"
 
 #include "BKE_customdata.h"
+#include "BKE_lib_id.h"
 #include "BKE_simulation.h"
 
 #include "DNA_scene_types.h"
@@ -29,6 +30,7 @@
 #include "BLI_listbase.h"
 #include "BLI_map.hh"
 #include "BLI_rand.h"
+#include "BLI_set.hh"
 #include "BLI_vector.hh"
 
 #include "particle_function.hh"
@@ -88,6 +90,54 @@ static void update_simulation_state_list(Simulation *simulation,
   add_missing_states(simulation, required_states);
 }
 
+static void update_persistent_data_handles(Simulation &simulation_orig,
+                                           const UsedPersistentData &used_persistent_data)
+{
+  Set<ID *> contained_ids;
+  Set<int> used_handles;
+
+  /* Remove handles that have been invalidated. */
+  LISTBASE_FOREACH_MUTABLE (
+      PersistentDataHandleItem *, handle_item, &simulation_orig.persistent_data_handles) {
+    if (handle_item->id == nullptr) {
+      BLI_remlink(&simulation_orig.persistent_data_handles, handle_item);
+      MEM_freeN(handle_item);
+      continue;
+    }
+    if (!used_persistent_data.used_ids().contains(handle_item->id)) {
+      id_us_min(handle_item->id);
+      BLI_remlink(&simulation_orig.persistent_data_handles, handle_item);
+      MEM_freeN(handle_item);
+      continue;
+    }
+    contained_ids.add_new(handle_item->id);
+    used_handles.add_new(handle_item->handle);
+  }
+
+  /* Add new handles that are not in the list yet. */
+  int next_handle = 0;
+  for (ID *id : used_persistent_data.used_ids()) {
+    if (contained_ids.contains(id)) {
+      continue;
+    }
+
+    /* Find the next available handle. */
+    while (used_handles.contains(next_handle)) {
+      next_handle++;
+    }
+    used_handles.add_new(next_handle);
+
+    PersistentDataHandleItem *handle_item = (PersistentDataHandleItem *)MEM_callocN(
+        sizeof(*handle_item), AT);
+    /* Cannot store const pointers in DNA. */
+    id_us_plus(id);
+    handle_item->id = id;
+    handle_item->handle = next_handle;
+
+    BLI_addtail(&simulation_orig.persistent_data_handles, handle_item);
+  }
+}
+
 void update_simulation_in_depsgraph(Depsgraph *depsgraph,
                                     Scene *scene_cow,
                                     Simulation *simulation_cow)
@@ -107,13 +157,23 @@ void update_simulation_in_depsgraph(Depsgraph *depsgraph,
   ResourceCollector resources;
   SimulationInfluences influences;
   RequiredStates required_states;
+  UsedPersistentData used_persistent_data;
+
+  collect_simulation_influences(
+      *simulation_cow, resources, influences, required_states, used_persistent_data);
+  update_persistent_data_handles(*simulation_orig, used_persistent_data);
 
-  collect_simulation_influences(*simulation_cow, resources, influences, required_states);
+  bke::PersistentDataHandleMap handle_map;
+  LISTBASE_FOREACH (
+      PersistentDataHandleItem *, handle_item, &simulation_orig->persistent_data_handles) {
+    ID *id_cow = DEG_get_evaluated_id(depsgraph, handle_item->id);
+    handle_map.add(handle_item->handle, *id_cow);
+  }
 
   if (current_frame == 1) {
     reinitialize_empty_simulation_states(simulation_orig, required_states);
 
-    initialize_simulation_states(*simulation_orig, *depsgraph, influences);
+    initialize_simulation_states(*simulation_orig, *depsgraph, influences, handle_map);
     simulation_orig->current_frame = 1;
 
     copy_states_to_cow(simulation_orig, simulation_cow);
@@ -122,7 +182,7 @@ void update_simulation_in_depsgraph(Depsgraph *depsgraph,
     update_simulation_state_list(simulation_orig, required_states);
 
     float time_step = 1.0f / 24.0f;
-    solve_simulation_time_step(*simulation_orig, *depsgraph, influences, time_step);
+    solve_simulation_time_step(*simulation_orig, *depsgraph, influences, handle_map, time_step);
     simulation_orig->current_frame = current_frame;
 
     copy_states_to_cow(simulation_orig, simulation_cow);