From f3f05daf11b6be97202750c0251060dc2f5a18f3 Mon Sep 17 00:00:00 2001
From: Hans Goudey <h.goudey@me.com>
Date: Tue, 11 Jul 2023 10:53:15 -0400
Subject: [PATCH] Cleanup: Remove unused "Simulation" data-block

This data-block was originally added in eb4e3bbe68c8fb1d717d.
However, that original plan wasn't fully implemented, with simulations
now integrated with geometry nodes and modifiers instead of a separate
data-block. We kept the data-block around anyway since we have the
loose plan of using a similar data-block to make global simulations
connected between multiple objects. But it may be a while before we
implement that, and in the meantime having this just causes confusion.
---
 source/blender/CMakeLists.txt                 |   2 -
 source/blender/blenkernel/BKE_idtype.h        |   1 -
 source/blender/blenkernel/BKE_main.h          |   1 -
 source/blender/blenkernel/BKE_node.h          |   1 -
 source/blender/blenkernel/BKE_simulation.h    |  24 ---
 source/blender/blenkernel/CMakeLists.txt      |   2 -
 source/blender/blenkernel/intern/anim_data.c  |   6 -
 source/blender/blenkernel/intern/anim_sys.c   |   3 -
 source/blender/blenkernel/intern/idtype.c     |   5 -
 source/blender/blenkernel/intern/image.cc     |   6 -
 .../blender/blenkernel/intern/lib_override.cc |   7 +-
 source/blender/blenkernel/intern/lib_query.c  |   2 -
 source/blender/blenkernel/intern/main.c       |   3 -
 source/blender/blenkernel/intern/node.cc      |   9 -
 source/blender/blenkernel/intern/pointcache.c |   1 -
 .../blender/blenkernel/intern/simulation.cc   | 192 ------------------
 source/blender/blenloader/intern/readfile.cc  |   2 -
 .../blender/depsgraph/DEG_depsgraph_build.h   |   4 -
 .../intern/builder/deg_builder_nodes.cc       |  27 ---
 .../intern/builder/deg_builder_nodes.h        |   2 -
 .../intern/builder/deg_builder_relations.cc   |  29 ---
 .../intern/builder/deg_builder_relations.h    |   2 -
 .../debug/deg_debug_relations_graphviz.cc     |   3 +-
 .../depsgraph/intern/depsgraph_build.cc       |  11 -
 .../blender/depsgraph/intern/depsgraph_tag.cc |   1 -
 .../intern/eval/deg_eval_copy_on_write.cc     |   6 -
 .../blender/depsgraph/intern/node/deg_node.cc |   4 -
 .../blender/depsgraph/intern/node/deg_node.h  |   2 -
 .../intern/node/deg_node_component.cc         |   2 -
 .../intern/node/deg_node_operation.cc         |   2 -
 .../intern/node/deg_node_operation.h          |   3 -
 .../animation/anim_channels_defines.cc        |  80 --------
 .../blender/editors/animation/anim_filter.cc  |  13 --
 source/blender/editors/include/ED_anim_api.h  |   2 -
 .../editors/interface/interface_icons.cc      |   3 -
 .../editors/interface/interface_templates.cc  |   5 +-
 .../blender/editors/render/render_opengl.cc   |   1 -
 .../editors/space_outliner/outliner_draw.cc   |   3 -
 .../editors/space_outliner/outliner_intern.hh |   1 -
 .../editors/space_outliner/outliner_tools.cc  |   2 -
 .../space_outliner/tree/tree_element_id.cc    |   1 -
 source/blender/makesdna/DNA_ID.h              |   1 -
 source/blender/makesdna/DNA_ID_enums.h        |   1 -
 .../blender/makesdna/DNA_simulation_types.h   |  38 ----
 source/blender/makesdna/intern/dna_defaults.c |   8 -
 source/blender/makesrna/intern/CMakeLists.txt |   1 -
 source/blender/makesrna/intern/makesrna.c     |   3 -
 source/blender/makesrna/intern/rna_ID.c       |  17 --
 source/blender/makesrna/intern/rna_ID.cc      |  17 --
 source/blender/makesrna/intern/rna_internal.h |   3 -
 source/blender/makesrna/intern/rna_main.cc    |  11 -
 .../blender/makesrna/intern/rna_main_api.cc   |  62 ------
 .../blender/makesrna/intern/rna_simulation.cc |  46 -----
 source/blender/modifiers/intern/MOD_nodes.cc  |   1 -
 54 files changed, 7 insertions(+), 678 deletions(-)
 delete mode 100644 source/blender/blenkernel/BKE_simulation.h
 delete mode 100644 source/blender/blenkernel/intern/simulation.cc
 delete mode 100644 source/blender/makesdna/DNA_simulation_types.h
 delete mode 100644 source/blender/makesrna/intern/rna_simulation.cc

diff --git a/source/blender/CMakeLists.txt b/source/blender/CMakeLists.txt
index 3f0fc409a44..b8c18d6929a 100644
--- a/source/blender/CMakeLists.txt
+++ b/source/blender/CMakeLists.txt
@@ -70,7 +70,6 @@ set(SRC_DNA_INC
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_sequence_types.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_session_uuid_types.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_shader_fx_types.h
-  ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_simulation_types.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_sound_types.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_space_types.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_speaker_types.h
@@ -119,7 +118,6 @@ set(SRC_DNA_DEFAULTS_INC
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_particle_defaults.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_pointcloud_defaults.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_scene_defaults.h
-  ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_simulation_defaults.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_space_defaults.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_speaker_defaults.h
   ${CMAKE_CURRENT_SOURCE_DIR}/makesdna/DNA_texture_defaults.h
diff --git a/source/blender/blenkernel/BKE_idtype.h b/source/blender/blenkernel/BKE_idtype.h
index e7f0c137678..6e0d14e695e 100644
--- a/source/blender/blenkernel/BKE_idtype.h
+++ b/source/blender/blenkernel/BKE_idtype.h
@@ -277,7 +277,6 @@ extern IDTypeInfo IDType_ID_LP;
 extern IDTypeInfo IDType_ID_CV;
 extern IDTypeInfo IDType_ID_PT;
 extern IDTypeInfo IDType_ID_VO;
-extern IDTypeInfo IDType_ID_SIM;
 extern IDTypeInfo IDType_ID_GP;
 
 /** Empty shell mostly, but needed for read code. */
diff --git a/source/blender/blenkernel/BKE_main.h b/source/blender/blenkernel/BKE_main.h
index fcea5e67d59..c75d16ac7c6 100644
--- a/source/blender/blenkernel/BKE_main.h
+++ b/source/blender/blenkernel/BKE_main.h
@@ -225,7 +225,6 @@ typedef struct Main {
   ListBase hair_curves;
   ListBase pointclouds;
   ListBase volumes;
-  ListBase simulations;
 
   /**
    * Must be generated, used and freed by same code - never assume this is valid data unless you
diff --git a/source/blender/blenkernel/BKE_node.h b/source/blender/blenkernel/BKE_node.h
index 9853ac05dcf..2fdb19299aa 100644
--- a/source/blender/blenkernel/BKE_node.h
+++ b/source/blender/blenkernel/BKE_node.h
@@ -880,7 +880,6 @@ struct NodeTreeIterStore {
   struct Light *light;
   struct World *world;
   struct FreestyleLineStyle *linestyle;
-  struct Simulation *simulation;
 };
 
 void BKE_node_tree_iter_init(struct NodeTreeIterStore *ntreeiter, struct Main *bmain);
diff --git a/source/blender/blenkernel/BKE_simulation.h b/source/blender/blenkernel/BKE_simulation.h
deleted file mode 100644
index 489c4288ec9..00000000000
--- a/source/blender/blenkernel/BKE_simulation.h
+++ /dev/null
@@ -1,24 +0,0 @@
-/* SPDX-FileCopyrightText: 2023 Blender Foundation
- *
- * SPDX-License-Identifier: GPL-2.0-or-later */
-
-#pragma once
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-struct Depsgraph;
-struct Main;
-struct Scene;
-struct Simulation;
-
-void *BKE_simulation_add(struct Main *bmain, const char *name);
-
-void BKE_simulation_data_update(struct Depsgraph *depsgraph,
-                                struct Scene *scene,
-                                struct Simulation *simulation);
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index d010733a435..28be13ceb1a 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -264,7 +264,6 @@ set(SRC
   intern/screen.c
   intern/shader_fx.c
   intern/shrinkwrap.cc
-  intern/simulation.cc
   intern/simulation_state.cc
   intern/simulation_state_serialize.cc
   intern/softbody.c
@@ -471,7 +470,6 @@ set(SRC
   BKE_sequencer_offscreen.h
   BKE_shader_fx.h
   BKE_shrinkwrap.h
-  BKE_simulation.h
   BKE_simulation_state.hh
   BKE_simulation_state_serialize.hh
   BKE_softbody.h
diff --git a/source/blender/blenkernel/intern/anim_data.c b/source/blender/blenkernel/intern/anim_data.c
index 384ec4078b1..fa0ed56acf4 100644
--- a/source/blender/blenkernel/intern/anim_data.c
+++ b/source/blender/blenkernel/intern/anim_data.c
@@ -1313,9 +1313,6 @@ void BKE_animdata_main_cb(Main *bmain, ID_AnimData_Edit_Callback func, void *use
 
   /* volumes */
   ANIMDATA_IDS_CB(bmain->volumes.first);
-
-  /* simulations */
-  ANIMDATA_IDS_CB(bmain->simulations.first);
 }
 
 void BKE_animdata_fix_paths_rename_all(ID *ref_id,
@@ -1443,9 +1440,6 @@ void BKE_animdata_fix_paths_rename_all_ex(Main *bmain,
   /* volumes */
   RENAMEFIX_ANIM_IDS(bmain->volumes.first);
 
-  /* simulations */
-  RENAMEFIX_ANIM_IDS(bmain->simulations.first);
-
   /* scenes */
   RENAMEFIX_ANIM_NODETREE_IDS(bmain->scenes.first, Scene);
 }
diff --git a/source/blender/blenkernel/intern/anim_sys.c b/source/blender/blenkernel/intern/anim_sys.c
index f6f5f065de2..17b8d8f1325 100644
--- a/source/blender/blenkernel/intern/anim_sys.c
+++ b/source/blender/blenkernel/intern/anim_sys.c
@@ -4103,9 +4103,6 @@ void BKE_animsys_evaluate_all_animation(Main *main, Depsgraph *depsgraph, float
   /* volumes */
   EVAL_ANIM_IDS(main->volumes.first, ADT_RECALC_ANIM);
 
-  /* simulations */
-  EVAL_ANIM_IDS(main->simulations.first, ADT_RECALC_ANIM);
-
   /* objects */
   /* ADT_RECALC_ANIM doesn't need to be supplied here, since object AnimData gets
    * this tagged by Depsgraph on frame-change. This optimization means that objects
diff --git a/source/blender/blenkernel/intern/idtype.c b/source/blender/blenkernel/intern/idtype.c
index fbd94172bae..c19eed5a941 100644
--- a/source/blender/blenkernel/intern/idtype.c
+++ b/source/blender/blenkernel/intern/idtype.c
@@ -95,7 +95,6 @@ static void id_type_init(void)
   INIT_TYPE(ID_CV);
   INIT_TYPE(ID_PT);
   INIT_TYPE(ID_VO);
-  INIT_TYPE(ID_SIM);
   INIT_TYPE(ID_GP);
 
   /* Special naughty boy... */
@@ -248,7 +247,6 @@ uint64_t BKE_idtype_idcode_to_idfilter(const short idcode)
     CASE_IDFILTER(PT);
     CASE_IDFILTER(SCE);
     CASE_IDFILTER(SCR);
-    CASE_IDFILTER(SIM);
     CASE_IDFILTER(SO);
     CASE_IDFILTER(SPK);
     CASE_IDFILTER(TE);
@@ -307,7 +305,6 @@ short BKE_idtype_idcode_from_idfilter(const uint64_t idfilter)
     CASE_IDFILTER(PT);
     CASE_IDFILTER(SCE);
     CASE_IDFILTER(SCR);
-    CASE_IDFILTER(SIM);
     CASE_IDFILTER(SO);
     CASE_IDFILTER(SPK);
     CASE_IDFILTER(TE);
@@ -364,7 +361,6 @@ int BKE_idtype_idcode_to_index(const short idcode)
     CASE_IDINDEX(LP);
     CASE_IDINDEX(SCE);
     CASE_IDINDEX(SCR);
-    CASE_IDINDEX(SIM);
     CASE_IDINDEX(SPK);
     CASE_IDINDEX(SO);
     CASE_IDINDEX(TE);
@@ -424,7 +420,6 @@ short BKE_idtype_idcode_from_index(const int index)
     CASE_IDCODE(LP);
     CASE_IDCODE(SCE);
     CASE_IDCODE(SCR);
-    CASE_IDCODE(SIM);
     CASE_IDCODE(SPK);
     CASE_IDCODE(SO);
     CASE_IDCODE(TE);
diff --git a/source/blender/blenkernel/intern/image.cc b/source/blender/blenkernel/intern/image.cc
index 3850c11b371..c3ab70a2b1b 100644
--- a/source/blender/blenkernel/intern/image.cc
+++ b/source/blender/blenkernel/intern/image.cc
@@ -49,7 +49,6 @@
 #include "DNA_packedFile_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_world_types.h"
 
 #include "BLI_blenlib.h"
@@ -2881,11 +2880,6 @@ static void image_walk_id_all_users(
       }
       break;
     }
-    case ID_SIM: {
-      Simulation *simulation = (Simulation *)id;
-      image_walk_ntree_all_users(simulation->nodetree, &simulation->id, customdata, callback);
-      break;
-    }
     default:
       break;
   }
diff --git a/source/blender/blenkernel/intern/lib_override.cc b/source/blender/blenkernel/intern/lib_override.cc
index e93b2773a75..ac72d8701cc 100644
--- a/source/blender/blenkernel/intern/lib_override.cc
+++ b/source/blender/blenkernel/intern/lib_override.cc
@@ -276,9 +276,12 @@ static ID *lib_override_library_create_from(Main *bmain,
                                 LIB_ID_COPY_DEFAULT | LIB_ID_COPY_NO_LIB_OVERRIDE |
                                     lib_id_copy_flags);
 
-  /* Incase we could not get an override ID with the exact same name as its linked reference, ensure we at least get a uniquely named override ID over the whole current Main data, to reduce potential name collisions with other reference IDs.
+  /* Incase we could not get an override ID with the exact same name as its linked reference,
+   * ensure we at least get a uniquely named override ID over the whole current Main data, to
+   * reduce potential name collisions with other reference IDs.
    *
-   * While in normal cases this would not be an issue, when files start to get heavily broken and not sound, such conflicts can become a source of problems. */
+   * While in normal cases this would not be an issue, when files start to get heavily broken and
+   * not sound, such conflicts can become a source of problems. */
   if (!STREQ(local_id->name + 2, reference_id->name + 2)) {
     BLI_strncpy(local_id->name + 2, reference_id->name + 2, MAX_ID_NAME - 2);
     BKE_main_namemap_get_name(bmain, local_id, local_id->name + 2, true);
diff --git a/source/blender/blenkernel/intern/lib_query.c b/source/blender/blenkernel/intern/lib_query.c
index 1e677e10942..476e598928a 100644
--- a/source/blender/blenkernel/intern/lib_query.c
+++ b/source/blender/blenkernel/intern/lib_query.c
@@ -475,8 +475,6 @@ uint64_t BKE_library_id_can_use_filter_id(const ID *owner_id, const bool include
       return FILTER_ID_MA;
     case ID_VO:
       return FILTER_ID_MA;
-    case ID_SIM:
-      return FILTER_ID_OB | FILTER_ID_IM;
     case ID_WM:
       return FILTER_ID_SCE | FILTER_ID_WS;
     case ID_IM:
diff --git a/source/blender/blenkernel/intern/main.c b/source/blender/blenkernel/intern/main.c
index a2dd0b99b0b..7e3741a9d2f 100644
--- a/source/blender/blenkernel/intern/main.c
+++ b/source/blender/blenkernel/intern/main.c
@@ -597,8 +597,6 @@ ListBase *which_libbase(Main *bmain, short type)
       return &(bmain->pointclouds);
     case ID_VO:
       return &(bmain->volumes);
-    case ID_SIM:
-      return &(bmain->simulations);
   }
   return NULL;
 }
@@ -664,7 +662,6 @@ int set_listbasepointers(Main *bmain, ListBase *lb[/*INDEX_ID_MAX*/])
   lb[INDEX_ID_WS] = &(bmain->workspaces); /* before wm, so it's freed after it! */
   lb[INDEX_ID_WM] = &(bmain->wm);
   lb[INDEX_ID_MSK] = &(bmain->masks);
-  lb[INDEX_ID_SIM] = &(bmain->simulations);
 
   lb[INDEX_ID_NULL] = NULL;
 
diff --git a/source/blender/blenkernel/intern/node.cc b/source/blender/blenkernel/intern/node.cc
index 38e343f8894..e1d337e3055 100644
--- a/source/blender/blenkernel/intern/node.cc
+++ b/source/blender/blenkernel/intern/node.cc
@@ -28,7 +28,6 @@
 #include "DNA_modifier_types.h"
 #include "DNA_node_types.h"
 #include "DNA_scene_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_texture_types.h"
 #include "DNA_world_types.h"
 
@@ -3594,8 +3593,6 @@ bNodeTree **BKE_ntree_ptr_from_id(ID *id)
       return &reinterpret_cast<Scene *>(id)->nodetree;
     case ID_LS:
       return &reinterpret_cast<FreestyleLineStyle *>(id)->nodetree;
-    case ID_SIM:
-      return &reinterpret_cast<Simulation *>(id)->nodetree;
     default:
       return nullptr;
   }
@@ -4726,7 +4723,6 @@ void BKE_node_tree_iter_init(NodeTreeIterStore *ntreeiter, Main *bmain)
   ntreeiter->light = (Light *)bmain->lights.first;
   ntreeiter->world = (World *)bmain->worlds.first;
   ntreeiter->linestyle = (FreestyleLineStyle *)bmain->linestyles.first;
-  ntreeiter->simulation = (Simulation *)bmain->simulations.first;
 }
 bool BKE_node_tree_iter_step(NodeTreeIterStore *ntreeiter, bNodeTree **r_nodetree, ID **r_id)
 {
@@ -4766,11 +4762,6 @@ bool BKE_node_tree_iter_step(NodeTreeIterStore *ntreeiter, bNodeTree **r_nodetre
     *r_id = &ntreeiter->linestyle->id;
     ntreeiter->linestyle = reinterpret_cast<FreestyleLineStyle *>(ntreeiter->linestyle->id.next);
   }
-  else if (ntreeiter->simulation) {
-    *r_nodetree = reinterpret_cast<bNodeTree *>(ntreeiter->simulation->nodetree);
-    *r_id = &ntreeiter->simulation->id;
-    ntreeiter->simulation = reinterpret_cast<Simulation *>(ntreeiter->simulation->id.next);
-  }
   else {
     return false;
   }
diff --git a/source/blender/blenkernel/intern/pointcache.c b/source/blender/blenkernel/intern/pointcache.c
index a29ca367931..b81b66541db 100644
--- a/source/blender/blenkernel/intern/pointcache.c
+++ b/source/blender/blenkernel/intern/pointcache.c
@@ -26,7 +26,6 @@
 #include "DNA_particle_types.h"
 #include "DNA_rigidbody_types.h"
 #include "DNA_scene_types.h"
-#include "DNA_simulation_types.h"
 
 #include "BLI_blenlib.h"
 #include "BLI_endian_switch.h"
diff --git a/source/blender/blenkernel/intern/simulation.cc b/source/blender/blenkernel/intern/simulation.cc
deleted file mode 100644
index 3372aae1a61..00000000000
--- a/source/blender/blenkernel/intern/simulation.cc
+++ /dev/null
@@ -1,192 +0,0 @@
-/* SPDX-FileCopyrightText: 2023 Blender Foundation
- *
- * SPDX-License-Identifier: GPL-2.0-or-later */
-
-/** \file
- * \ingroup bke
- */
-
-#include <iostream>
-
-#include "MEM_guardedalloc.h"
-
-#include "DNA_ID.h"
-#include "DNA_defaults.h"
-#include "DNA_modifier_types.h"
-#include "DNA_scene_types.h"
-#include "DNA_simulation_types.h"
-
-#include "BLI_compiler_compat.h"
-#include "BLI_listbase.h"
-#include "BLI_math.h"
-#include "BLI_math_vector_types.hh"
-#include "BLI_rand.h"
-#include "BLI_span.hh"
-#include "BLI_string.h"
-#include "BLI_utildefines.h"
-
-#include "BKE_anim_data.h"
-#include "BKE_animsys.h"
-#include "BKE_collection.h"
-#include "BKE_customdata.h"
-#include "BKE_idtype.h"
-#include "BKE_lib_id.h"
-#include "BKE_lib_query.h"
-#include "BKE_lib_remap.h"
-#include "BKE_main.h"
-#include "BKE_modifier.h"
-#include "BKE_node.hh"
-#include "BKE_pointcache.h"
-#include "BKE_simulation.h"
-#include "BKE_simulation_state.hh"
-
-#include "NOD_geometry.hh"
-
-#include "BLI_map.hh"
-#include "BLT_translation.h"
-
-#include "DEG_depsgraph.h"
-#include "DEG_depsgraph_query.h"
-
-#include "MOD_nodes.hh"
-
-#include "BLO_read_write.h"
-
-static void simulation_init_data(ID *id)
-{
-  Simulation *simulation = (Simulation *)id;
-  BLI_assert(MEMCMP_STRUCT_AFTER_IS_ZERO(simulation, id));
-
-  MEMCPY_STRUCT_AFTER(simulation, DNA_struct_default_get(Simulation), id);
-
-  blender::bke::ntreeAddTreeEmbedded(nullptr, id, "Geometry Nodetree", ntreeType_Geometry->idname);
-}
-
-static void simulation_copy_data(Main *bmain, ID *id_dst, const ID *id_src, const int flag)
-{
-  Simulation *simulation_dst = (Simulation *)id_dst;
-  const Simulation *simulation_src = (const Simulation *)id_src;
-
-  /* We always need allocation of our private ID data. */
-  const int flag_private_id_data = flag & ~LIB_ID_CREATE_NO_ALLOCATE;
-
-  if (simulation_src->nodetree) {
-    BKE_id_copy_ex(bmain,
-                   (ID *)simulation_src->nodetree,
-                   (ID **)&simulation_dst->nodetree,
-                   flag_private_id_data);
-    simulation_dst->nodetree->owner_id = &simulation_dst->id;
-  }
-}
-
-static void simulation_free_data(ID *id)
-{
-  Simulation *simulation = (Simulation *)id;
-
-  BKE_animdata_free(&simulation->id, false);
-
-  if (simulation->nodetree) {
-    ntreeFreeEmbeddedTree(simulation->nodetree);
-    MEM_freeN(simulation->nodetree);
-    simulation->nodetree = nullptr;
-  }
-}
-
-static void simulation_foreach_id(ID *id, LibraryForeachIDData *data)
-{
-  Simulation *simulation = (Simulation *)id;
-  if (simulation->nodetree) {
-    /* nodetree **are owned by IDs**, treat them as mere sub-data and not real ID! */
-    BKE_LIB_FOREACHID_PROCESS_FUNCTION_CALL(
-        data, BKE_library_foreach_ID_embedded(data, (ID **)&simulation->nodetree));
-  }
-}
-
-static void simulation_blend_write(BlendWriter *writer, ID *id, const void *id_address)
-{
-  Simulation *simulation = (Simulation *)id;
-
-  BLO_write_id_struct(writer, Simulation, id_address, &simulation->id);
-  BKE_id_blend_write(writer, &simulation->id);
-
-  if (simulation->adt) {
-    BKE_animdata_blend_write(writer, simulation->adt);
-  }
-
-  /* nodetree is integral part of simulation, no libdata */
-  if (simulation->nodetree) {
-    BLO_Write_IDBuffer *temp_embedded_id_buffer = BLO_write_allocate_id_buffer();
-    BLO_write_init_id_buffer_from_id(
-        temp_embedded_id_buffer, &simulation->nodetree->id, BLO_write_is_undo(writer));
-    BLO_write_struct_at_address(writer,
-                                bNodeTree,
-                                simulation->nodetree,
-                                BLO_write_get_id_buffer_temp_id(temp_embedded_id_buffer));
-    ntreeBlendWrite(
-        writer,
-        reinterpret_cast<bNodeTree *>(BLO_write_get_id_buffer_temp_id(temp_embedded_id_buffer)));
-    BLO_write_destroy_id_buffer(&temp_embedded_id_buffer);
-  }
-}
-
-static void simulation_blend_read_data(BlendDataReader *reader, ID *id)
-{
-  Simulation *simulation = (Simulation *)id;
-  BLO_read_data_address(reader, &simulation->adt);
-  BKE_animdata_blend_read_data(reader, simulation->adt);
-}
-
-static void simulation_blend_read_lib(BlendLibReader *reader, ID *id)
-{
-  Simulation *simulation = (Simulation *)id;
-  UNUSED_VARS(simulation, reader);
-}
-
-static void simulation_blend_read_expand(BlendExpander *expander, ID *id)
-{
-  Simulation *simulation = (Simulation *)id;
-  UNUSED_VARS(simulation, expander);
-}
-
-IDTypeInfo IDType_ID_SIM = {
-    /*id_code*/ ID_SIM,
-    /*id_filter*/ FILTER_ID_SIM,
-    /*main_listbase_index*/ INDEX_ID_SIM,
-    /*struct_size*/ sizeof(Simulation),
-    /*name*/ "Simulation",
-    /*name_plural*/ "simulations",
-    /*translation_context*/ BLT_I18NCONTEXT_ID_SIMULATION,
-    /*flags*/ IDTYPE_FLAGS_APPEND_IS_REUSABLE,
-    /*asset_type_info*/ nullptr,
-
-    /*init_data*/ simulation_init_data,
-    /*copy_data*/ simulation_copy_data,
-    /*free_data*/ simulation_free_data,
-    /*make_local*/ nullptr,
-    /*foreach_id*/ simulation_foreach_id,
-    /*foreach_cache*/ nullptr,
-    /*foreach_path*/ nullptr,
-    /*owner_pointer_get*/ nullptr,
-
-    /*blend_write*/ simulation_blend_write,
-    /*blend_read_data*/ simulation_blend_read_data,
-    /*blend_read_lib*/ simulation_blend_read_lib,
-    /*blend_read_expand*/ simulation_blend_read_expand,
-
-    /*blend_read_undo_preserve*/ nullptr,
-
-    /*lib_override_apply_post*/ nullptr,
-};
-
-void *BKE_simulation_add(Main *bmain, const char *name)
-{
-  Simulation *simulation = (Simulation *)BKE_id_new(bmain, ID_SIM, name);
-  return simulation;
-}
-
-void BKE_simulation_data_update(Depsgraph * /*depsgraph*/,
-                                Scene * /*scene*/,
-                                Simulation * /*simulation*/)
-{
-}
-
diff --git a/source/blender/blenloader/intern/readfile.cc b/source/blender/blenloader/intern/readfile.cc
index 2354c174fa4..9daf90a09ee 100644
--- a/source/blender/blenloader/intern/readfile.cc
+++ b/source/blender/blenloader/intern/readfile.cc
@@ -2397,8 +2397,6 @@ static const char *dataname(short id_code)
       return "Data from PT";
     case ID_VO:
       return "Data from VO";
-    case ID_SIM:
-      return "Data from SIM";
     case ID_GP:
       return "Data from GP";
   }
diff --git a/source/blender/depsgraph/DEG_depsgraph_build.h b/source/blender/depsgraph/DEG_depsgraph_build.h
index f0e2c750ffc..0660d42a87a 100644
--- a/source/blender/depsgraph/DEG_depsgraph_build.h
+++ b/source/blender/depsgraph/DEG_depsgraph_build.h
@@ -24,7 +24,6 @@ struct ID;
 struct Main;
 struct Object;
 struct Scene;
-struct Simulation;
 struct bNodeTree;
 
 #include "BLI_sys_types.h"
@@ -135,9 +134,6 @@ void DEG_add_collection_geometry_relation(struct DepsNodeHandle *node_handle,
 void DEG_add_collection_geometry_customdata_mask(struct DepsNodeHandle *node_handle,
                                                  struct Collection *collection,
                                                  const struct CustomData_MeshMasks *masks);
-void DEG_add_simulation_relation(struct DepsNodeHandle *node_handle,
-                                 struct Simulation *simulation,
-                                 const char *description);
 void DEG_add_node_tree_output_relation(struct DepsNodeHandle *node_handle,
                                        struct bNodeTree *node_tree,
                                        const char *description);
diff --git a/source/blender/depsgraph/intern/builder/deg_builder_nodes.cc b/source/blender/depsgraph/intern/builder/deg_builder_nodes.cc
index cffa7e087a2..7e965a2e14e 100644
--- a/source/blender/depsgraph/intern/builder/deg_builder_nodes.cc
+++ b/source/blender/depsgraph/intern/builder/deg_builder_nodes.cc
@@ -45,7 +45,6 @@
 #include "DNA_rigidbody_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_sound_types.h"
 #include "DNA_speaker_types.h"
 #include "DNA_texture_types.h"
@@ -88,7 +87,6 @@
 #include "BKE_rigidbody.h"
 #include "BKE_scene.h"
 #include "BKE_shader_fx.h"
-#include "BKE_simulation.h"
 #include "BKE_simulation_state.hh"
 #include "BKE_sound.h"
 #include "BKE_tracking.h"
@@ -638,9 +636,6 @@ void DepsgraphNodeBuilder::build_id(ID *id)
     case ID_SCE:
       build_scene_parameters((Scene *)id);
       break;
-    case ID_SIM:
-      build_simulation((Simulation *)id);
-      break;
     case ID_PA:
       build_particle_settings((ParticleSettings *)id);
       break;
@@ -2148,28 +2143,6 @@ void DepsgraphNodeBuilder::build_sound(bSound *sound)
   build_parameters(&sound->id);
 }
 
-void DepsgraphNodeBuilder::build_simulation(Simulation *simulation)
-{
-  if (built_map_.checkIsBuiltAndTag(simulation)) {
-    return;
-  }
-  add_id_node(&simulation->id);
-  build_idproperties(simulation->id.properties);
-  build_animdata(&simulation->id);
-  build_parameters(&simulation->id);
-  build_nodetree(simulation->nodetree);
-
-  Simulation *simulation_cow = get_cow_datablock(simulation);
-  Scene *scene_cow = get_cow_datablock(scene_);
-
-  add_operation_node(&simulation->id,
-                     NodeType::SIMULATION,
-                     OperationCode::SIMULATION_EVAL,
-                     [scene_cow, simulation_cow](::Depsgraph *depsgraph) {
-                       BKE_simulation_data_update(depsgraph, scene_cow, simulation_cow);
-                     });
-}
-
 void DepsgraphNodeBuilder::build_vfont(VFont *vfont)
 {
   if (built_map_.checkIsBuiltAndTag(vfont)) {
diff --git a/source/blender/depsgraph/intern/builder/deg_builder_nodes.h b/source/blender/depsgraph/intern/builder/deg_builder_nodes.h
index 6d6896e9633..b90c60e5c05 100644
--- a/source/blender/depsgraph/intern/builder/deg_builder_nodes.h
+++ b/source/blender/depsgraph/intern/builder/deg_builder_nodes.h
@@ -38,7 +38,6 @@ struct MovieClip;
 struct Object;
 struct ParticleSettings;
 struct Scene;
-struct Simulation;
 struct Speaker;
 struct Tex;
 struct VFont;
@@ -263,7 +262,6 @@ class DepsgraphNodeBuilder : public DepsgraphBuilder {
   virtual void build_lightprobe(LightProbe *probe);
   virtual void build_speaker(Speaker *speaker);
   virtual void build_sound(bSound *sound);
-  virtual void build_simulation(Simulation *simulation);
   virtual void build_scene_sequencer(Scene *scene);
   virtual void build_scene_audio(Scene *scene);
   virtual void build_scene_speakers(Scene *scene, ViewLayer *view_layer);
diff --git a/source/blender/depsgraph/intern/builder/deg_builder_relations.cc b/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
index 9cbbfe9b802..9dfef815264 100644
--- a/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
+++ b/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
@@ -47,7 +47,6 @@
 #include "DNA_rigidbody_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_sound_types.h"
 #include "DNA_speaker_types.h"
 #include "DNA_texture_types.h"
@@ -583,9 +582,6 @@ void DepsgraphRelationBuilder::build_id(ID *id)
     case ID_SCE:
       build_scene_parameters((Scene *)id);
       break;
-    case ID_SIM:
-      build_simulation((Simulation *)id);
-      break;
     case ID_PA:
       build_particle_settings((ParticleSettings *)id);
       break;
@@ -3147,31 +3143,6 @@ void DepsgraphRelationBuilder::build_sound(bSound *sound)
   add_relation(parameters_key, audio_key, "Parameters -> Audio");
 }
 
-void DepsgraphRelationBuilder::build_simulation(Simulation *simulation)
-{
-  if (built_map_.checkIsBuiltAndTag(simulation)) {
-    return;
-  }
-
-  const BuilderStack::ScopedEntry stack_entry = stack_.trace(simulation->id);
-
-  build_idproperties(simulation->id.properties);
-  build_animdata(&simulation->id);
-  build_parameters(&simulation->id);
-
-  build_nodetree(simulation->nodetree);
-  build_nested_nodetree(&simulation->id, simulation->nodetree);
-
-  OperationKey simulation_eval_key(
-      &simulation->id, NodeType::SIMULATION, OperationCode::SIMULATION_EVAL);
-  TimeSourceKey time_src_key;
-  add_relation(time_src_key, simulation_eval_key, "TimeSrc -> Simulation");
-
-  OperationKey nodetree_key(
-      &simulation->nodetree->id, NodeType::PARAMETERS, OperationCode::PARAMETERS_EXIT);
-  add_relation(nodetree_key, simulation_eval_key, "NodeTree -> Simulation", 0);
-}
-
 using Seq_build_prop_cb_data = struct Seq_build_prop_cb_data {
   DepsgraphRelationBuilder *builder;
   ComponentKey sequencer_key;
diff --git a/source/blender/depsgraph/intern/builder/deg_builder_relations.h b/source/blender/depsgraph/intern/builder/deg_builder_relations.h
index 861cc2fbe28..513ce4d988f 100644
--- a/source/blender/depsgraph/intern/builder/deg_builder_relations.h
+++ b/source/blender/depsgraph/intern/builder/deg_builder_relations.h
@@ -54,7 +54,6 @@ struct Object;
 struct ParticleSettings;
 struct ParticleSystem;
 struct Scene;
-struct Simulation;
 struct Speaker;
 struct Tex;
 struct VFont;
@@ -232,7 +231,6 @@ class DepsgraphRelationBuilder : public DepsgraphBuilder {
   virtual void build_lightprobe(LightProbe *probe);
   virtual void build_speaker(Speaker *speaker);
   virtual void build_sound(bSound *sound);
-  virtual void build_simulation(Simulation *simulation);
   virtual void build_scene_sequencer(Scene *scene);
   virtual void build_scene_audio(Scene *scene);
   virtual void build_scene_speakers(Scene *scene, ViewLayer *view_layer);
diff --git a/source/blender/depsgraph/intern/debug/deg_debug_relations_graphviz.cc b/source/blender/depsgraph/intern/debug/deg_debug_relations_graphviz.cc
index 2c594f578f9..9da2c3c4080 100644
--- a/source/blender/depsgraph/intern/debug/deg_debug_relations_graphviz.cc
+++ b/source/blender/depsgraph/intern/debug/deg_debug_relations_graphviz.cc
@@ -410,8 +410,7 @@ static void deg_debug_graphviz_node(DotExportContext &ctx,
     case NodeType::GENERIC_DATABLOCK:
     case NodeType::VISIBILITY:
     case NodeType::NTREE_OUTPUT:
-    case NodeType::NTREE_GEOMETRY_PREPROCESS:
-    case NodeType::SIMULATION: {
+    case NodeType::NTREE_GEOMETRY_PREPROCESS: {
       ComponentNode *comp_node = (ComponentNode *)node;
       if (comp_node->operations.is_empty()) {
         deg_debug_graphviz_node_single(ctx, node, parent_cluster);
diff --git a/source/blender/depsgraph/intern/depsgraph_build.cc b/source/blender/depsgraph/intern/depsgraph_build.cc
index 76481c870d8..6c07fc4c294 100644
--- a/source/blender/depsgraph/intern/depsgraph_build.cc
+++ b/source/blender/depsgraph/intern/depsgraph_build.cc
@@ -21,7 +21,6 @@
 #include "DNA_node_types.h"
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"
-#include "DNA_simulation_types.h"
 
 #include "BKE_collection.h"
 #include "BKE_main.h"
@@ -123,16 +122,6 @@ void DEG_add_collection_geometry_customdata_mask(DepsNodeHandle *node_handle,
   FOREACH_COLLECTION_OBJECT_RECURSIVE_END;
 }
 
-void DEG_add_simulation_relation(DepsNodeHandle *node_handle,
-                                 Simulation *simulation,
-                                 const char *description)
-{
-  deg::OperationKey operation_key(
-      &simulation->id, deg::NodeType::SIMULATION, deg::OperationCode::SIMULATION_EVAL);
-  deg::DepsNodeHandle *deg_node_handle = get_node_handle(node_handle);
-  deg_node_handle->builder->add_node_handle_relation(operation_key, deg_node_handle, description);
-}
-
 void DEG_add_node_tree_output_relation(DepsNodeHandle *node_handle,
                                        bNodeTree *node_tree,
                                        const char *description)
diff --git a/source/blender/depsgraph/intern/depsgraph_tag.cc b/source/blender/depsgraph/intern/depsgraph_tag.cc
index 943766132ae..3afa06b8a20 100644
--- a/source/blender/depsgraph/intern/depsgraph_tag.cc
+++ b/source/blender/depsgraph/intern/depsgraph_tag.cc
@@ -819,7 +819,6 @@ void DEG_graph_id_type_tag(Depsgraph *depsgraph, short id_type)
     DEG_graph_id_type_tag(depsgraph, ID_LA);
     DEG_graph_id_type_tag(depsgraph, ID_WO);
     DEG_graph_id_type_tag(depsgraph, ID_SCE);
-    DEG_graph_id_type_tag(depsgraph, ID_SIM);
   }
   const int id_type_index = BKE_idtype_idcode_to_index(id_type);
   deg::Depsgraph *deg_graph = reinterpret_cast<deg::Depsgraph *>(depsgraph);
diff --git a/source/blender/depsgraph/intern/eval/deg_eval_copy_on_write.cc b/source/blender/depsgraph/intern/eval/deg_eval_copy_on_write.cc
index 73ecf3f7bc6..adf5bb627a8 100644
--- a/source/blender/depsgraph/intern/eval/deg_eval_copy_on_write.cc
+++ b/source/blender/depsgraph/intern/eval/deg_eval_copy_on_write.cc
@@ -50,7 +50,6 @@
 #include "DNA_rigidbody_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_sound_types.h"
 
 #include "DRW_engine.h"
@@ -107,7 +106,6 @@ union NestedIDHackTempStorage {
   Scene scene;
   Tex tex;
   World world;
-  Simulation simulation;
 };
 
 /* Set nested owned ID pointers to nullptr. */
@@ -125,7 +123,6 @@ void nested_id_hack_discard_pointers(ID *id_cow)
     SPECIAL_CASE(ID_MA, Material, nodetree)
     SPECIAL_CASE(ID_TE, Tex, nodetree)
     SPECIAL_CASE(ID_WO, World, nodetree)
-    SPECIAL_CASE(ID_SIM, Simulation, nodetree)
 
     SPECIAL_CASE(ID_CU_LEGACY, Curve, key)
     SPECIAL_CASE(ID_LT, Lattice, key)
@@ -174,7 +171,6 @@ const ID *nested_id_hack_get_discarded_pointers(NestedIDHackTempStorage *storage
     SPECIAL_CASE(ID_MA, Material, nodetree, material)
     SPECIAL_CASE(ID_TE, Tex, nodetree, tex)
     SPECIAL_CASE(ID_WO, World, nodetree, world)
-    SPECIAL_CASE(ID_SIM, Simulation, nodetree, simulation)
 
     SPECIAL_CASE(ID_CU_LEGACY, Curve, key, curve)
     SPECIAL_CASE(ID_LT, Lattice, key, lattice)
@@ -214,7 +210,6 @@ void nested_id_hack_restore_pointers(const ID *old_id, ID *new_id)
     SPECIAL_CASE(ID_SCE, Scene, nodetree)
     SPECIAL_CASE(ID_TE, Tex, nodetree)
     SPECIAL_CASE(ID_WO, World, nodetree)
-    SPECIAL_CASE(ID_SIM, Simulation, nodetree)
 
     SPECIAL_CASE(ID_CU_LEGACY, Curve, key)
     SPECIAL_CASE(ID_LT, Lattice, key)
@@ -252,7 +247,6 @@ void ntree_hack_remap_pointers(const Depsgraph *depsgraph, ID *id_cow)
     SPECIAL_CASE(ID_SCE, Scene, nodetree, bNodeTree)
     SPECIAL_CASE(ID_TE, Tex, nodetree, bNodeTree)
     SPECIAL_CASE(ID_WO, World, nodetree, bNodeTree)
-    SPECIAL_CASE(ID_SIM, Simulation, nodetree, bNodeTree)
 
     SPECIAL_CASE(ID_CU_LEGACY, Curve, key, Key)
     SPECIAL_CASE(ID_LT, Lattice, key, Key)
diff --git a/source/blender/depsgraph/intern/node/deg_node.cc b/source/blender/depsgraph/intern/node/deg_node.cc
index 29c6b7ee725..0a844d574c1 100644
--- a/source/blender/depsgraph/intern/node/deg_node.cc
+++ b/source/blender/depsgraph/intern/node/deg_node.cc
@@ -99,8 +99,6 @@ const char *nodeTypeAsString(NodeType type)
       return "GENERIC_DATABLOCK";
     case NodeType::VISIBILITY:
       return "VISIBILITY";
-    case NodeType::SIMULATION:
-      return "SIMULATION";
     case NodeType::NTREE_OUTPUT:
       return "NTREE_OUTPUT";
     case NodeType::NTREE_GEOMETRY_PREPROCESS:
@@ -162,7 +160,6 @@ eDepsSceneComponentType nodeTypeToSceneComponent(NodeType type)
     case NodeType::BONE:
     case NodeType::SHADING:
     case NodeType::CACHE:
-    case NodeType::SIMULATION:
     case NodeType::NTREE_OUTPUT:
     case NodeType::NTREE_GEOMETRY_PREPROCESS:
       return DEG_SCENE_COMP_PARAMETERS;
@@ -238,7 +235,6 @@ eDepsObjectComponentType nodeTypeToObjectComponent(NodeType type)
     case NodeType::BATCH_CACHE:
     case NodeType::DUPLI:
     case NodeType::SYNCHRONIZATION:
-    case NodeType::SIMULATION:
     case NodeType::NTREE_OUTPUT:
     case NodeType::NTREE_GEOMETRY_PREPROCESS:
     case NodeType::UNDEFINED:
diff --git a/source/blender/depsgraph/intern/node/deg_node.h b/source/blender/depsgraph/intern/node/deg_node.h
index c2180e99d06..eb5f27e4795 100644
--- a/source/blender/depsgraph/intern/node/deg_node.h
+++ b/source/blender/depsgraph/intern/node/deg_node.h
@@ -129,8 +129,6 @@ enum class NodeType {
   DUPLI,
   /* Synchronization back to original datablock. */
   SYNCHRONIZATION,
-  /* Simulation component. */
-  SIMULATION,
   /* Node tree output component. */
   NTREE_OUTPUT,
   /* Preprocessing for geometry node trees before they can be evaluated. */
diff --git a/source/blender/depsgraph/intern/node/deg_node_component.cc b/source/blender/depsgraph/intern/node/deg_node_component.cc
index 31d57a877bc..1b4df9decbe 100644
--- a/source/blender/depsgraph/intern/node/deg_node_component.cc
+++ b/source/blender/depsgraph/intern/node/deg_node_component.cc
@@ -339,7 +339,6 @@ DEG_COMPONENT_NODE_DEFINE(Audio, AUDIO, 0);
 DEG_COMPONENT_NODE_DEFINE(Armature, ARMATURE, 0);
 DEG_COMPONENT_NODE_DEFINE(GenericDatablock, GENERIC_DATABLOCK, 0);
 DEG_COMPONENT_NODE_DEFINE(Visibility, VISIBILITY, 0);
-DEG_COMPONENT_NODE_DEFINE(Simulation, SIMULATION, 0);
 DEG_COMPONENT_NODE_DEFINE(NTreeOutput, NTREE_OUTPUT, ID_RECALC_NTREE_OUTPUT);
 DEG_COMPONENT_NODE_DEFINE(NTreeGeometryPreprocess, NTREE_GEOMETRY_PREPROCESS, 0);
 
@@ -375,7 +374,6 @@ void deg_register_component_depsnodes()
   register_node_typeinfo(&DNTI_ARMATURE);
   register_node_typeinfo(&DNTI_GENERIC_DATABLOCK);
   register_node_typeinfo(&DNTI_VISIBILITY);
-  register_node_typeinfo(&DNTI_SIMULATION);
   register_node_typeinfo(&DNTI_NTREE_OUTPUT);
   register_node_typeinfo(&DNTI_NTREE_GEOMETRY_PREPROCESS);
 }
diff --git a/source/blender/depsgraph/intern/node/deg_node_operation.cc b/source/blender/depsgraph/intern/node/deg_node_operation.cc
index 590999b9593..f03c8b08eb6 100644
--- a/source/blender/depsgraph/intern/node/deg_node_operation.cc
+++ b/source/blender/depsgraph/intern/node/deg_node_operation.cc
@@ -200,8 +200,6 @@ const char *operationCodeAsString(OperationCode opcode)
     /* instancing/duplication. */
     case OperationCode::DUPLI:
       return "DUPLI";
-    case OperationCode::SIMULATION_EVAL:
-      return "SIMULATION_EVAL";
   }
   BLI_assert_msg(0, "Unhandled operation code, should never happen.");
   return "UNKNOWN";
diff --git a/source/blender/depsgraph/intern/node/deg_node_operation.h b/source/blender/depsgraph/intern/node/deg_node_operation.h
index 60681037b95..e243fc4353c 100644
--- a/source/blender/depsgraph/intern/node/deg_node_operation.h
+++ b/source/blender/depsgraph/intern/node/deg_node_operation.h
@@ -199,9 +199,6 @@ enum class OperationCode {
 
   /* Duplication/instancing system. --------------------------------------- */
   DUPLI,
-
-  /* Simulation. ---------------------------------------------------------- */
-  SIMULATION_EVAL,
 };
 const char *operationCodeAsString(OperationCode opcode);
 
diff --git a/source/blender/editors/animation/anim_channels_defines.cc b/source/blender/editors/animation/anim_channels_defines.cc
index d7ec7a8f5e5..e68a96b8ddf 100644
--- a/source/blender/editors/animation/anim_channels_defines.cc
+++ b/source/blender/editors/animation/anim_channels_defines.cc
@@ -36,7 +36,6 @@
 #include "DNA_pointcloud_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_screen_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_space_types.h"
 #include "DNA_speaker_types.h"
 #include "DNA_userdef_types.h"
@@ -3043,84 +3042,6 @@ static bAnimChannelType ACF_DSVOLUME = {
     /*setting_flag*/ acf_dsvolume_setting_flag,
     /*setting_ptr*/ acf_dsvolume_setting_ptr};
 
-/* Simulation Expander ----------------------------------------- */
-
-static int acf_dssimulation_icon(bAnimListElem * /*ale*/)
-{
-  /* TODO: Use correct icon. */
-  return ICON_PHYSICS;
-}
-
-static int acf_dssimulation_setting_flag(bAnimContext * /*ac*/,
-                                         eAnimChannel_Settings setting,
-                                         bool *r_neg)
-{
-  /* Clear extra return data first. */
-  *r_neg = false;
-
-  switch (setting) {
-    case ACHANNEL_SETTING_EXPAND: /* expanded */
-      return SIM_DS_EXPAND;
-
-    case ACHANNEL_SETTING_MUTE: /* mute (only in NLA) */
-      return ADT_NLA_EVAL_OFF;
-
-    case ACHANNEL_SETTING_VISIBLE: /* visible (only in Graph Editor) */
-      *r_neg = true;
-      return ADT_CURVES_NOT_VISIBLE;
-
-    case ACHANNEL_SETTING_SELECT: /* selected */
-      return ADT_UI_SELECTED;
-
-    default: /* unsupported */
-      return 0;
-  }
-}
-
-static void *acf_dssimulation_setting_ptr(bAnimListElem *ale,
-                                          eAnimChannel_Settings setting,
-                                          short *r_type)
-{
-  Simulation *simulation = (Simulation *)ale->data;
-
-  /* Clear extra return data first. */
-  *r_type = 0;
-
-  switch (setting) {
-    case ACHANNEL_SETTING_EXPAND: /* expanded */
-      return GET_ACF_FLAG_PTR(simulation->flag, r_type);
-
-    case ACHANNEL_SETTING_SELECT:  /* selected */
-    case ACHANNEL_SETTING_MUTE:    /* muted (for NLA only) */
-    case ACHANNEL_SETTING_VISIBLE: /* visible (for Graph Editor only) */
-      if (simulation->adt) {
-        return GET_ACF_FLAG_PTR(simulation->adt->flag, r_type);
-      }
-      return nullptr;
-
-    default: /* unsupported */
-      return nullptr;
-  }
-}
-
-/** Simulation expander type define. */
-static bAnimChannelType ACF_DSSIMULATION = {
-    /*channel_type_name*/ "Simulation Expander",
-    /*channel_role*/ ACHANNEL_ROLE_EXPANDER,
-
-    /*get_backdrop_color*/ acf_generic_dataexpand_color,
-    /*draw_backdrop*/ acf_generic_dataexpand_backdrop,
-    /*get_indent_level*/ acf_generic_indentation_1,
-    /*get_offset*/ acf_generic_basic_offset,
-
-    /*name*/ acf_generic_idblock_name,
-    /*name_prop*/ acf_generic_idblock_name_prop,
-    /*icon*/ acf_dssimulation_icon,
-
-    /*has_setting*/ acf_generic_dataexpand_setting_valid,
-    /*setting_flag*/ acf_dssimulation_setting_flag,
-    /*setting_ptr*/ acf_dssimulation_setting_ptr};
-
 /* GPencil Expander  ------------------------------------------- */
 
 /* TODO: just get this from RNA? */
@@ -4132,7 +4053,6 @@ static void ANIM_init_channel_typeinfo_data()
     animchannelTypeInfo[type++] = &ACF_DSCURVES;     /* Curves Channel */
     animchannelTypeInfo[type++] = &ACF_DSPOINTCLOUD; /* PointCloud Channel */
     animchannelTypeInfo[type++] = &ACF_DSVOLUME;     /* Volume Channel */
-    animchannelTypeInfo[type++] = &ACF_DSSIMULATION; /* Simulation Channel */
 
     animchannelTypeInfo[type++] = &ACF_SHAPEKEY; /* ShapeKey */
 
diff --git a/source/blender/editors/animation/anim_filter.cc b/source/blender/editors/animation/anim_filter.cc
index 09004341c1e..f6730dcbbf9 100644
--- a/source/blender/editors/animation/anim_filter.cc
+++ b/source/blender/editors/animation/anim_filter.cc
@@ -52,7 +52,6 @@
 #include "DNA_scene_types.h"
 #include "DNA_screen_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_space_types.h"
 #include "DNA_speaker_types.h"
 #include "DNA_userdef_types.h"
@@ -797,18 +796,6 @@ static bAnimListElem *make_new_animlistelem(void *data,
         ale->adt = BKE_animdata_from_id(static_cast<ID *>(data));
         break;
       }
-      case ANIMTYPE_DSSIMULATION: {
-        Simulation *simulation = (Simulation *)data;
-        AnimData *adt = simulation->adt;
-
-        ale->flag = FILTER_SIMULATION_OBJD(simulation);
-
-        ale->key_data = (adt) ? adt->action : nullptr;
-        ale->datatype = ALE_ACT;
-
-        ale->adt = BKE_animdata_from_id(static_cast<ID *>(data));
-        break;
-      }
       case ANIMTYPE_DSSKEY: {
         Key *key = (Key *)data;
         AnimData *adt = key->adt;
diff --git a/source/blender/editors/include/ED_anim_api.h b/source/blender/editors/include/ED_anim_api.h
index 005f17c7096..3f1135bd162 100644
--- a/source/blender/editors/include/ED_anim_api.h
+++ b/source/blender/editors/include/ED_anim_api.h
@@ -372,8 +372,6 @@ ENUM_OPERATORS(eAnimFilter_Flags, ANIMFILTER_TMP_IGNORE_ONLYSEL);
 #define FILTER_CURVES_OBJD(ha) (CHECK_TYPE_INLINE(ha, Curves *), ((ha->flag & HA_DS_EXPAND)))
 #define FILTER_POINTS_OBJD(pt) (CHECK_TYPE_INLINE(pt, PointCloud *), ((pt->flag & PT_DS_EXPAND)))
 #define FILTER_VOLUME_OBJD(vo) (CHECK_TYPE_INLINE(vo, Volume *), ((vo->flag & VO_DS_EXPAND)))
-#define FILTER_SIMULATION_OBJD(sim) \
-  (CHECK_TYPE_INLINE(sim, Simulation *), ((sim->flag & SIM_DS_EXPAND)))
 /* Variable use expanders */
 #define FILTER_NTREE_DATA(ntree) \
   (CHECK_TYPE_INLINE(ntree, bNodeTree *), (((ntree)->flag & NTREE_DS_EXPAND)))
diff --git a/source/blender/editors/interface/interface_icons.cc b/source/blender/editors/interface/interface_icons.cc
index c68241fc578..90c05adb420 100644
--- a/source/blender/editors/interface/interface_icons.cc
+++ b/source/blender/editors/interface/interface_icons.cc
@@ -2457,9 +2457,6 @@ int UI_icon_from_idcode(const int idcode)
       return ICON_WORLD_DATA;
     case ID_WS:
       return ICON_WORKSPACE;
-    case ID_SIM:
-      /* TODO: Use correct icon. */
-      return ICON_PHYSICS;
     case ID_GP:
       return ICON_OUTLINER_DATA_GREASEPENCIL;
 
diff --git a/source/blender/editors/interface/interface_templates.cc b/source/blender/editors/interface/interface_templates.cc
index fdd7a3897a9..bbfb337e630 100644
--- a/source/blender/editors/interface/interface_templates.cc
+++ b/source/blender/editors/interface/interface_templates.cc
@@ -1136,8 +1136,6 @@ static const char *template_id_browse_tip(const StructRNA *type)
         return N_("Browse Point Cloud Data to be linked");
       case ID_VO:
         return N_("Browse Volume Data to be linked");
-      case ID_SIM:
-        return N_("Browse Simulation to be linked");
       case ID_GP:
         return N_("Browse Grease Pencil Data to be linked");
 
@@ -1236,8 +1234,7 @@ static uiBut *template_id_def_new_but(uiBlock *block,
                             BLT_I18NCONTEXT_ID_LIGHTPROBE,
                             BLT_I18NCONTEXT_ID_CURVES,
                             BLT_I18NCONTEXT_ID_POINTCLOUD,
-                            BLT_I18NCONTEXT_ID_VOLUME,
-                            BLT_I18NCONTEXT_ID_SIMULATION, );
+                            BLT_I18NCONTEXT_ID_VOLUME, );
   BLT_I18N_MSGID_MULTI_CTXT("New", BLT_I18NCONTEXT_ID_PAINTCURVE, );
   /* NOTE: BLT_I18N_MSGID_MULTI_CTXT takes a maximum number of parameters,
    * check the definition to see if a new call must be added when the limit
diff --git a/source/blender/editors/render/render_opengl.cc b/source/blender/editors/render/render_opengl.cc
index a7b8f278556..9607065fdf3 100644
--- a/source/blender/editors/render/render_opengl.cc
+++ b/source/blender/editors/render/render_opengl.cc
@@ -602,7 +602,6 @@ static int gather_frames_to_render_for_id(LibraryIDLinkCallbackData *cb_data)
     case ID_CV:        /* Curves */
     case ID_PT:        /* PointCloud */
     case ID_VO:        /* Volume */
-    case ID_SIM:       /* Simulation */
       break;
 
       /* Blacklist: */
diff --git a/source/blender/editors/space_outliner/outliner_draw.cc b/source/blender/editors/space_outliner/outliner_draw.cc
index ce9651118a5..7f1a34bebe1 100644
--- a/source/blender/editors/space_outliner/outliner_draw.cc
+++ b/source/blender/editors/space_outliner/outliner_draw.cc
@@ -2499,9 +2499,6 @@ static BIFIconID tree_element_get_icon_from_id(const ID *id)
       return ICON_SEQUENCE;
     case ID_PC:
       return ICON_CURVE_BEZCURVE;
-    case ID_SIM:
-      /* TODO: Use correct icon. */
-      return ICON_PHYSICS;
     default:
       return ICON_NONE;
   }
diff --git a/source/blender/editors/space_outliner/outliner_intern.hh b/source/blender/editors/space_outliner/outliner_intern.hh
index 5ab885e524d..ab9629603bb 100644
--- a/source/blender/editors/space_outliner/outliner_intern.hh
+++ b/source/blender/editors/space_outliner/outliner_intern.hh
@@ -135,7 +135,6 @@ struct TreeElementIcon {
         ID_CV, \
         ID_PT, \
         ID_VO, \
-        ID_SIM, \
         ID_GP) || /* Only in 'blendfile' mode ... :/ */ \
    ELEM(GS((_id)->name), \
         ID_SCR, \
diff --git a/source/blender/editors/space_outliner/outliner_tools.cc b/source/blender/editors/space_outliner/outliner_tools.cc
index ce770eed397..d4226382fb6 100644
--- a/source/blender/editors/space_outliner/outliner_tools.cc
+++ b/source/blender/editors/space_outliner/outliner_tools.cc
@@ -26,7 +26,6 @@
 #include "DNA_pointcloud_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_volume_types.h"
 #include "DNA_world_types.h"
 
@@ -165,7 +164,6 @@ static void get_element_operation_type(
       case ID_CV:
       case ID_PT:
       case ID_VO:
-      case ID_SIM:
       case ID_GP:
         is_standard_id = true;
         break;
diff --git a/source/blender/editors/space_outliner/tree/tree_element_id.cc b/source/blender/editors/space_outliner/tree/tree_element_id.cc
index 64a7e59ac70..577f37dcd2e 100644
--- a/source/blender/editors/space_outliner/tree/tree_element_id.cc
+++ b/source/blender/editors/space_outliner/tree/tree_element_id.cc
@@ -85,7 +85,6 @@ std::unique_ptr<TreeElementID> TreeElementID::createFromID(TreeElement &legacy_t
     case ID_CV:
     case ID_PT:
     case ID_VO:
-    case ID_SIM:
     case ID_WM:
     case ID_IM:
     case ID_VF:
diff --git a/source/blender/makesdna/DNA_ID.h b/source/blender/makesdna/DNA_ID.h
index dda24c1aa56..2ed7307389d 100644
--- a/source/blender/makesdna/DNA_ID.h
+++ b/source/blender/makesdna/DNA_ID.h
@@ -1253,7 +1253,6 @@ typedef enum eID_Index {
 
   /* Simulation-related types. */
   INDEX_ID_CF,
-  INDEX_ID_SIM,
   INDEX_ID_PA,
 
   /* Shape Keys snow-flake, can be used by several obdata types. */
diff --git a/source/blender/makesdna/DNA_ID_enums.h b/source/blender/makesdna/DNA_ID_enums.h
index d43e9cab6e9..4f6e3d5fb3c 100644
--- a/source/blender/makesdna/DNA_ID_enums.h
+++ b/source/blender/makesdna/DNA_ID_enums.h
@@ -83,7 +83,6 @@ typedef enum ID_Type {
   ID_CV = MAKE_ID2('C', 'V'),        /* Curves */
   ID_PT = MAKE_ID2('P', 'T'),        /* PointCloud */
   ID_VO = MAKE_ID2('V', 'O'),        /* Volume */
-  ID_SIM = MAKE_ID2('S', 'I'),       /* Simulation (geometry node groups) */
   ID_GP = MAKE_ID2('G', 'P'),        /* Grease Pencil */
 } ID_Type;
 
diff --git a/source/blender/makesdna/DNA_simulation_types.h b/source/blender/makesdna/DNA_simulation_types.h
deleted file mode 100644
index 8ccb9ff4948..00000000000
--- a/source/blender/makesdna/DNA_simulation_types.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/* SPDX-FileCopyrightText: 2023 Blender Foundation
- *
- * SPDX-License-Identifier: GPL-2.0-or-later */
-
-/** \file
- * \ingroup DNA
- */
-
-#pragma once
-
-#include "DNA_ID.h"
-#include "DNA_customdata_types.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-typedef struct Simulation {
-  DNA_DEFINE_CXX_METHODS(Simulation)
-
-  ID id;
-  struct AnimData *adt; /* animation data (must be immediately after id) */
-
-  /* This nodetree is embedded into the data block. */
-  struct bNodeTree *nodetree;
-
-  uint32_t flag;
-  char _pad[4];
-} Simulation;
-
-/** #Simulation.flag */
-enum {
-  SIM_DS_EXPAND = (1 << 0),
-};
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/source/blender/makesdna/intern/dna_defaults.c b/source/blender/makesdna/intern/dna_defaults.c
index d76b30e9506..d29e4973b94 100644
--- a/source/blender/makesdna/intern/dna_defaults.c
+++ b/source/blender/makesdna/intern/dna_defaults.c
@@ -99,7 +99,6 @@
 #include "DNA_particle_types.h"
 #include "DNA_pointcloud_types.h"
 #include "DNA_scene_types.h"
-#include "DNA_simulation_types.h"
 #include "DNA_space_types.h"
 #include "DNA_speaker_types.h"
 #include "DNA_texture_types.h"
@@ -130,7 +129,6 @@
 #include "DNA_particle_defaults.h"
 #include "DNA_pointcloud_defaults.h"
 #include "DNA_scene_defaults.h"
-#include "DNA_simulation_defaults.h"
 #include "DNA_space_defaults.h"
 #include "DNA_speaker_defaults.h"
 #include "DNA_texture_defaults.h"
@@ -213,9 +211,6 @@ SDNA_DEFAULT_DECL_STRUCT(PointCloud);
 SDNA_DEFAULT_DECL_STRUCT(Scene);
 SDNA_DEFAULT_DECL_STRUCT(ToolSettings);
 
-/* DNA_simulation_defaults.h */
-SDNA_DEFAULT_DECL_STRUCT(Simulation);
-
 /* DNA_space_defaults.h */
 SDNA_DEFAULT_DECL_STRUCT(SpaceClip);
 
@@ -451,9 +446,6 @@ const void *DNA_default_table[SDNA_TYPE_MAX] = {
     SDNA_DEFAULT_DECL_EX(GP_Sculpt_Settings, ToolSettings.gp_sculpt),
     SDNA_DEFAULT_DECL_EX(GP_Sculpt_Guide, ToolSettings.gp_sculpt.guide),
 
-    /* DNA_simulation_defaults.h */
-    SDNA_DEFAULT_DECL(Simulation),
-
     /* DNA_speaker_defaults.h */
     SDNA_DEFAULT_DECL(Speaker),
 
diff --git a/source/blender/makesrna/intern/CMakeLists.txt b/source/blender/makesrna/intern/CMakeLists.txt
index 108c9289eef..5e0d2c20789 100644
--- a/source/blender/makesrna/intern/CMakeLists.txt
+++ b/source/blender/makesrna/intern/CMakeLists.txt
@@ -94,7 +94,6 @@ if(WITH_EXPERIMENTAL_FEATURES)
   add_definitions(-DWITH_GREASE_PENCIL_V3)
   list(APPEND DEFSRC
     rna_grease_pencil.cc
-    rna_simulation.cc
   )
 endif()
 
diff --git a/source/blender/makesrna/intern/makesrna.c b/source/blender/makesrna/intern/makesrna.c
index 8e39a4d2b45..fb693734421 100644
--- a/source/blender/makesrna/intern/makesrna.c
+++ b/source/blender/makesrna/intern/makesrna.c
@@ -4622,9 +4622,6 @@ static RNAProcessItem PROCESS_ITEMS[] = {
     {"rna_screen.cc", NULL, RNA_def_screen},
     {"rna_sculpt_paint.cc", NULL, RNA_def_sculpt_paint},
     {"rna_sequencer.cc", "rna_sequencer_api.cc", RNA_def_sequencer},
-#ifdef WITH_SIMULATION_DATABLOCK
-    {"rna_simulation.cc", NULL, RNA_def_simulation},
-#endif
     {"rna_space.cc", "rna_space_api.cc", RNA_def_space},
     {"rna_speaker.cc", NULL, RNA_def_speaker},
     {"rna_test.c", NULL, RNA_def_test},
diff --git a/source/blender/makesrna/intern/rna_ID.c b/source/blender/makesrna/intern/rna_ID.c
index 3376ff15e58..240868bff2f 100644
--- a/source/blender/makesrna/intern/rna_ID.c
+++ b/source/blender/makesrna/intern/rna_ID.c
@@ -63,7 +63,6 @@ const EnumPropertyItem rna_enum_id_type_items[] = {
     {ID_PA, "PARTICLE", ICON_PARTICLE_DATA, "Particle", ""},
     {ID_PT, "POINTCLOUD", ICON_POINTCLOUD_DATA, "Point Cloud", ""},
     {ID_SCE, "SCENE", ICON_SCENE_DATA, "Scene", ""},
-    {ID_SIM, "SIMULATION", ICON_PHYSICS, "Simulation", ""}, /* TODO: Use correct icon. */
     {ID_SO, "SOUND", ICON_SOUND, "Sound", ""},
     {ID_SPK, "SPEAKER", ICON_SPEAKER, "Speaker", ""},
     {ID_TXT, "TEXT", ICON_TEXT, "Text", ""},
@@ -191,11 +190,6 @@ const struct IDFilterEnumPropertyItem rna_enum_id_type_filter_items[] = {
      "Point Clouds",
      "Show/hide Point Cloud data-blocks"},
     {FILTER_ID_SCE, "filter_scene", ICON_SCENE_DATA, "Scenes", "Show Scene data-blocks"},
-    {FILTER_ID_SIM,
-     "filter_simulation",
-     ICON_PHYSICS,
-     "Simulations",
-     "Show Simulation data-blocks"}, /* TODO: Use correct icon. */
     {FILTER_ID_SPK, "filter_speaker", ICON_SPEAKER, "Speakers", "Show Speaker data-blocks"},
     {FILTER_ID_SO, "filter_sound", ICON_SOUND, "Sounds", "Show Sound data-blocks"},
     {FILTER_ID_TE, "filter_texture", ICON_TEXTURE_DATA, "Textures", "Show Texture data-blocks"},
@@ -432,11 +426,6 @@ short RNA_type_to_ID_code(const StructRNA *type)
   if (base_type == &RNA_Screen) {
     return ID_SCR;
   }
-#  ifdef WITH_SIMULATION_DATABLOCK
-  if (base_type == &RNA_Simulation) {
-    return ID_SIM;
-  }
-#  endif
   if (base_type == &RNA_Sound) {
     return ID_SO;
   }
@@ -534,12 +523,6 @@ StructRNA *ID_code_to_RNA_type(short idcode)
       return &RNA_Scene;
     case ID_SCR:
       return &RNA_Screen;
-    case ID_SIM:
-#  ifdef WITH_SIMULATION_DATABLOCK
-      return &RNA_Simulation;
-#  else
-      return &RNA_ID;
-#  endif
     case ID_SO:
       return &RNA_Sound;
     case ID_SPK:
diff --git a/source/blender/makesrna/intern/rna_ID.cc b/source/blender/makesrna/intern/rna_ID.cc
index 87598c717b8..e448e815d42 100644
--- a/source/blender/makesrna/intern/rna_ID.cc
+++ b/source/blender/makesrna/intern/rna_ID.cc
@@ -63,7 +63,6 @@ const EnumPropertyItem rna_enum_id_type_items[] = {
     {ID_PA, "PARTICLE", ICON_PARTICLE_DATA, "Particle", ""},
     {ID_PT, "POINTCLOUD", ICON_POINTCLOUD_DATA, "Point Cloud", ""},
     {ID_SCE, "SCENE", ICON_SCENE_DATA, "Scene", ""},
-    {ID_SIM, "SIMULATION", ICON_PHYSICS, "Simulation", ""}, /* TODO: Use correct icon. */
     {ID_SO, "SOUND", ICON_SOUND, "Sound", ""},
     {ID_SPK, "SPEAKER", ICON_SPEAKER, "Speaker", ""},
     {ID_TXT, "TEXT", ICON_TEXT, "Text", ""},
@@ -191,11 +190,6 @@ const IDFilterEnumPropertyItem rna_enum_id_type_filter_items[] = {
      "Point Clouds",
      "Show/hide Point Cloud data-blocks"},
     {FILTER_ID_SCE, "filter_scene", ICON_SCENE_DATA, "Scenes", "Show Scene data-blocks"},
-    {FILTER_ID_SIM,
-     "filter_simulation",
-     ICON_PHYSICS,
-     "Simulations",
-     "Show Simulation data-blocks"}, /* TODO: Use correct icon. */
     {FILTER_ID_SPK, "filter_speaker", ICON_SPEAKER, "Speakers", "Show Speaker data-blocks"},
     {FILTER_ID_SO, "filter_sound", ICON_SOUND, "Sounds", "Show Sound data-blocks"},
     {FILTER_ID_TE, "filter_texture", ICON_TEXTURE_DATA, "Textures", "Show Texture data-blocks"},
@@ -432,11 +426,6 @@ short RNA_type_to_ID_code(const StructRNA *type)
   if (base_type == &RNA_Screen) {
     return ID_SCR;
   }
-#  ifdef WITH_SIMULATION_DATABLOCK
-  if (base_type == &RNA_Simulation) {
-    return ID_SIM;
-  }
-#  endif
   if (base_type == &RNA_Sound) {
     return ID_SO;
   }
@@ -534,12 +523,6 @@ StructRNA *ID_code_to_RNA_type(short idcode)
       return &RNA_Scene;
     case ID_SCR:
       return &RNA_Screen;
-    case ID_SIM:
-#  ifdef WITH_SIMULATION_DATABLOCK
-      return &RNA_Simulation;
-#  else
-      return &RNA_ID;
-#  endif
     case ID_SO:
       return &RNA_Sound;
     case ID_SPK:
diff --git a/source/blender/makesrna/intern/rna_internal.h b/source/blender/makesrna/intern/rna_internal.h
index 119a0256ebc..22d84d3c509 100644
--- a/source/blender/makesrna/intern/rna_internal.h
+++ b/source/blender/makesrna/intern/rna_internal.h
@@ -516,9 +516,6 @@ void RNA_def_main_lightprobes(BlenderRNA *brna, PropertyRNA *cprop);
 void RNA_def_main_hair_curves(BlenderRNA *brna, PropertyRNA *cprop);
 void RNA_def_main_pointclouds(BlenderRNA *brna, PropertyRNA *cprop);
 void RNA_def_main_volumes(BlenderRNA *brna, PropertyRNA *cprop);
-#ifdef WITH_SIMULATION_DATABLOCK
-void RNA_def_main_simulations(BlenderRNA *brna, PropertyRNA *cprop);
-#endif
 
 /* ID Properties */
 
diff --git a/source/blender/makesrna/intern/rna_main.cc b/source/blender/makesrna/intern/rna_main.cc
index 2ae91d2d039..72081bad9d5 100644
--- a/source/blender/makesrna/intern/rna_main.cc
+++ b/source/blender/makesrna/intern/rna_main.cc
@@ -120,9 +120,6 @@ RNA_MAIN_LISTBASE_FUNCS_DEF(pointclouds)
 RNA_MAIN_LISTBASE_FUNCS_DEF(scenes)
 RNA_MAIN_LISTBASE_FUNCS_DEF(screens)
 RNA_MAIN_LISTBASE_FUNCS_DEF(shapekeys)
-#  ifdef WITH_SIMULATION_DATABLOCK
-RNA_MAIN_LISTBASE_FUNCS_DEF(simulations)
-#  endif
 RNA_MAIN_LISTBASE_FUNCS_DEF(sounds)
 RNA_MAIN_LISTBASE_FUNCS_DEF(speakers)
 RNA_MAIN_LISTBASE_FUNCS_DEF(texts)
@@ -408,14 +405,6 @@ void RNA_def_main(BlenderRNA *brna)
        "Volumes",
        "Volume data-blocks",
        RNA_def_main_volumes},
-#  ifdef WITH_SIMULATION_DATABLOCK
-      {"simulations",
-       "Simulation",
-       "rna_Main_simulations_begin",
-       "Simulations",
-       "Simulation data-blocks",
-       RNA_def_main_simulations},
-#  endif
       {nullptr, nullptr, nullptr, nullptr, nullptr, nullptr},
   };
 
diff --git a/source/blender/makesrna/intern/rna_main_api.cc b/source/blender/makesrna/intern/rna_main_api.cc
index 68f095023ee..8635c26470d 100644
--- a/source/blender/makesrna/intern/rna_main_api.cc
+++ b/source/blender/makesrna/intern/rna_main_api.cc
@@ -53,7 +53,6 @@
 #  include "BKE_particle.h"
 #  include "BKE_pointcloud.h"
 #  include "BKE_scene.h"
-#  include "BKE_simulation.h"
 #  include "BKE_sound.h"
 #  include "BKE_speaker.h"
 #  include "BKE_text.h"
@@ -84,7 +83,6 @@
 #  include "DNA_node_types.h"
 #  include "DNA_particle_types.h"
 #  include "DNA_pointcloud_types.h"
-#  include "DNA_simulation_types.h"
 #  include "DNA_sound_types.h"
 #  include "DNA_speaker_types.h"
 #  include "DNA_text_types.h"
@@ -791,21 +789,6 @@ static Volume *rna_Main_volumes_new(Main *bmain, const char *name)
   return volume;
 }
 
-#  ifdef WITH_SIMULATION_DATABLOCK
-static Simulation *rna_Main_simulations_new(Main *bmain, const char *name)
-{
-  char safe_name[MAX_ID_NAME - 2];
-  rna_idname_validate(name, safe_name);
-
-  Simulation *simulation = static_cast<Simulation *>(BKE_simulation_add(bmain, safe_name));
-  id_us_min(&simulation->id);
-
-  WM_main_add_notifier(NC_ID | NA_ADDED, nullptr);
-
-  return simulation;
-}
-#  endif
-
 /* tag functions, all the same */
 #  define RNA_MAIN_ID_TAG_FUNCS_DEF(_func_name, _listbase_name, _id_type) \
     static void rna_Main_##_func_name##_tag(Main *bmain, bool value) \
@@ -851,9 +834,6 @@ RNA_MAIN_ID_TAG_FUNCS_DEF(lightprobes, lightprobes, ID_LP)
 RNA_MAIN_ID_TAG_FUNCS_DEF(hair_curves, hair_curves, ID_CV)
 RNA_MAIN_ID_TAG_FUNCS_DEF(pointclouds, pointclouds, ID_PT)
 RNA_MAIN_ID_TAG_FUNCS_DEF(volumes, volumes, ID_VO)
-#  ifdef WITH_SIMULATION_DATABLOCK
-RNA_MAIN_ID_TAG_FUNCS_DEF(simulations, simulations, ID_SIM)
-#  endif
 
 #  undef RNA_MAIN_ID_TAG_FUNCS_DEF
 
@@ -2399,46 +2379,4 @@ void RNA_def_main_volumes(BlenderRNA *brna, PropertyRNA *cprop)
   RNA_def_parameter_flags(parm, PropertyFlag(0), PARM_REQUIRED);
 }
 
-#  ifdef WITH_SIMULATION_DATABLOCK
-void RNA_def_main_simulations(BlenderRNA *brna, PropertyRNA *cprop)
-{
-  StructRNA *srna;
-  FunctionRNA *func;
-  PropertyRNA *parm;
-
-  RNA_def_property_srna(cprop, "BlendDataSimulations");
-  srna = RNA_def_struct(brna, "BlendDataSimulations", nullptr);
-  RNA_def_struct_sdna(srna, "Main");
-  RNA_def_struct_ui_text(srna, "Main Simulations", "Collection of simulations");
-
-  func = RNA_def_function(srna, "new", "rna_Main_simulations_new");
-  RNA_def_function_ui_description(func, "Add a new simulation to the main database");
-  parm = RNA_def_string(func, "name", "Simulation", 0, "", "New name for the data-block");
-  RNA_def_parameter_flags(parm, PropertyFlag(0), PARM_REQUIRED);
-  /* return type */
-  parm = RNA_def_pointer(func, "simulation", "Simulation", "", "New simulation data-block");
-  RNA_def_function_return(func, parm);
-
-  func = RNA_def_function(srna, "remove", "rna_Main_ID_remove");
-  RNA_def_function_flag(func, FUNC_USE_REPORTS);
-  RNA_def_function_ui_description(func, "Remove a simulation from the current blendfile");
-  parm = RNA_def_pointer(func, "simulation", "Simulation", "", "Simulation to remove");
-  RNA_def_parameter_flags(parm, PROP_NEVER_NULL, PARM_REQUIRED | PARM_RNAPTR);
-  RNA_def_parameter_clear_flags(parm, PROP_THICK_WRAP, ParameterFlag(0));
-  RNA_def_boolean(
-      func, "do_unlink", true, "", "Unlink all usages of this simulation before deleting it");
-  RNA_def_boolean(func,
-                  "do_id_user",
-                  true,
-                  "",
-                  "Decrement user counter of all datablocks used by this simulation data");
-  RNA_def_boolean(
-      func, "do_ui_user", true, "", "Make sure interface does not reference this simulation data");
-
-  func = RNA_def_function(srna, "tag", "rna_Main_simulations_tag");
-  parm = RNA_def_boolean(func, "value", 0, "Value", "");
-  RNA_def_parameter_flags(parm, PropertyFlag(0), PARM_REQUIRED);
-}
-#  endif
-
 #endif
diff --git a/source/blender/makesrna/intern/rna_simulation.cc b/source/blender/makesrna/intern/rna_simulation.cc
deleted file mode 100644
index 82a41ada7b3..00000000000
--- a/source/blender/makesrna/intern/rna_simulation.cc
+++ /dev/null
@@ -1,46 +0,0 @@
-/* SPDX-FileCopyrightText: 2023 Blender Foundation
- *
- * SPDX-License-Identifier: GPL-2.0-or-later */
-
-/** \file
- * \ingroup RNA
- */
-
-#include <stdlib.h>
-
-#include "RNA_define.h"
-#include "RNA_enum_types.h"
-
-#include "DNA_simulation_types.h"
-
-#include "rna_internal.h"
-
-#ifdef RNA_RUNTIME
-
-#else
-
-static void rna_def_simulation(BlenderRNA *brna)
-{
-  StructRNA *srna;
-  PropertyRNA *prop;
-
-  srna = RNA_def_struct(brna, "Simulation", "ID");
-  RNA_def_struct_ui_text(srna, "Simulation", "Simulation data-block");
-  RNA_def_struct_ui_icon(srna, ICON_PHYSICS); /* TODO: Use correct icon. */
-
-  prop = RNA_def_property(srna, "node_tree", PROP_POINTER, PROP_NONE);
-  RNA_def_property_pointer_sdna(prop, nullptr, "nodetree");
-  RNA_def_property_clear_flag(prop, PROP_PTR_NO_OWNERSHIP);
-  RNA_def_property_override_flag(prop, PROPOVERRIDE_OVERRIDABLE_LIBRARY);
-  RNA_def_property_ui_text(prop, "Node Tree", "Node tree defining the simulation");
-
-  /* common */
-  rna_def_animdata_common(srna);
-}
-
-void RNA_def_simulation(BlenderRNA *brna)
-{
-  rna_def_simulation(brna);
-}
-
-#endif
diff --git a/source/blender/modifiers/intern/MOD_nodes.cc b/source/blender/modifiers/intern/MOD_nodes.cc
index 04a272aaf14..f0aa23e99e1 100644
--- a/source/blender/modifiers/intern/MOD_nodes.cc
+++ b/source/blender/modifiers/intern/MOD_nodes.cc
@@ -55,7 +55,6 @@
 #include "BKE_object.h"
 #include "BKE_pointcloud.h"
 #include "BKE_screen.h"
-#include "BKE_simulation.h"
 #include "BKE_simulation_state.hh"
 #include "BKE_simulation_state_serialize.hh"
 #include "BKE_workspace.h"