Cleanup: Move object_modifier.c to C++

This allows using C++ only APIs/data structures, and potentially
simplifies adding support to apply modifiers for the Curves object.

1 files changed, 3348 insertions, 0 deletions

diff --git a/source/blender/editors/object/object_modifier.cc b/source/blender/editors/object/object_modifier.cc
new file mode 100644
index 00000000000..f7543c97903
--- /dev/null
+++ b/source/blender/editors/object/object_modifier.cc
@@ -0,0 +1,3348 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2001-2002 NaN Holding BV. All rights reserved. */
+
+/** \file
+ * \ingroup edobj
+ */
+
+#include <cmath>
+#include <cstdio>
+#include <cstdlib>
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_anim_types.h"
+#include "DNA_armature_types.h"
+#include "DNA_curve_types.h"
+#include "DNA_dynamicpaint_types.h"
+#include "DNA_fluid_types.h"
+#include "DNA_key_types.h"
+#include "DNA_lattice_types.h"
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_force_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_space_types.h"
+
+#include "BLI_bitmap.h"
+#include "BLI_listbase.h"
+#include "BLI_math.h"
+#include "BLI_path_util.h"
+#include "BLI_string.h"
+#include "BLI_string_utf8.h"
+#include "BLI_utildefines.h"
+
+#include "BKE_DerivedMesh.h"
+#include "BKE_animsys.h"
+#include "BKE_armature.h"
+#include "BKE_context.h"
+#include "BKE_curve.h"
+#include "BKE_curves.h"
+#include "BKE_displist.h"
+#include "BKE_editmesh.h"
+#include "BKE_effect.h"
+#include "BKE_global.h"
+#include "BKE_gpencil_modifier.h"
+#include "BKE_key.h"
+#include "BKE_lattice.h"
+#include "BKE_lib_id.h"
+#include "BKE_main.h"
+#include "BKE_material.h"
+#include "BKE_mesh.h"
+#include "BKE_mesh_mapping.h"
+#include "BKE_mesh_runtime.h"
+#include "BKE_modifier.h"
+#include "BKE_multires.h"
+#include "BKE_object.h"
+#include "BKE_object_deform.h"
+#include "BKE_ocean.h"
+#include "BKE_paint.h"
+#include "BKE_particle.h"
+#include "BKE_pointcloud.h"
+#include "BKE_report.h"
+#include "BKE_scene.h"
+#include "BKE_softbody.h"
+#include "BKE_volume.h"
+
+#include "DEG_depsgraph.h"
+#include "DEG_depsgraph_build.h"
+#include "DEG_depsgraph_query.h"
+
+#include "BLT_translation.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+#include "RNA_enum_types.h"
+#include "RNA_prototypes.h"
+
+#include "ED_armature.h"
+#include "ED_mesh.h"
+#include "ED_object.h"
+#include "ED_screen.h"
+#include "ED_sculpt.h"
+
+#include "MOD_nodes.h"
+
+#include "UI_interface.h"
+
+#include "WM_api.h"
+#include "WM_types.h"
+
+#include "object_intern.h"
+
+static void modifier_skin_customdata_delete(struct Object *ob);
+
+/* ------------------------------------------------------------------- */
+/** \name Public Api
+ * \{ */
+
+static void object_force_modifier_update_for_bind(Depsgraph *depsgraph, Object *ob)
+{
+  Scene *scene_eval = DEG_get_evaluated_scene(depsgraph);
+  Object *ob_eval = DEG_get_evaluated_object(depsgraph, ob);
+  BKE_object_eval_reset(ob_eval);
+  if (ob->type == OB_MESH) {
+    Mesh *me_eval = mesh_create_eval_final(depsgraph, scene_eval, ob_eval, &CD_MASK_BAREMESH);
+    BKE_mesh_eval_delete(me_eval);
+  }
+  else if (ob->type == OB_LATTICE) {
+    BKE_lattice_modifiers_calc(depsgraph, scene_eval, ob_eval);
+  }
+  else if (ob->type == OB_MBALL) {
+    BKE_displist_make_mball(depsgraph, scene_eval, ob_eval);
+  }
+  else if (ELEM(ob->type, OB_CURVES_LEGACY, OB_SURF, OB_FONT)) {
+    BKE_displist_make_curveTypes(depsgraph, scene_eval, ob_eval, false);
+  }
+  else if (ob->type == OB_GPENCIL) {
+    BKE_gpencil_modifiers_calc(depsgraph, scene_eval, ob_eval);
+  }
+  else if (ob->type == OB_CURVES) {
+    BKE_curves_data_update(depsgraph, scene_eval, ob);
+  }
+  else if (ob->type == OB_POINTCLOUD) {
+    BKE_pointcloud_data_update(depsgraph, scene_eval, ob);
+  }
+  else if (ob->type == OB_VOLUME) {
+    BKE_volume_data_update(depsgraph, scene_eval, ob);
+  }
+}
+
+static void object_force_modifier_bind_simple_options(Depsgraph *depsgraph,
+                                                      Object *object,
+                                                      ModifierData *md)
+{
+  ModifierData *md_eval = (ModifierData *)BKE_modifier_get_evaluated(depsgraph, object, md);
+  const int mode = md_eval->mode;
+  md_eval->mode |= eModifierMode_Realtime;
+  object_force_modifier_update_for_bind(depsgraph, object);
+  md_eval->mode = mode;
+}
+
+ModifierData *ED_object_modifier_add(
+    ReportList *reports, Main *bmain, Scene *scene, Object *ob, const char *name, int type)
+{
+  ModifierData *md = nullptr, *new_md = nullptr;
+  const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)type);
+
+  /* Check compatibility of modifier [T25291, T50373]. */
+  if (!BKE_object_support_modifier_type_check(ob, type)) {
+    BKE_reportf(reports, RPT_WARNING, "Modifiers cannot be added to object '%s'", ob->id.name + 2);
+    return nullptr;
+  }
+
+  if (mti->flags & eModifierTypeFlag_Single) {
+    if (BKE_modifiers_findby_type(ob, (ModifierType)type)) {
+      BKE_report(reports, RPT_WARNING, "Only one modifier of this type is allowed");
+      return nullptr;
+    }
+  }
+
+  if (type == eModifierType_ParticleSystem) {
+    /* don't need to worry about the new modifier's name, since that is set to the number
+     * of particle systems which shouldn't have too many duplicates
+     */
+    new_md = object_add_particle_system(bmain, scene, ob, name);
+  }
+  else {
+    /* get new modifier data to add */
+    new_md = BKE_modifier_new(type);
+
+    if (mti->flags & eModifierTypeFlag_RequiresOriginalData) {
+      md = static_cast<ModifierData *>(ob->modifiers.first);
+
+      while (md &&
+             BKE_modifier_get_info((ModifierType)md->type)->type == eModifierTypeType_OnlyDeform) {
+        md = md->next;
+      }
+
+      BLI_insertlinkbefore(&ob->modifiers, md, new_md);
+    }
+    else {
+      BLI_addtail(&ob->modifiers, new_md);
+    }
+
+    if (name) {
+      BLI_strncpy_utf8(new_md->name, name, sizeof(new_md->name));
+    }
+
+    /* make sure modifier data has unique name */
+
+    BKE_modifier_unique_name(&ob->modifiers, new_md);
+
+    /* special cases */
+    if (type == eModifierType_Softbody) {
+      if (!ob->soft) {
+        ob->soft = sbNew();
+        ob->softflag |= OB_SB_GOAL | OB_SB_EDGES;
+      }
+    }
+    else if (type == eModifierType_Collision) {
+      if (!ob->pd) {
+        ob->pd = BKE_partdeflect_new(0);
+      }
+
+      ob->pd->deflect = 1;
+    }
+    else if (type == eModifierType_Surface) {
+      /* pass */
+    }
+    else if (type == eModifierType_Multires) {
+      /* set totlvl from existing MDISPS layer if object already had it */
+      multiresModifier_set_levels_from_disps((MultiresModifierData *)new_md, ob);
+
+      if (ob->mode & OB_MODE_SCULPT) {
+        /* ensure that grid paint mask layer is created */
+        BKE_sculpt_mask_layers_ensure(ob, (MultiresModifierData *)new_md);
+      }
+    }
+    else if (type == eModifierType_Skin) {
+      /* ensure skin-node customdata exists */
+      BKE_mesh_ensure_skin_customdata(static_cast<Mesh *>(ob->data));
+    }
+  }
+
+  BKE_object_modifier_set_active(ob, new_md);
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  DEG_relations_tag_update(bmain);
+
+  return new_md;
+}
+
+/* Return true if the object has a modifier of type 'type' other than
+ * the modifier pointed to be 'exclude', otherwise returns false. */
+static bool object_has_modifier(const Object *ob, const ModifierData *exclude, ModifierType type)
+{
+  LISTBASE_FOREACH (ModifierData *, md, &ob->modifiers) {
+    if ((md != exclude) && (md->type == type)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool ED_object_iter_other(Main *bmain,
+                          Object *orig_ob,
+                          const bool include_orig,
+                          bool (*callback)(Object *ob, void *callback_data),
+                          void *callback_data)
+{
+  ID *ob_data_id = static_cast<ID *>(orig_ob->data);
+  int users = ob_data_id->us;
+
+  if (ob_data_id->flag & LIB_FAKEUSER) {
+    users--;
+  }
+
+  /* First check that the object's data has multiple users */
+  if (users > 1) {
+    Object *ob;
+    int totfound = include_orig ? 0 : 1;
+
+    for (ob = static_cast<Object *>(bmain->objects.first); ob && totfound < users;
+         ob = reinterpret_cast<Object *>(ob->id.next)) {
+      if (((ob != orig_ob) || include_orig) && (ob->data == orig_ob->data)) {
+        if (callback(ob, callback_data)) {
+          return true;
+        }
+
+        totfound++;
+      }
+    }
+  }
+  else if (include_orig) {
+    return callback(orig_ob, callback_data);
+  }
+
+  return false;
+}
+
+static bool object_has_modifier_cb(Object *ob, void *data)
+{
+  ModifierType type = *((ModifierType *)data);
+
+  return object_has_modifier(ob, nullptr, type);
+}
+
+bool ED_object_multires_update_totlevels_cb(Object *ob, void *totlevel_v)
+{
+  int totlevel = *((char *)totlevel_v);
+
+  LISTBASE_FOREACH (ModifierData *, md, &ob->modifiers) {
+    if (md->type == eModifierType_Multires) {
+      multires_set_tot_level(ob, (MultiresModifierData *)md, totlevel);
+      DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+    }
+  }
+  return false;
+}
+
+/* Return true if no modifier of type 'type' other than 'exclude' */
+static bool object_modifier_safe_to_delete(Main *bmain,
+                                           Object *ob,
+                                           ModifierData *exclude,
+                                           ModifierType type)
+{
+  return (!object_has_modifier(ob, exclude, type) &&
+          !ED_object_iter_other(bmain, ob, false, object_has_modifier_cb, &type));
+}
+
+static bool object_modifier_remove(
+    Main *bmain, Scene *scene, Object *ob, ModifierData *md, bool *r_sort_depsgraph)
+{
+  /* It seems on rapid delete it is possible to
+   * get called twice on same modifier, so make
+   * sure it is in list. */
+  if (BLI_findindex(&ob->modifiers, md) == -1) {
+    return false;
+  }
+
+  /* special cases */
+  if (md->type == eModifierType_ParticleSystem) {
+    object_remove_particle_system(bmain, scene, ob, ((ParticleSystemModifierData *)md)->psys);
+    return true;
+  }
+
+  if (md->type == eModifierType_Softbody) {
+    if (ob->soft) {
+      sbFree(ob);
+      ob->softflag = 0; /* TODO(Sybren): this should probably be moved into sbFree() */
+    }
+  }
+  else if (md->type == eModifierType_Collision) {
+    if (ob->pd) {
+      ob->pd->deflect = 0;
+    }
+
+    *r_sort_depsgraph = true;
+  }
+  else if (md->type == eModifierType_Surface) {
+    *r_sort_depsgraph = true;
+  }
+  else if (md->type == eModifierType_Multires) {
+    /* Delete MDisps layer if not used by another multires modifier */
+    if (object_modifier_safe_to_delete(bmain, ob, md, eModifierType_Multires)) {
+      multires_customdata_delete(static_cast<Mesh *>(ob->data));
+    }
+  }
+  else if (md->type == eModifierType_Skin) {
+    /* Delete MVertSkin layer if not used by another skin modifier */
+    if (object_modifier_safe_to_delete(bmain, ob, md, eModifierType_Skin)) {
+      modifier_skin_customdata_delete(ob);
+    }
+  }
+
+  if (ELEM(md->type, eModifierType_Softbody, eModifierType_Cloth) &&
+      BLI_listbase_is_empty(&ob->particlesystem)) {
+    ob->mode &= ~OB_MODE_PARTICLE_EDIT;
+  }
+
+  BKE_modifier_remove_from_list(ob, md);
+  BKE_modifier_free(md);
+  BKE_object_free_derived_caches(ob);
+
+  return true;
+}
+
+bool ED_object_modifier_remove(
+    ReportList *reports, Main *bmain, Scene *scene, Object *ob, ModifierData *md)
+{
+  bool sort_depsgraph = false;
+
+  bool ok = object_modifier_remove(bmain, scene, ob, md, &sort_depsgraph);
+
+  if (!ok) {
+    BKE_reportf(reports, RPT_ERROR, "Modifier '%s' not in object '%s'", md->name, ob->id.name);
+    return false;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  DEG_relations_tag_update(bmain);
+
+  return true;
+}
+
+void ED_object_modifier_clear(Main *bmain, Scene *scene, Object *ob)
+{
+  ModifierData *md = static_cast<ModifierData *>(ob->modifiers.first);
+  bool sort_depsgraph = false;
+
+  if (!md) {
+    return;
+  }
+
+  while (md) {
+    ModifierData *next_md = md->next;
+
+    object_modifier_remove(bmain, scene, ob, md, &sort_depsgraph);
+
+    md = next_md;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  DEG_relations_tag_update(bmain);
+}
+
+bool ED_object_modifier_move_up(ReportList *reports, Object *ob, ModifierData *md)
+{
+  if (md->prev) {
+    const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md->type);
+
+    if (mti->type != eModifierTypeType_OnlyDeform) {
+      const ModifierTypeInfo *nmti = BKE_modifier_get_info((ModifierType)md->prev->type);
+
+      if (nmti->flags & eModifierTypeFlag_RequiresOriginalData) {
+        BKE_report(reports, RPT_WARNING, "Cannot move above a modifier requiring original data");
+        return false;
+      }
+    }
+
+    BLI_listbase_swaplinks(&ob->modifiers, md, md->prev);
+  }
+  else {
+    BKE_report(reports, RPT_WARNING, "Cannot move modifier beyond the start of the list");
+    return false;
+  }
+
+  return true;
+}
+
+bool ED_object_modifier_move_down(ReportList *reports, Object *ob, ModifierData *md)
+{
+  if (md->next) {
+    const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md->type);
+
+    if (mti->flags & eModifierTypeFlag_RequiresOriginalData) {
+      const ModifierTypeInfo *nmti = BKE_modifier_get_info((ModifierType)md->next->type);
+
+      if (nmti->type != eModifierTypeType_OnlyDeform) {
+        BKE_report(reports, RPT_WARNING, "Cannot move beyond a non-deforming modifier");
+        return false;
+      }
+    }
+
+    BLI_listbase_swaplinks(&ob->modifiers, md, md->next);
+  }
+  else {
+    BKE_report(reports, RPT_WARNING, "Cannot move modifier beyond the end of the list");
+    return false;
+  }
+
+  return true;
+}
+
+bool ED_object_modifier_move_to_index(ReportList *reports,
+                                      Object *ob,
+                                      ModifierData *md,
+                                      const int index)
+{
+  BLI_assert(md != nullptr);
+  BLI_assert(index >= 0);
+  if (index >= BLI_listbase_count(&ob->modifiers)) {
+    BKE_report(reports, RPT_WARNING, "Cannot move modifier beyond the end of the stack");
+    return false;
+  }
+
+  int md_index = BLI_findindex(&ob->modifiers, md);
+  BLI_assert(md_index != -1);
+  if (md_index < index) {
+    /* Move modifier down in list. */
+    for (; md_index < index; md_index++) {
+      if (!ED_object_modifier_move_down(reports, ob, md)) {
+        break;
+      }
+    }
+  }
+  else {
+    /* Move modifier up in list. */
+    for (; md_index > index; md_index--) {
+      if (!ED_object_modifier_move_up(reports, ob, md)) {
+        break;
+      }
+    }
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_main_add_notifier(NC_OBJECT | ND_MODIFIER, ob);
+
+  return true;
+}
+
+void ED_object_modifier_link(bContext *C, Object *ob_dst, Object *ob_src)
+{
+  BKE_object_link_modifiers(ob_dst, ob_src);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob_dst);
+  DEG_id_tag_update(&ob_dst->id, ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY | ID_RECALC_ANIMATION);
+
+  Main *bmain = CTX_data_main(C);
+  DEG_relations_tag_update(bmain);
+}
+
+void ED_object_modifier_copy_to_object(bContext *C,
+                                       Object *ob_dst,
+                                       Object *ob_src,
+                                       ModifierData *md)
+{
+  BKE_object_copy_modifier(CTX_data_main(C), CTX_data_scene(C), ob_dst, ob_src, md);
+  WM_main_add_notifier(NC_OBJECT | ND_MODIFIER, ob_dst);
+  DEG_id_tag_update(&ob_dst->id, ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY | ID_RECALC_ANIMATION);
+
+  Main *bmain = CTX_data_main(C);
+  DEG_relations_tag_update(bmain);
+}
+
+bool ED_object_modifier_convert(ReportList *UNUSED(reports),
+                                Main *bmain,
+                                Depsgraph *depsgraph,
+                                ViewLayer *view_layer,
+                                Object *ob,
+                                ModifierData *md)
+{
+  int cvert = 0;
+
+  if (md->type != eModifierType_ParticleSystem) {
+    return false;
+  }
+  if (ob && ob->mode & OB_MODE_PARTICLE_EDIT) {
+    return false;
+  }
+
+  ParticleSystem *psys_orig = ((ParticleSystemModifierData *)md)->psys;
+  ParticleSettings *part = psys_orig->part;
+
+  if (part->ren_as != PART_DRAW_PATH) {
+    return false;
+  }
+  ParticleSystem *psys_eval = psys_eval_get(depsgraph, ob, psys_orig);
+  if (psys_eval->pathcache == nullptr) {
+    return false;
+  }
+
+  int part_num = psys_eval->totcached;
+  int child_num = psys_eval->totchildcache;
+
+  if (child_num && (part->draw & PART_DRAW_PARENT) == 0) {
+    part_num = 0;
+  }
+
+  /* count */
+  int verts_num = 0, edges_num = 0;
+  ParticleCacheKey **cache = psys_eval->pathcache;
+  for (int a = 0; a < part_num; a++) {
+    ParticleCacheKey *key = cache[a];
+
+    if (key->segments > 0) {
+      verts_num += key->segments + 1;
+      edges_num += key->segments;
+    }
+  }
+
+  cache = psys_eval->childcache;
+  for (int a = 0; a < child_num; a++) {
+    ParticleCacheKey *key = cache[a];
+
+    if (key->segments > 0) {
+      verts_num += key->segments + 1;
+      edges_num += key->segments;
+    }
+  }
+
+  if (verts_num == 0) {
+    return false;
+  }
+
+  /* add new mesh */
+  Object *obn = BKE_object_add(bmain, view_layer, OB_MESH, nullptr);
+  Mesh *me = static_cast<Mesh *>(obn->data);
+
+  me->totvert = verts_num;
+  me->totedge = edges_num;
+
+  me->mvert = (MVert *)CustomData_add_layer(&me->vdata, CD_MVERT, CD_CALLOC, nullptr, verts_num);
+  me->medge = (MEdge *)CustomData_add_layer(&me->edata, CD_MEDGE, CD_CALLOC, nullptr, edges_num);
+  me->mface = (MFace *)CustomData_add_layer(&me->fdata, CD_MFACE, CD_CALLOC, nullptr, 0);
+
+  MVert *mvert = me->mvert;
+  MEdge *medge = me->medge;
+
+  /* copy coordinates */
+  cache = psys_eval->pathcache;
+  for (int a = 0; a < part_num; a++) {
+    ParticleCacheKey *key = cache[a];
+    int kmax = key->segments;
+    for (int k = 0; k <= kmax; k++, key++, cvert++, mvert++) {
+      copy_v3_v3(mvert->co, key->co);
+      if (k) {
+        medge->v1 = cvert - 1;
+        medge->v2 = cvert;
+        medge->flag = ME_EDGEDRAW | ME_EDGERENDER | ME_LOOSEEDGE;
+        medge++;
+      }
+      else {
+        /* cheap trick to select the roots */
+        mvert->flag |= SELECT;
+      }
+    }
+  }
+
+  cache = psys_eval->childcache;
+  for (int a = 0; a < child_num; a++) {
+    ParticleCacheKey *key = cache[a];
+    int kmax = key->segments;
+    for (int k = 0; k <= kmax; k++, key++, cvert++, mvert++) {
+      copy_v3_v3(mvert->co, key->co);
+      if (k) {
+        medge->v1 = cvert - 1;
+        medge->v2 = cvert;
+        medge->flag = ME_EDGEDRAW | ME_EDGERENDER | ME_LOOSEEDGE;
+        medge++;
+      }
+      else {
+        /* cheap trick to select the roots */
+        mvert->flag |= SELECT;
+      }
+    }
+  }
+
+  DEG_relations_tag_update(bmain);
+
+  return true;
+}
+
+/* Gets mesh for the modifier which corresponds to an evaluated state. */
+static Mesh *modifier_apply_create_mesh_for_modifier(Depsgraph *depsgraph,
+                                                     Object *object,
+                                                     ModifierData *md_eval,
+                                                     bool use_virtual_modifiers,
+                                                     bool build_shapekey_layers)
+{
+  Scene *scene_eval = DEG_get_evaluated_scene(depsgraph);
+  Object *object_eval = DEG_get_evaluated_object(depsgraph, object);
+  Mesh *mesh_applied = BKE_mesh_create_derived_for_modifier(
+      depsgraph, scene_eval, object_eval, md_eval, use_virtual_modifiers, build_shapekey_layers);
+  return mesh_applied;
+}
+
+static bool modifier_apply_shape(Main *bmain,
+                                 ReportList *reports,
+                                 Depsgraph *depsgraph,
+                                 Scene *scene,
+                                 Object *ob,
+                                 ModifierData *md_eval)
+{
+  const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md_eval->type);
+
+  if (mti->isDisabled && mti->isDisabled(scene, md_eval, false)) {
+    BKE_report(reports, RPT_ERROR, "Modifier is disabled, skipping apply");
+    return false;
+  }
+
+  /* We could investigate using the #CD_ORIGINDEX layer
+   * to support other kinds of modifiers besides deforming modifiers.
+   * as this is done in many other places, see: #BKE_mesh_foreach_mapped_vert_coords_get.
+   *
+   * This isn't high priority in practice since most modifiers users
+   * want to apply as a shape are deforming modifiers.
+   *
+   * If a compelling use-case comes up where we want to support other kinds of modifiers
+   * we can look into supporting them. */
+
+  if (ob->type == OB_MESH) {
+    Mesh *me = static_cast<Mesh *>(ob->data);
+    Key *key = me->key;
+
+    if (!BKE_modifier_is_same_topology(md_eval) || mti->type == eModifierTypeType_NonGeometrical) {
+      BKE_report(reports, RPT_ERROR, "Only deforming modifiers can be applied to shapes");
+      return false;
+    }
+
+    Mesh *mesh_applied = modifier_apply_create_mesh_for_modifier(
+        depsgraph, ob, md_eval, true, false);
+    if (!mesh_applied) {
+      BKE_report(reports, RPT_ERROR, "Modifier is disabled or returned error, skipping apply");
+      return false;
+    }
+
+    if (key == nullptr) {
+      key = me->key = BKE_key_add(bmain, (ID *)me);
+      key->type = KEY_RELATIVE;
+      /* if that was the first key block added, then it was the basis.
+       * Initialize it with the mesh, and add another for the modifier */
+      KeyBlock *kb = BKE_keyblock_add(key, nullptr);
+      BKE_keyblock_convert_from_mesh(me, key, kb);
+    }
+
+    KeyBlock *kb = BKE_keyblock_add(key, md_eval->name);
+    BKE_mesh_nomain_to_meshkey(mesh_applied, me, kb);
+
+    BKE_id_free(nullptr, mesh_applied);
+  }
+  else {
+    /* TODO: implement for curves, point clouds and volumes. */
+    BKE_report(reports, RPT_ERROR, "Cannot apply modifier for this object type");
+    return false;
+  }
+  return true;
+}
+
+static bool modifier_apply_obdata(
+    ReportList *reports, Depsgraph *depsgraph, Scene *scene, Object *ob, ModifierData *md_eval)
+{
+  const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md_eval->type);
+
+  if (mti->isDisabled && mti->isDisabled(scene, md_eval, false)) {
+    BKE_report(reports, RPT_ERROR, "Modifier is disabled, skipping apply");
+    return false;
+  }
+
+  if (ob->type == OB_MESH) {
+    Mesh *me = static_cast<Mesh *>(ob->data);
+    MultiresModifierData *mmd = find_multires_modifier_before(scene, md_eval);
+
+    if (me->key && mti->type != eModifierTypeType_NonGeometrical) {
+      BKE_report(reports, RPT_ERROR, "Modifier cannot be applied to a mesh with shape keys");
+      return false;
+    }
+
+    /* Multires: ensure that recent sculpting is applied */
+    if (md_eval->type == eModifierType_Multires) {
+      multires_force_sculpt_rebuild(ob);
+    }
+
+    if (mmd && mmd->totlvl && mti->type == eModifierTypeType_OnlyDeform) {
+      if (!multiresModifier_reshapeFromDeformModifier(depsgraph, ob, mmd, md_eval)) {
+        BKE_report(reports, RPT_ERROR, "Multires modifier returned error, skipping apply");
+        return false;
+      }
+    }
+    else {
+      Mesh *mesh_applied = modifier_apply_create_mesh_for_modifier(
+          depsgraph, ob, md_eval, true, true);
+      if (!mesh_applied) {
+        BKE_report(reports, RPT_ERROR, "Modifier returned error, skipping apply");
+        return false;
+      }
+
+      Main *bmain = DEG_get_bmain(depsgraph);
+      BKE_object_material_from_eval_data(bmain, ob, &mesh_applied->id);
+      BKE_mesh_nomain_to_mesh(mesh_applied, me, ob, &CD_MASK_MESH, true);
+
+      /* Anonymous attributes shouldn't be available on the applied geometry. */
+      BKE_mesh_anonymous_attributes_remove(me);
+
+      if (md_eval->type == eModifierType_Multires) {
+        multires_customdata_delete(me);
+      }
+    }
+  }
+  else if (ELEM(ob->type, OB_CURVES_LEGACY, OB_SURF)) {
+    Object *object_eval = DEG_get_evaluated_object(depsgraph, ob);
+    Curve *curve = static_cast<Curve *>(ob->data);
+    Curve *curve_eval = static_cast<Curve *>(object_eval->data);
+    ModifierEvalContext mectx = {depsgraph, object_eval, (ModifierApplyFlag)0};
+
+    if (ELEM(mti->type, eModifierTypeType_Constructive, eModifierTypeType_Nonconstructive)) {
+      BKE_report(
+          reports, RPT_ERROR, "Transform curve to mesh in order to apply constructive modifiers");
+      return false;
+    }
+
+    BKE_report(reports,
+               RPT_INFO,
+               "Applied modifier only changed CV points, not tessellated/bevel vertices");
+
+    int verts_num;
+    float(*vertexCos)[3] = BKE_curve_nurbs_vert_coords_alloc(&curve_eval->nurb, &verts_num);
+    mti->deformVerts(md_eval, &mectx, nullptr, vertexCos, verts_num);
+    BKE_curve_nurbs_vert_coords_apply(&curve->nurb, vertexCos, false);
+
+    MEM_freeN(vertexCos);
+
+    DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  }
+  else if (ob->type == OB_LATTICE) {
+    Object *object_eval = DEG_get_evaluated_object(depsgraph, ob);
+    Lattice *lattice = static_cast<Lattice *>(ob->data);
+    ModifierEvalContext mectx = {depsgraph, object_eval, (ModifierApplyFlag)0};
+
+    if (ELEM(mti->type, eModifierTypeType_Constructive, eModifierTypeType_Nonconstructive)) {
+      BKE_report(reports, RPT_ERROR, "Constructive modifiers cannot be applied");
+      return false;
+    }
+
+    int verts_num;
+    float(*vertexCos)[3] = BKE_lattice_vert_coords_alloc(lattice, &verts_num);
+    mti->deformVerts(md_eval, &mectx, nullptr, vertexCos, verts_num);
+    BKE_lattice_vert_coords_apply(lattice, vertexCos);
+
+    MEM_freeN(vertexCos);
+
+    DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  }
+  else {
+    /* TODO: implement for curves, point clouds and volumes. */
+    BKE_report(reports, RPT_ERROR, "Cannot apply modifier for this object type");
+    return false;
+  }
+
+  /* lattice modifier can be applied to particle system too */
+  if (ob->particlesystem.first) {
+    LISTBASE_FOREACH (ParticleSystem *, psys, &ob->particlesystem) {
+      if (psys->part->type != PART_HAIR) {
+        continue;
+      }
+
+      psys_apply_hair_lattice(depsgraph, scene, ob, psys);
+    }
+  }
+
+  return true;
+}
+
+bool ED_object_modifier_apply(Main *bmain,
+                              ReportList *reports,
+                              Depsgraph *depsgraph,
+                              Scene *scene,
+                              Object *ob,
+                              ModifierData *md,
+                              int mode,
+                              bool keep_modifier)
+{
+  if (BKE_object_is_in_editmode(ob)) {
+    BKE_report(reports, RPT_ERROR, "Modifiers cannot be applied in edit mode");
+    return false;
+  }
+  if (mode != MODIFIER_APPLY_SHAPE && ID_REAL_USERS(ob->data) > 1) {
+    BKE_report(reports, RPT_ERROR, "Modifiers cannot be applied to multi-user data");
+    return false;
+  }
+  if ((ob->mode & OB_MODE_SCULPT) && (find_multires_modifier_before(scene, md)) &&
+      (BKE_modifier_is_same_topology(md) == false)) {
+    BKE_report(reports,
+               RPT_ERROR,
+               "Constructive modifier cannot be applied to multi-res data in sculpt mode");
+    return false;
+  }
+
+  if (md != ob->modifiers.first) {
+    BKE_report(reports, RPT_INFO, "Applied modifier was not first, result may not be as expected");
+  }
+
+  /* Get evaluated modifier, so object links pointer to evaluated data,
+   * but still use original object it is applied to the original mesh. */
+  Object *ob_eval = DEG_get_evaluated_object(depsgraph, ob);
+  ModifierData *md_eval = (ob_eval) ? BKE_modifiers_findby_name(ob_eval, md->name) : md;
+
+  /* allow apply of a not-realtime modifier, by first re-enabling realtime. */
+  int prev_mode = md_eval->mode;
+  md_eval->mode |= eModifierMode_Realtime;
+
+  if (mode == MODIFIER_APPLY_SHAPE) {
+    if (!modifier_apply_shape(bmain, reports, depsgraph, scene, ob, md_eval)) {
+      md_eval->mode = prev_mode;
+      return false;
+    }
+  }
+  else {
+    if (!modifier_apply_obdata(reports, depsgraph, scene, ob, md_eval)) {
+      md_eval->mode = prev_mode;
+      return false;
+    }
+  }
+
+  md_eval->mode = prev_mode;
+
+  if (!keep_modifier) {
+    BKE_modifier_remove_from_list(ob, md);
+    BKE_modifier_free(md);
+  }
+
+  BKE_object_free_derived_caches(ob);
+
+  return true;
+}
+
+bool ED_object_modifier_copy(
+    ReportList *UNUSED(reports), Main *bmain, Scene *scene, Object *ob, ModifierData *md)
+{
+  if (md->type == eModifierType_ParticleSystem) {
+    ModifierData *nmd = object_copy_particle_system(
+        bmain, scene, ob, ((ParticleSystemModifierData *)md)->psys);
+    BLI_remlink(&ob->modifiers, nmd);
+    BLI_insertlinkafter(&ob->modifiers, md, nmd);
+    BKE_object_modifier_set_active(ob, nmd);
+    return true;
+  }
+
+  ModifierData *nmd = BKE_modifier_new(md->type);
+  BKE_modifier_copydata(md, nmd);
+  BLI_insertlinkafter(&ob->modifiers, md, nmd);
+  BKE_modifier_unique_name(&ob->modifiers, nmd);
+  BKE_object_modifier_set_active(ob, nmd);
+
+  nmd->flag |= eModifierFlag_OverrideLibrary_Local;
+
+  return true;
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Add Modifier Operator
+ * \{ */
+
+static int modifier_add_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Scene *scene = CTX_data_scene(C);
+  Object *ob = ED_object_active_context(C);
+  int type = RNA_enum_get(op->ptr, "type");
+
+  if (!ED_object_modifier_add(op->reports, bmain, scene, ob, nullptr, type)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static const EnumPropertyItem *modifier_add_itemf(bContext *C,
+                                                  PointerRNA *UNUSED(ptr),
+                                                  PropertyRNA *UNUSED(prop),
+                                                  bool *r_free)
+{
+  Object *ob = ED_object_active_context(C);
+
+  if (!ob) {
+    return rna_enum_object_modifier_type_items;
+  }
+
+  EnumPropertyItem *items = nullptr;
+  int totitem = 0;
+
+  const EnumPropertyItem *group_item = nullptr;
+  for (int a = 0; rna_enum_object_modifier_type_items[a].identifier; a++) {
+    const EnumPropertyItem *md_item = &rna_enum_object_modifier_type_items[a];
+
+    if (md_item->identifier[0]) {
+      const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md_item->value);
+
+      if (mti->flags & eModifierTypeFlag_NoUserAdd) {
+        continue;
+      }
+
+      if (!BKE_object_support_modifier_type_check(ob, md_item->value)) {
+        continue;
+      }
+    }
+    else {
+      group_item = md_item;
+      continue;
+    }
+
+    if (group_item) {
+      RNA_enum_item_add(&items, &totitem, group_item);
+      group_item = nullptr;
+    }
+
+    RNA_enum_item_add(&items, &totitem, md_item);
+  }
+
+  RNA_enum_item_end(&items, &totitem);
+  *r_free = true;
+
+  return items;
+}
+
+void OBJECT_OT_modifier_add(wmOperatorType *ot)
+{
+  PropertyRNA *prop;
+
+  /* identifiers */
+  ot->name = "Add Modifier";
+  ot->description = "Add a procedural operation/effect to the active object";
+  ot->idname = "OBJECT_OT_modifier_add";
+
+  /* api callbacks */
+  ot->invoke = WM_menu_invoke;
+  ot->exec = modifier_add_exec;
+  ot->poll = ED_operator_object_active_editable;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* properties */
+  prop = RNA_def_enum(
+      ot->srna, "type", rna_enum_object_modifier_type_items, eModifierType_Subsurf, "Type", "");
+  RNA_def_enum_funcs(prop, modifier_add_itemf);
+  ot->prop = prop;
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Generic Poll Function and Properties
+ *
+ * Using modifier names and data context.
+ * \{ */
+
+bool edit_modifier_poll_generic(bContext *C,
+                                StructRNA *rna_type,
+                                int obtype_flag,
+                                const bool is_editmode_allowed,
+                                const bool is_liboverride_allowed)
+{
+  Main *bmain = CTX_data_main(C);
+  PointerRNA ptr = CTX_data_pointer_get_type(C, "modifier", rna_type);
+  Object *ob = (ptr.owner_id) ? (Object *)ptr.owner_id : ED_object_active_context(C);
+  ModifierData *mod = static_cast<ModifierData *>(ptr.data); /* May be nullptr. */
+
+  if (mod == nullptr && ob != nullptr) {
+    mod = BKE_object_active_modifier(ob);
+  }
+
+  if (!ob || !BKE_id_is_editable(bmain, &ob->id)) {
+    return false;
+  }
+  if (obtype_flag && ((1 << ob->type) & obtype_flag) == 0) {
+    return false;
+  }
+  if (ptr.owner_id && !BKE_id_is_editable(bmain, ptr.owner_id)) {
+    return false;
+  }
+
+  if (!is_liboverride_allowed && BKE_modifier_is_nonlocal_in_liboverride(ob, mod)) {
+    CTX_wm_operator_poll_msg_set(
+        C, "Cannot edit modifiers coming from linked data in a library override");
+    return false;
+  }
+
+  if (!is_editmode_allowed && CTX_data_edit_object(C) != nullptr) {
+    CTX_wm_operator_poll_msg_set(C, "This modifier operation is not allowed from Edit mode");
+    return false;
+  }
+
+  return true;
+}
+
+static bool edit_modifier_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_Modifier, 0, true, false);
+}
+
+/* Used by operators performing actions allowed also on modifiers from the overridden linked object
+ * (not only from added 'local' ones). */
+static bool edit_modifier_liboverride_allowed_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_Modifier, 0, true, true);
+}
+
+void edit_modifier_properties(wmOperatorType *ot)
+{
+  PropertyRNA *prop = RNA_def_string(
+      ot->srna, "modifier", nullptr, MAX_NAME, "Modifier", "Name of the modifier to edit");
+  RNA_def_property_flag(prop, PROP_HIDDEN);
+}
+
+static void edit_modifier_report_property(wmOperatorType *ot)
+{
+  PropertyRNA *prop = RNA_def_boolean(
+      ot->srna, "report", false, "Report", "Create a notification after the operation");
+  RNA_def_property_flag(prop, PROP_HIDDEN);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Generic Invoke Functions
+ *
+ * Using modifier names and data context.
+ * \{ */
+
+bool edit_modifier_invoke_properties(bContext *C, wmOperator *op)
+{
+  if (RNA_struct_property_is_set(op->ptr, "modifier")) {
+    return true;
+  }
+
+  PointerRNA ctx_ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_Modifier);
+  if (ctx_ptr.data != nullptr) {
+    ModifierData *md = static_cast<ModifierData *>(ctx_ptr.data);
+    RNA_string_set(op->ptr, "modifier", md->name);
+    return true;
+  }
+
+  return false;
+}
+
+/**
+ * If the "modifier" property is not set, fill the modifier property with the name of the modifier
+ * with a UI panel below the mouse cursor, unless a specific modifier is set with a context
+ * pointer. Used in order to apply modifier operators on hover over their panels.
+ */
+static bool edit_modifier_invoke_properties_with_hover(bContext *C,
+                                                       wmOperator *op,
+                                                       const wmEvent *event,
+                                                       int *r_retval)
+{
+  if (RNA_struct_property_is_set(op->ptr, "modifier")) {
+    return true;
+  }
+
+  /* Note that the context pointer is *not* the active modifier, it is set in UI layouts. */
+  PointerRNA ctx_ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_Modifier);
+  if (ctx_ptr.data != nullptr) {
+    ModifierData *md = static_cast<ModifierData *>(ctx_ptr.data);
+    RNA_string_set(op->ptr, "modifier", md->name);
+    return true;
+  }
+
+  PointerRNA *panel_ptr = UI_region_panel_custom_data_under_cursor(C, event);
+  if (panel_ptr == nullptr || RNA_pointer_is_null(panel_ptr)) {
+    *r_retval = OPERATOR_CANCELLED;
+    return false;
+  }
+
+  if (!RNA_struct_is_a(panel_ptr->type, &RNA_Modifier)) {
+    /* Work around multiple operators using the same shortcut. The operators for the other
+     * stacks in the property editor use the same key, and will not run after these return
+     * OPERATOR_CANCELLED. */
+    *r_retval = (OPERATOR_PASS_THROUGH | OPERATOR_CANCELLED);
+    return false;
+  }
+
+  const ModifierData *md = static_cast<const ModifierData *>(panel_ptr->data);
+  RNA_string_set(op->ptr, "modifier", md->name);
+  return true;
+}
+
+ModifierData *edit_modifier_property_get(wmOperator *op, Object *ob, int type)
+{
+  char modifier_name[MAX_NAME];
+  RNA_string_get(op->ptr, "modifier", modifier_name);
+
+  ModifierData *md = BKE_modifiers_findby_name(ob, modifier_name);
+
+  if (md && type != 0 && md->type != type) {
+    md = nullptr;
+  }
+
+  return md;
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Remove Modifier Operator
+ * \{ */
+
+static int modifier_remove_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Scene *scene = CTX_data_scene(C);
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+  int mode_orig = ob->mode;
+
+  if (md == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  /* Store name temporarily for report. */
+  char name[MAX_NAME];
+  strcpy(name, md->name);
+
+  if (!ED_object_modifier_remove(op->reports, bmain, scene, ob, md)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  /* if cloth/softbody was removed, particle mode could be cleared */
+  if (mode_orig & OB_MODE_PARTICLE_EDIT) {
+    if ((ob->mode & OB_MODE_PARTICLE_EDIT) == 0) {
+      if (ob == OBACT(view_layer)) {
+        WM_event_add_notifier(C, NC_SCENE | ND_MODE | NS_MODE_OBJECT, nullptr);
+      }
+    }
+  }
+
+  if (RNA_boolean_get(op->ptr, "report")) {
+    BKE_reportf(op->reports, RPT_INFO, "Removed modifier: %s", name);
+  }
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_remove_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_remove_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_remove(wmOperatorType *ot)
+{
+  ot->name = "Remove Modifier";
+  ot->description = "Remove a modifier from the active object";
+  ot->idname = "OBJECT_OT_modifier_remove";
+
+  ot->invoke = modifier_remove_invoke;
+  ot->exec = modifier_remove_exec;
+  ot->poll = edit_modifier_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+  edit_modifier_report_property(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Move Up Modifier Operator
+ * \{ */
+
+static int modifier_move_up_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+
+  if (!md || !ED_object_modifier_move_up(op->reports, ob, md)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_move_up_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_move_up_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_move_up(wmOperatorType *ot)
+{
+  ot->name = "Move Up Modifier";
+  ot->description = "Move modifier up in the stack";
+  ot->idname = "OBJECT_OT_modifier_move_up";
+
+  ot->invoke = modifier_move_up_invoke;
+  ot->exec = modifier_move_up_exec;
+  ot->poll = edit_modifier_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Move Down Modifier Operator
+ * \{ */
+
+static int modifier_move_down_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+
+  if (!md || !ED_object_modifier_move_down(op->reports, ob, md)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_move_down_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_move_down_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_move_down(wmOperatorType *ot)
+{
+  ot->name = "Move Down Modifier";
+  ot->description = "Move modifier down in the stack";
+  ot->idname = "OBJECT_OT_modifier_move_down";
+
+  ot->invoke = modifier_move_down_invoke;
+  ot->exec = modifier_move_down_exec;
+  ot->poll = edit_modifier_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Move to Index Modifier Operator
+ * \{ */
+
+static int modifier_move_to_index_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+  int index = RNA_int_get(op->ptr, "index");
+
+  if (!ED_object_modifier_move_to_index(op->reports, ob, md, index)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_move_to_index_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_move_to_index_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_move_to_index(wmOperatorType *ot)
+{
+  ot->name = "Move Active Modifier to Index";
+  ot->description =
+      "Change the modifier's index in the stack so it evaluates after the set number of others";
+  ot->idname = "OBJECT_OT_modifier_move_to_index";
+
+  ot->invoke = modifier_move_to_index_invoke;
+  ot->exec = modifier_move_to_index_exec;
+  ot->poll = edit_modifier_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+  RNA_def_int(
+      ot->srna, "index", 0, 0, INT_MAX, "Index", "The index to move the modifier to", 0, INT_MAX);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Apply Modifier Operator
+ * \{ */
+
+static bool modifier_apply_poll(bContext *C)
+{
+  if (!edit_modifier_poll_generic(C, &RNA_Modifier, 0, false, false)) {
+    return false;
+  }
+
+  Scene *scene = CTX_data_scene(C);
+  PointerRNA ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_Modifier);
+  Object *ob = (ptr.owner_id != nullptr) ? (Object *)ptr.owner_id : ED_object_active_context(C);
+  ModifierData *md = static_cast<ModifierData *>(ptr.data); /* May be nullptr. */
+
+  if (ID_IS_OVERRIDE_LIBRARY(ob) || ((ob->data != nullptr) && ID_IS_OVERRIDE_LIBRARY(ob->data))) {
+    CTX_wm_operator_poll_msg_set(C, "Modifiers cannot be applied on override data");
+    return false;
+  }
+  if (md != nullptr) {
+    if ((ob->mode & OB_MODE_SCULPT) && (find_multires_modifier_before(scene, md)) &&
+        (BKE_modifier_is_same_topology(md) == false)) {
+      CTX_wm_operator_poll_msg_set(
+          C, "Constructive modifier cannot be applied to multi-res data in sculpt mode");
+      return false;
+    }
+  }
+  return true;
+}
+
+static int modifier_apply_exec_ex(bContext *C, wmOperator *op, int apply_as, bool keep_modifier)
+{
+  Main *bmain = CTX_data_main(C);
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Scene *scene = CTX_data_scene(C);
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+  const bool do_report = RNA_boolean_get(op->ptr, "report");
+  const bool do_single_user = RNA_boolean_get(op->ptr, "single_user");
+
+  if (md == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (do_single_user && ID_REAL_USERS(ob->data) > 1) {
+    ED_object_single_obdata_user(bmain, scene, ob);
+    BKE_main_id_newptr_and_tag_clear(bmain);
+    WM_event_add_notifier(C, NC_WINDOW, nullptr);
+    DEG_relations_tag_update(bmain);
+  }
+
+  int reports_len;
+  char name[MAX_NAME];
+  if (do_report) {
+    reports_len = BLI_listbase_count(&op->reports->list);
+    strcpy(name, md->name); /* Store name temporarily since the modifier is removed. */
+  }
+
+  if (!ED_object_modifier_apply(
+          bmain, op->reports, depsgraph, scene, ob, md, apply_as, keep_modifier)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  DEG_relations_tag_update(bmain);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  if (do_report) {
+    /* Only add this report if the operator didn't cause another one. The purpose here is
+     * to alert that something happened, and the previous report will do that anyway. */
+    if (BLI_listbase_count(&op->reports->list) == reports_len) {
+      BKE_reportf(op->reports, RPT_INFO, "Applied modifier: %s", name);
+    }
+  }
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_apply_exec(bContext *C, wmOperator *op)
+{
+  return modifier_apply_exec_ex(C, op, MODIFIER_APPLY_DATA, false);
+}
+
+static int modifier_apply_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    PointerRNA ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_Modifier);
+    Object *ob = (ptr.owner_id != nullptr) ? (Object *)ptr.owner_id : ED_object_active_context(C);
+
+    if ((ob->data != nullptr) && ID_REAL_USERS(ob->data) > 1) {
+      PropertyRNA *prop = RNA_struct_find_property(op->ptr, "single_user");
+      if (!RNA_property_is_set(op->ptr, prop)) {
+        RNA_property_boolean_set(op->ptr, prop, true);
+      }
+      if (RNA_property_boolean_get(op->ptr, prop)) {
+        return WM_operator_confirm_message(
+            C, op, "Make object data single-user and apply modifier");
+      }
+    }
+    return modifier_apply_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_apply(wmOperatorType *ot)
+{
+  ot->name = "Apply Modifier";
+  ot->description = "Apply modifier and remove from the stack";
+  ot->idname = "OBJECT_OT_modifier_apply";
+
+  ot->invoke = modifier_apply_invoke;
+  ot->exec = modifier_apply_exec;
+  ot->poll = modifier_apply_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+
+  edit_modifier_properties(ot);
+  edit_modifier_report_property(ot);
+
+  PropertyRNA *prop = RNA_def_boolean(ot->srna,
+                                      "single_user",
+                                      false,
+                                      "Make Data Single User",
+                                      "Make the object's data single user if needed");
+  RNA_def_property_flag(prop, (PropertyFlag)(PROP_HIDDEN | PROP_SKIP_SAVE));
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Apply Modifier As Shapekey Operator
+ * \{ */
+
+static bool modifier_apply_as_shapekey_poll(bContext *C)
+{
+  return modifier_apply_poll(C);
+}
+
+static int modifier_apply_as_shapekey_exec(bContext *C, wmOperator *op)
+{
+  bool keep = RNA_boolean_get(op->ptr, "keep_modifier");
+
+  return modifier_apply_exec_ex(C, op, MODIFIER_APPLY_SHAPE, keep);
+}
+
+static int modifier_apply_as_shapekey_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_apply_as_shapekey_exec(C, op);
+  }
+  return retval;
+}
+
+static char *modifier_apply_as_shapekey_get_description(struct bContext *UNUSED(C),
+                                                        struct wmOperatorType *UNUSED(op),
+                                                        struct PointerRNA *values)
+{
+  bool keep = RNA_boolean_get(values, "keep_modifier");
+
+  if (keep) {
+    return BLI_strdup(TIP_("Apply modifier as a new shapekey and keep it in the stack"));
+  }
+
+  return nullptr;
+}
+
+void OBJECT_OT_modifier_apply_as_shapekey(wmOperatorType *ot)
+{
+  ot->name = "Apply Modifier as Shape Key";
+  ot->description = "Apply modifier as a new shape key and remove from the stack";
+  ot->idname = "OBJECT_OT_modifier_apply_as_shapekey";
+
+  ot->invoke = modifier_apply_as_shapekey_invoke;
+  ot->exec = modifier_apply_as_shapekey_exec;
+  ot->poll = modifier_apply_as_shapekey_poll;
+  ot->get_description = modifier_apply_as_shapekey_get_description;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+
+  RNA_def_boolean(
+      ot->srna, "keep_modifier", false, "Keep Modifier", "Do not remove the modifier from stack");
+  edit_modifier_properties(ot);
+  edit_modifier_report_property(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Convert Modifier Operator
+ * \{ */
+
+static int modifier_convert_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+
+  if (!md || !ED_object_modifier_convert(op->reports, bmain, depsgraph, view_layer, ob, md)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_convert_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return modifier_convert_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_modifier_convert(wmOperatorType *ot)
+{
+  ot->name = "Convert Modifier";
+  ot->description = "Convert particles to a mesh object";
+  ot->idname = "OBJECT_OT_modifier_convert";
+
+  ot->invoke = modifier_convert_invoke;
+  ot->exec = modifier_convert_exec;
+  ot->poll = edit_modifier_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Copy Modifier Operator
+ * \{ */
+
+static int modifier_copy_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Scene *scene = CTX_data_scene(C);
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+
+  if (!md || !ED_object_modifier_copy(op->reports, bmain, scene, ob, md)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_copy_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_copy_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_copy(wmOperatorType *ot)
+{
+  ot->name = "Copy Modifier";
+  ot->description = "Duplicate modifier at the same position in the stack";
+  ot->idname = "OBJECT_OT_modifier_copy";
+
+  ot->invoke = modifier_copy_invoke;
+  ot->exec = modifier_copy_exec;
+  ot->poll = edit_modifier_liboverride_allowed_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Set Active Modifier Operator
+ * \{ */
+
+static int modifier_set_active_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, ob, 0);
+
+  /* If there is no modifier set for this operator, clear the active modifier field. */
+  BKE_object_modifier_set_active(ob, md);
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_set_active_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_set_active_exec(C, op);
+  }
+  return retval;
+}
+
+void OBJECT_OT_modifier_set_active(wmOperatorType *ot)
+{
+  ot->name = "Set Active Modifier";
+  ot->description = "Activate the modifier to use as the context";
+  ot->idname = "OBJECT_OT_modifier_set_active";
+
+  ot->invoke = modifier_set_active_invoke;
+  ot->exec = modifier_set_active_exec;
+  ot->poll = edit_modifier_liboverride_allowed_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Copy Modifier To Selected Operator
+ * \{ */
+
+static int modifier_copy_to_selected_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Scene *scene = CTX_data_scene(C);
+  Object *obact = ED_object_active_context(C);
+  ModifierData *md = edit_modifier_property_get(op, obact, 0);
+
+  if (!md) {
+    return OPERATOR_CANCELLED;
+  }
+
+  int num_copied = 0;
+  const ModifierTypeInfo *mti = BKE_modifier_get_info((ModifierType)md->type);
+
+  CTX_DATA_BEGIN (C, Object *, ob, selected_objects) {
+    if (ob == obact) {
+      continue;
+    }
+
+    /* Checked in #BKE_object_copy_modifier, but check here too so we can give a better message. */
+    if (!BKE_object_support_modifier_type_check(ob, md->type)) {
+      BKE_reportf(op->reports,
+                  RPT_WARNING,
+                  "Object '%s' does not support %s modifiers",
+                  ob->id.name + 2,
+                  mti->name);
+      continue;
+    }
+
+    if (mti->flags & eModifierTypeFlag_Single) {
+      if (BKE_modifiers_findby_type(ob, (ModifierType)md->type)) {
+        BKE_reportf(op->reports,
+                    RPT_WARNING,
+                    "Modifier can only be added once to object '%s'",
+                    ob->id.name + 2);
+        continue;
+      }
+    }
+
+    if (!BKE_object_copy_modifier(bmain, scene, ob, obact, md)) {
+      BKE_reportf(op->reports,
+                  RPT_ERROR,
+                  "Copying modifier '%s' to object '%s' failed",
+                  md->name,
+                  ob->id.name + 2);
+    }
+
+    num_copied++;
+    WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+    DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY | ID_RECALC_ANIMATION);
+  }
+  CTX_DATA_END;
+
+  if (num_copied > 0) {
+    DEG_relations_tag_update(bmain);
+  }
+  else {
+    BKE_reportf(op->reports, RPT_ERROR, "Modifier '%s' was not copied to any objects", md->name);
+    return OPERATOR_CANCELLED;
+  }
+
+  return OPERATOR_FINISHED;
+}
+
+static int modifier_copy_to_selected_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+  if (edit_modifier_invoke_properties_with_hover(C, op, event, &retval)) {
+    return modifier_copy_to_selected_exec(C, op);
+  }
+  return retval;
+}
+
+static bool modifier_copy_to_selected_poll(bContext *C)
+{
+  PointerRNA ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_Modifier);
+  Object *obact = (ptr.owner_id) ? (Object *)ptr.owner_id : ED_object_active_context(C);
+  ModifierData *md = static_cast<ModifierData *>(ptr.data);
+
+  /* This just mirrors the check in #BKE_object_copy_modifier,
+   * but there is no reasoning for it there. */
+  if (md && ELEM(md->type, eModifierType_Hook, eModifierType_Collision)) {
+    CTX_wm_operator_poll_msg_set(C, R"(Not supported for "Collision" or "Hook" modifiers)");
+    return false;
+  }
+
+  if (!obact) {
+    CTX_wm_operator_poll_msg_set(C, "No selected object is active");
+    return false;
+  }
+
+  if (!BKE_object_supports_modifiers(obact)) {
+    CTX_wm_operator_poll_msg_set(C, "Object type of source object is not supported");
+    return false;
+  }
+
+  /* This could have a performance impact in the worst case, where there are many objects selected
+   * and none of them pass either of the checks. But that should be uncommon, and this operator is
+   * only exposed in a drop-down menu anyway. */
+  bool found_supported_objects = false;
+  CTX_DATA_BEGIN (C, Object *, ob, selected_objects) {
+    if (ob == obact) {
+      continue;
+    }
+
+    if (!md && BKE_object_supports_modifiers(ob)) {
+      /* Skip type check if modifier could not be found ("modifier" context variable not set). */
+      found_supported_objects = true;
+      break;
+    }
+    if (BKE_object_support_modifier_type_check(ob, md->type)) {
+      found_supported_objects = true;
+      break;
+    }
+  }
+  CTX_DATA_END;
+
+  if (!found_supported_objects) {
+    CTX_wm_operator_poll_msg_set(C, "No supported objects were selected");
+    return false;
+  }
+  return true;
+}
+
+void OBJECT_OT_modifier_copy_to_selected(wmOperatorType *ot)
+{
+  ot->name = "Copy Modifier to Selected";
+  ot->description = "Copy the modifier from the active object to all selected objects";
+  ot->idname = "OBJECT_OT_modifier_copy_to_selected";
+
+  ot->invoke = modifier_copy_to_selected_invoke;
+  ot->exec = modifier_copy_to_selected_exec;
+  ot->poll = modifier_copy_to_selected_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Delete Higher Levels Operator
+ * \{ */
+
+static bool multires_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_MultiresModifier, (1 << OB_MESH), true, false);
+}
+
+static int multires_higher_levels_delete_exec(bContext *C, wmOperator *op)
+{
+  Scene *scene = CTX_data_scene(C);
+  Object *ob = ED_object_active_context(C);
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  multiresModifier_del_levels(mmd, scene, ob, 1);
+
+  ED_object_iter_other(
+      CTX_data_main(C), ob, true, ED_object_multires_update_totlevels_cb, &mmd->totlvl);
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_higher_levels_delete_invoke(bContext *C,
+                                                wmOperator *op,
+                                                const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_higher_levels_delete_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_higher_levels_delete(wmOperatorType *ot)
+{
+  ot->name = "Delete Higher Levels";
+  ot->description = "Deletes the higher resolution mesh, potential loss of detail";
+  ot->idname = "OBJECT_OT_multires_higher_levels_delete";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_higher_levels_delete_invoke;
+  ot->exec = multires_higher_levels_delete_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Subdivide Operator
+ * \{ */
+
+static EnumPropertyItem prop_multires_subdivide_mode_type[] = {
+    {MULTIRES_SUBDIVIDE_CATMULL_CLARK,
+     "CATMULL_CLARK",
+     0,
+     "Catmull-Clark",
+     "Create a new level using Catmull-Clark subdivisions"},
+    {MULTIRES_SUBDIVIDE_SIMPLE,
+     "SIMPLE",
+     0,
+     "Simple",
+     "Create a new level using simple subdivisions"},
+    {MULTIRES_SUBDIVIDE_LINEAR,
+     "LINEAR",
+     0,
+     "Linear",
+     "Create a new level using linear interpolation of the sculpted displacement"},
+    {0, nullptr, 0, nullptr, nullptr},
+};
+
+static int multires_subdivide_exec(bContext *C, wmOperator *op)
+{
+  Object *object = ED_object_active_context(C);
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, object, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  const eMultiresSubdivideModeType subdivide_mode = (eMultiresSubdivideModeType)(RNA_enum_get(
+      op->ptr, "mode"));
+  multiresModifier_subdivide(object, mmd, subdivide_mode);
+
+  ED_object_iter_other(
+      CTX_data_main(C), object, true, ED_object_multires_update_totlevels_cb, &mmd->totlvl);
+
+  DEG_id_tag_update(&object->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, object);
+
+  if (object->mode & OB_MODE_SCULPT) {
+    /* ensure that grid paint mask layer is created */
+    BKE_sculpt_mask_layers_ensure(object, mmd);
+  }
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_subdivide_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_subdivide_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_subdivide(wmOperatorType *ot)
+{
+  ot->name = "Multires Subdivide";
+  ot->description = "Add a new level of subdivision";
+  ot->idname = "OBJECT_OT_multires_subdivide";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_subdivide_invoke;
+  ot->exec = multires_subdivide_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+  RNA_def_enum(ot->srna,
+               "mode",
+               prop_multires_subdivide_mode_type,
+               MULTIRES_SUBDIVIDE_CATMULL_CLARK,
+               "Subdivision Mode",
+               "How the mesh is going to be subdivided to create a new level");
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Reshape Operator
+ * \{ */
+
+static int multires_reshape_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Object *ob = ED_object_active_context(C), *secondob = nullptr;
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (mmd->lvl == 0) {
+    BKE_report(op->reports, RPT_ERROR, "Reshape can work only with higher levels of subdivisions");
+    return OPERATOR_CANCELLED;
+  }
+
+  CTX_DATA_BEGIN (C, Object *, selob, selected_editable_objects) {
+    if (selob->type == OB_MESH && selob != ob) {
+      secondob = selob;
+      break;
+    }
+  }
+  CTX_DATA_END;
+
+  if (!secondob) {
+    BKE_report(op->reports, RPT_ERROR, "Second selected mesh object required to copy shape from");
+    return OPERATOR_CANCELLED;
+  }
+
+  if (!multiresModifier_reshapeFromObject(depsgraph, mmd, ob, secondob)) {
+    BKE_report(op->reports, RPT_ERROR, "Objects do not have the same number of vertices");
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_reshape_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_reshape_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_reshape(wmOperatorType *ot)
+{
+  ot->name = "Multires Reshape";
+  ot->description = "Copy vertex coordinates from other object";
+  ot->idname = "OBJECT_OT_multires_reshape";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_reshape_invoke;
+  ot->exec = multires_reshape_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Save External Operator
+ * \{ */
+
+static int multires_external_save_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Object *ob = ED_object_active_context(C);
+  Mesh *me = (ob) ? static_cast<Mesh *>(ob->data) : static_cast<Mesh *>(op->customdata);
+  char path[FILE_MAX];
+  const bool relative = RNA_boolean_get(op->ptr, "relative_path");
+
+  if (!me) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (CustomData_external_test(&me->ldata, CD_MDISPS)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  RNA_string_get(op->ptr, "filepath", path);
+
+  if (relative) {
+    BLI_path_rel(path, BKE_main_blendfile_path(bmain));
+  }
+
+  CustomData_external_add(&me->ldata, &me->id, CD_MDISPS, me->totloop, path);
+  CustomData_external_write(&me->ldata, &me->id, CD_MASK_MESH.lmask, me->totloop, 0);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_external_save_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  Object *ob = ED_object_active_context(C);
+  Mesh *me = static_cast<Mesh *>(ob->data);
+  char path[FILE_MAX];
+
+  if (!edit_modifier_invoke_properties(C, op)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (CustomData_external_test(&me->ldata, CD_MDISPS)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (RNA_struct_property_is_set(op->ptr, "filepath")) {
+    return multires_external_save_exec(C, op);
+  }
+
+  op->customdata = me;
+
+  BLI_snprintf(path, sizeof(path), "//%s.btx", me->id.name + 2);
+  RNA_string_set(op->ptr, "filepath", path);
+
+  WM_event_add_fileselect(C, op);
+
+  return OPERATOR_RUNNING_MODAL;
+}
+
+void OBJECT_OT_multires_external_save(wmOperatorType *ot)
+{
+  ot->name = "Multires Save External";
+  ot->description = "Save displacements to an external file";
+  ot->idname = "OBJECT_OT_multires_external_save";
+
+  /* XXX modifier no longer in context after file browser .. ot->poll = multires_poll; */
+  ot->exec = multires_external_save_exec;
+  ot->invoke = multires_external_save_invoke;
+  ot->poll = multires_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+
+  WM_operator_properties_filesel(ot,
+                                 FILE_TYPE_FOLDER | FILE_TYPE_BTX,
+                                 FILE_SPECIAL,
+                                 FILE_SAVE,
+                                 WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH,
+                                 FILE_DEFAULTDISPLAY,
+                                 FILE_SORT_DEFAULT);
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Pack Operator
+ * \{ */
+
+static int multires_external_pack_exec(bContext *C, wmOperator *UNUSED(op))
+{
+  Object *ob = ED_object_active_context(C);
+  Mesh *me = static_cast<Mesh *>(ob->data);
+
+  if (!CustomData_external_test(&me->ldata, CD_MDISPS)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  /* XXX don't remove. */
+  CustomData_external_remove(&me->ldata, &me->id, CD_MDISPS, me->totloop);
+
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_multires_external_pack(wmOperatorType *ot)
+{
+  ot->name = "Multires Pack External";
+  ot->description = "Pack displacements from an external file";
+  ot->idname = "OBJECT_OT_multires_external_pack";
+
+  ot->poll = multires_poll;
+  ot->exec = multires_external_pack_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Apply Base
+ * \{ */
+
+static int multires_base_apply_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  Object *object = ED_object_active_context(C);
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, object, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  ED_sculpt_undo_push_multires_mesh_begin(C, op->type->name);
+
+  multiresModifier_base_apply(depsgraph, object, mmd);
+
+  ED_sculpt_undo_push_multires_mesh_end(C, op->type->name);
+
+  DEG_id_tag_update(&object->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, object);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_base_apply_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_base_apply_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_base_apply(wmOperatorType *ot)
+{
+  ot->name = "Multires Apply Base";
+  ot->description = "Modify the base mesh to conform to the displaced mesh";
+  ot->idname = "OBJECT_OT_multires_base_apply";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_base_apply_invoke;
+  ot->exec = multires_base_apply_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Unsubdivide
+ * \{ */
+
+static int multires_unsubdivide_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  Object *object = ED_object_active_context(C);
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, object, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  int new_levels = multiresModifier_rebuild_subdiv(depsgraph, object, mmd, 1, true);
+  if (new_levels == 0) {
+    BKE_report(op->reports, RPT_ERROR, "No valid subdivisions found to rebuild a lower level");
+    return OPERATOR_CANCELLED;
+  }
+
+  DEG_id_tag_update(&object->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, object);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_unsubdivide_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_unsubdivide_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_unsubdivide(wmOperatorType *ot)
+{
+  ot->name = "Unsubdivide";
+  ot->description = "Rebuild a lower subdivision level of the current base mesh";
+  ot->idname = "OBJECT_OT_multires_unsubdivide";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_unsubdivide_invoke;
+  ot->exec = multires_unsubdivide_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Multires Rebuild Subdivisions
+ * \{ */
+
+static int multires_rebuild_subdiv_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  Object *object = ED_object_active_context(C);
+  MultiresModifierData *mmd = (MultiresModifierData *)edit_modifier_property_get(
+      op, object, eModifierType_Multires);
+
+  if (!mmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  int new_levels = multiresModifier_rebuild_subdiv(depsgraph, object, mmd, INT_MAX, false);
+  if (new_levels == 0) {
+    BKE_report(op->reports, RPT_ERROR, "Not valid subdivisions found to rebuild lower levels");
+    return OPERATOR_CANCELLED;
+  }
+
+  BKE_reportf(op->reports, RPT_INFO, "%d new levels rebuilt", new_levels);
+
+  DEG_id_tag_update(&object->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, object);
+
+  return OPERATOR_FINISHED;
+}
+
+static int multires_rebuild_subdiv_invoke(bContext *C,
+                                          wmOperator *op,
+                                          const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return multires_rebuild_subdiv_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_multires_rebuild_subdiv(wmOperatorType *ot)
+{
+  ot->name = "Rebuild Lower Subdivisions";
+  ot->description =
+      "Rebuilds all possible subdivisions levels to generate a lower resolution base mesh";
+  ot->idname = "OBJECT_OT_multires_rebuild_subdiv";
+
+  ot->poll = multires_poll;
+  ot->invoke = multires_rebuild_subdiv_invoke;
+  ot->exec = multires_rebuild_subdiv_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Skin Modifier
+ * \{ */
+
+static void modifier_skin_customdata_delete(Object *ob)
+{
+  Mesh *me = static_cast<Mesh *>(ob->data);
+  BMEditMesh *em = me->edit_mesh;
+
+  if (em) {
+    BM_data_layer_free(em->bm, &em->bm->vdata, CD_MVERT_SKIN);
+  }
+  else {
+    CustomData_free_layer_active(&me->vdata, CD_MVERT_SKIN, me->totvert);
+  }
+}
+
+static bool skin_poll(bContext *C)
+{
+  return (edit_modifier_poll_generic(C, &RNA_SkinModifier, (1 << OB_MESH), false, false));
+}
+
+static bool skin_edit_poll(bContext *C)
+{
+  Object *ob = CTX_data_edit_object(C);
+  return (ob != nullptr &&
+          edit_modifier_poll_generic(C, &RNA_SkinModifier, (1 << OB_MESH), true, false) &&
+          !ID_IS_OVERRIDE_LIBRARY(ob) && !ID_IS_OVERRIDE_LIBRARY(ob->data));
+}
+
+static void skin_root_clear(BMVert *bm_vert, GSet *visited, const int cd_vert_skin_offset)
+{
+  BMEdge *bm_edge;
+  BMIter bm_iter;
+
+  BM_ITER_ELEM (bm_edge, &bm_iter, bm_vert, BM_EDGES_OF_VERT) {
+    BMVert *v2 = BM_edge_other_vert(bm_edge, bm_vert);
+
+    if (BLI_gset_add(visited, v2)) {
+      MVertSkin *vs = static_cast<MVertSkin *>(BM_ELEM_CD_GET_VOID_P(v2, cd_vert_skin_offset));
+
+      /* clear vertex root flag and add to visited set */
+      vs->flag &= ~MVERT_SKIN_ROOT;
+
+      skin_root_clear(v2, visited, cd_vert_skin_offset);
+    }
+  }
+}
+
+static int skin_root_mark_exec(bContext *C, wmOperator *UNUSED(op))
+{
+  Object *ob = CTX_data_edit_object(C);
+  BMEditMesh *em = BKE_editmesh_from_object(ob);
+  BMesh *bm = em->bm;
+
+  GSet *visited = BLI_gset_ptr_new(__func__);
+
+  BKE_mesh_ensure_skin_customdata(static_cast<Mesh *>(ob->data));
+
+  const int cd_vert_skin_offset = CustomData_get_offset(&bm->vdata, CD_MVERT_SKIN);
+
+  BMVert *bm_vert;
+  BMIter bm_iter;
+  BM_ITER_MESH (bm_vert, &bm_iter, bm, BM_VERTS_OF_MESH) {
+    if (BM_elem_flag_test(bm_vert, BM_ELEM_SELECT) && BLI_gset_add(visited, bm_vert)) {
+      MVertSkin *vs = static_cast<MVertSkin *>(
+          BM_ELEM_CD_GET_VOID_P(bm_vert, cd_vert_skin_offset));
+
+      /* mark vertex as root and add to visited set */
+      vs->flag |= MVERT_SKIN_ROOT;
+
+      /* clear root flag from all connected vertices (recursively) */
+      skin_root_clear(bm_vert, visited, cd_vert_skin_offset);
+    }
+  }
+
+  BLI_gset_free(visited, nullptr);
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_skin_root_mark(wmOperatorType *ot)
+{
+  ot->name = "Skin Root Mark";
+  ot->description = "Mark selected vertices as roots";
+  ot->idname = "OBJECT_OT_skin_root_mark";
+
+  ot->poll = skin_edit_poll;
+  ot->exec = skin_root_mark_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+enum SkinLooseAction {
+  SKIN_LOOSE_MARK,
+  SKIN_LOOSE_CLEAR,
+};
+
+static int skin_loose_mark_clear_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = CTX_data_edit_object(C);
+  BMEditMesh *em = BKE_editmesh_from_object(ob);
+  BMesh *bm = em->bm;
+  SkinLooseAction action = static_cast<SkinLooseAction>(RNA_enum_get(op->ptr, "action"));
+
+  if (!CustomData_has_layer(&bm->vdata, CD_MVERT_SKIN)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  BMVert *bm_vert;
+  BMIter bm_iter;
+  BM_ITER_MESH (bm_vert, &bm_iter, bm, BM_VERTS_OF_MESH) {
+    if (BM_elem_flag_test(bm_vert, BM_ELEM_SELECT)) {
+      MVertSkin *vs = static_cast<MVertSkin *>(
+          CustomData_bmesh_get(&bm->vdata, bm_vert->head.data, CD_MVERT_SKIN));
+
+      switch (action) {
+        case SKIN_LOOSE_MARK:
+          vs->flag |= MVERT_SKIN_LOOSE;
+          break;
+        case SKIN_LOOSE_CLEAR:
+          vs->flag &= ~MVERT_SKIN_LOOSE;
+          break;
+      }
+    }
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_skin_loose_mark_clear(wmOperatorType *ot)
+{
+  static const EnumPropertyItem action_items[] = {
+      {SKIN_LOOSE_MARK, "MARK", 0, "Mark", "Mark selected vertices as loose"},
+      {SKIN_LOOSE_CLEAR, "CLEAR", 0, "Clear", "Set selected vertices as not loose"},
+      {0, nullptr, 0, nullptr, nullptr},
+  };
+
+  ot->name = "Skin Mark/Clear Loose";
+  ot->description = "Mark/clear selected vertices as loose";
+  ot->idname = "OBJECT_OT_skin_loose_mark_clear";
+
+  ot->poll = skin_edit_poll;
+  ot->exec = skin_loose_mark_clear_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  RNA_def_enum(ot->srna, "action", action_items, SKIN_LOOSE_MARK, "Action", nullptr);
+}
+
+static int skin_radii_equalize_exec(bContext *C, wmOperator *UNUSED(op))
+{
+  Object *ob = CTX_data_edit_object(C);
+  BMEditMesh *em = BKE_editmesh_from_object(ob);
+  BMesh *bm = em->bm;
+
+  if (!CustomData_has_layer(&bm->vdata, CD_MVERT_SKIN)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  BMVert *bm_vert;
+  BMIter bm_iter;
+  BM_ITER_MESH (bm_vert, &bm_iter, bm, BM_VERTS_OF_MESH) {
+    if (BM_elem_flag_test(bm_vert, BM_ELEM_SELECT)) {
+      MVertSkin *vs = static_cast<MVertSkin *>(
+          CustomData_bmesh_get(&bm->vdata, bm_vert->head.data, CD_MVERT_SKIN));
+      float avg = (vs->radius[0] + vs->radius[1]) * 0.5f;
+
+      vs->radius[0] = vs->radius[1] = avg;
+    }
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_skin_radii_equalize(wmOperatorType *ot)
+{
+  ot->name = "Skin Radii Equalize";
+  ot->description = "Make skin radii of selected vertices equal on each axis";
+  ot->idname = "OBJECT_OT_skin_radii_equalize";
+
+  ot->poll = skin_edit_poll;
+  ot->exec = skin_radii_equalize_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+static void skin_armature_bone_create(Object *skin_ob,
+                                      MVert *mvert,
+                                      MEdge *medge,
+                                      bArmature *arm,
+                                      BLI_bitmap *edges_visited,
+                                      const MeshElemMap *emap,
+                                      EditBone *parent_bone,
+                                      int parent_v)
+{
+  for (int i = 0; i < emap[parent_v].count; i++) {
+    int endx = emap[parent_v].indices[i];
+    const MEdge *e = &medge[endx];
+
+    /* ignore edge if already visited */
+    if (BLI_BITMAP_TEST(edges_visited, endx)) {
+      continue;
+    }
+    BLI_BITMAP_ENABLE(edges_visited, endx);
+
+    int v = (e->v1 == parent_v ? e->v2 : e->v1);
+
+    EditBone *bone = ED_armature_ebone_add(arm, "Bone");
+
+    bone->parent = parent_bone;
+    if (parent_bone != nullptr) {
+      bone->flag |= BONE_CONNECTED;
+    }
+
+    copy_v3_v3(bone->head, mvert[parent_v].co);
+    copy_v3_v3(bone->tail, mvert[v].co);
+    bone->rad_head = bone->rad_tail = 0.25;
+    BLI_snprintf(bone->name, sizeof(bone->name), "Bone.%.2d", endx);
+
+    /* add bDeformGroup */
+    bDeformGroup *dg = BKE_object_defgroup_add_name(skin_ob, bone->name);
+    if (dg != nullptr) {
+      ED_vgroup_vert_add(skin_ob, dg, parent_v, 1, WEIGHT_REPLACE);
+      ED_vgroup_vert_add(skin_ob, dg, v, 1, WEIGHT_REPLACE);
+    }
+
+    skin_armature_bone_create(skin_ob, mvert, medge, arm, edges_visited, emap, bone, v);
+  }
+}
+
+static Object *modifier_skin_armature_create(Depsgraph *depsgraph, Main *bmain, Object *skin_ob)
+{
+  Mesh *me = static_cast<Mesh *>(skin_ob->data);
+
+  Scene *scene_eval = DEG_get_evaluated_scene(depsgraph);
+  Object *ob_eval = DEG_get_evaluated_object(depsgraph, skin_ob);
+
+  Mesh *me_eval_deform = mesh_get_eval_deform(depsgraph, scene_eval, ob_eval, &CD_MASK_BAREMESH);
+  MVert *mvert = me_eval_deform->mvert;
+
+  /* add vertex weights to original mesh */
+  CustomData_add_layer(&me->vdata, CD_MDEFORMVERT, CD_CALLOC, nullptr, me->totvert);
+
+  ViewLayer *view_layer = DEG_get_input_view_layer(depsgraph);
+  Object *arm_ob = BKE_object_add(bmain, view_layer, OB_ARMATURE, nullptr);
+  BKE_object_transform_copy(arm_ob, skin_ob);
+  bArmature *arm = static_cast<bArmature *>(arm_ob->data);
+  arm->layer = 1;
+  arm_ob->dtx |= OB_DRAW_IN_FRONT;
+  arm->drawtype = ARM_LINE;
+  arm->edbo = MEM_cnew<ListBase>("edbo armature");
+
+  MVertSkin *mvert_skin = static_cast<MVertSkin *>(
+      CustomData_get_layer(&me->vdata, CD_MVERT_SKIN));
+  int *emap_mem;
+  MeshElemMap *emap;
+  BKE_mesh_vert_edge_map_create(&emap, &emap_mem, me->medge, me->totvert, me->totedge);
+
+  BLI_bitmap *edges_visited = BLI_BITMAP_NEW(me->totedge, "edge_visited");
+
+  /* NOTE: we use EditBones here, easier to set them up and use
+   * edit-armature functions to convert back to regular bones */
+  for (int v = 0; v < me->totvert; v++) {
+    if (mvert_skin[v].flag & MVERT_SKIN_ROOT) {
+      EditBone *bone = nullptr;
+
+      /* Unless the skin root has just one adjacent edge, create
+       * a fake root bone (have it going off in the Y direction
+       * (arbitrary) */
+      if (emap[v].count > 1) {
+        bone = ED_armature_ebone_add(arm, "Bone");
+
+        copy_v3_v3(bone->head, me->mvert[v].co);
+        copy_v3_v3(bone->tail, me->mvert[v].co);
+
+        bone->head[1] = 1.0f;
+        bone->rad_head = bone->rad_tail = 0.25;
+      }
+
+      if (emap[v].count >= 1) {
+        skin_armature_bone_create(skin_ob, mvert, me->medge, arm, edges_visited, emap, bone, v);
+      }
+    }
+  }
+
+  MEM_freeN(edges_visited);
+  MEM_freeN(emap);
+  MEM_freeN(emap_mem);
+
+  ED_armature_from_edit(bmain, arm);
+  ED_armature_edit_free(arm);
+
+  return arm_ob;
+}
+
+static int skin_armature_create_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Object *ob = CTX_data_active_object(C);
+  Mesh *me = static_cast<Mesh *>(ob->data);
+  ModifierData *skin_md;
+
+  if (!CustomData_has_layer(&me->vdata, CD_MVERT_SKIN)) {
+    BKE_reportf(op->reports, RPT_WARNING, "Mesh '%s' has no skin vertex data", me->id.name + 2);
+    return OPERATOR_CANCELLED;
+  }
+
+  /* create new armature */
+  Object *arm_ob = modifier_skin_armature_create(depsgraph, bmain, ob);
+
+  /* add a modifier to connect the new armature to the mesh */
+  ArmatureModifierData *arm_md = (ArmatureModifierData *)BKE_modifier_new(eModifierType_Armature);
+  if (arm_md) {
+    skin_md = edit_modifier_property_get(op, ob, eModifierType_Skin);
+    BLI_insertlinkafter(&ob->modifiers, skin_md, arm_md);
+
+    arm_md->object = arm_ob;
+    arm_md->deformflag = ARM_DEF_VGROUP | ARM_DEF_QUATERNION;
+    DEG_relations_tag_update(bmain);
+    DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  }
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int skin_armature_create_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return skin_armature_create_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_skin_armature_create(wmOperatorType *ot)
+{
+  ot->name = "Skin Armature Create";
+  ot->description = "Create an armature that parallels the skin layout";
+  ot->idname = "OBJECT_OT_skin_armature_create";
+
+  ot->poll = skin_poll;
+  ot->invoke = skin_armature_create_invoke;
+  ot->exec = skin_armature_create_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Delta Mesh Bind Operator
+ * \{ */
+
+static bool correctivesmooth_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_CorrectiveSmoothModifier, 0, true, false);
+}
+
+static int correctivesmooth_bind_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Scene *scene = CTX_data_scene(C);
+  Object *ob = ED_object_active_context(C);
+  CorrectiveSmoothModifierData *csmd = (CorrectiveSmoothModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_CorrectiveSmooth);
+
+  if (!csmd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (!BKE_modifier_is_enabled(scene, &csmd->modifier, eModifierMode_Realtime)) {
+    BKE_report(op->reports, RPT_ERROR, "Modifier is disabled");
+    return OPERATOR_CANCELLED;
+  }
+
+  const bool is_bind = (csmd->bind_coords != nullptr);
+
+  MEM_SAFE_FREE(csmd->bind_coords);
+  MEM_SAFE_FREE(csmd->delta_cache.deltas);
+
+  if (is_bind) {
+    /* toggle off */
+    csmd->bind_coords_num = 0;
+  }
+  else {
+    /* Signal to modifier to recalculate. */
+    CorrectiveSmoothModifierData *csmd_eval = (CorrectiveSmoothModifierData *)
+        BKE_modifier_get_evaluated(depsgraph, ob, &csmd->modifier);
+    csmd_eval->bind_coords_num = (uint)-1;
+
+    /* Force modifier to run, it will call binding routine
+     * (this has to happen outside of depsgraph evaluation). */
+    object_force_modifier_bind_simple_options(depsgraph, ob, &csmd->modifier);
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int correctivesmooth_bind_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return correctivesmooth_bind_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_correctivesmooth_bind(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Corrective Smooth Bind";
+  ot->description = "Bind base pose in Corrective Smooth modifier";
+  ot->idname = "OBJECT_OT_correctivesmooth_bind";
+
+  /* api callbacks */
+  ot->poll = correctivesmooth_poll;
+  ot->invoke = correctivesmooth_bind_invoke;
+  ot->exec = correctivesmooth_bind_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Mesh Deform Bind Operator
+ * \{ */
+
+static bool meshdeform_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_MeshDeformModifier, 0, true, false);
+}
+
+static int meshdeform_bind_exec(bContext *C, wmOperator *op)
+{
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Object *ob = ED_object_active_context(C);
+  MeshDeformModifierData *mmd = (MeshDeformModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_MeshDeform);
+
+  if (mmd == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (mmd->bindcagecos != nullptr) {
+    MEM_SAFE_FREE(mmd->bindcagecos);
+    MEM_SAFE_FREE(mmd->dyngrid);
+    MEM_SAFE_FREE(mmd->dyninfluences);
+    MEM_SAFE_FREE(mmd->bindinfluences);
+    MEM_SAFE_FREE(mmd->bindoffsets);
+    MEM_SAFE_FREE(mmd->dynverts);
+    MEM_SAFE_FREE(mmd->bindweights); /* Deprecated */
+    MEM_SAFE_FREE(mmd->bindcos);     /* Deprecated */
+    mmd->verts_num = 0;
+    mmd->cage_verts_num = 0;
+    mmd->influences_num = 0;
+  }
+  else {
+    /* Force modifier to run, it will call binding routine
+     * (this has to happen outside of depsgraph evaluation). */
+    MeshDeformModifierData *mmd_eval = (MeshDeformModifierData *)BKE_modifier_get_evaluated(
+        depsgraph, ob, &mmd->modifier);
+    mmd_eval->bindfunc = ED_mesh_deform_bind_callback;
+    object_force_modifier_bind_simple_options(depsgraph, ob, &mmd->modifier);
+    mmd_eval->bindfunc = nullptr;
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+  return OPERATOR_FINISHED;
+}
+
+static int meshdeform_bind_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return meshdeform_bind_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_meshdeform_bind(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Mesh Deform Bind";
+  ot->description = "Bind mesh to cage in mesh deform modifier";
+  ot->idname = "OBJECT_OT_meshdeform_bind";
+
+  /* api callbacks */
+  ot->poll = meshdeform_poll;
+  ot->invoke = meshdeform_bind_invoke;
+  ot->exec = meshdeform_bind_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Explode Refresh Operator
+ * \{ */
+
+static bool explode_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_ExplodeModifier, 0, true, false);
+}
+
+static int explode_refresh_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  ExplodeModifierData *emd = (ExplodeModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_Explode);
+
+  if (!emd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  emd->flag |= eExplodeFlag_CalcFaces;
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+static int explode_refresh_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return explode_refresh_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_explode_refresh(wmOperatorType *ot)
+{
+  ot->name = "Explode Refresh";
+  ot->description = "Refresh data in the Explode modifier";
+  ot->idname = "OBJECT_OT_explode_refresh";
+
+  ot->poll = explode_poll;
+  ot->invoke = explode_refresh_invoke;
+  ot->exec = explode_refresh_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Ocean Bake Operator
+ * \{ */
+
+static bool ocean_bake_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_OceanModifier, 0, true, false);
+}
+
+struct OceanBakeJob {
+  /* from wmJob */
+  struct Object *owner;
+  short *stop, *do_update;
+  float *progress;
+  int current_frame;
+  struct OceanCache *och;
+  struct Ocean *ocean;
+  struct OceanModifierData *omd;
+};
+
+static void oceanbake_free(void *customdata)
+{
+  OceanBakeJob *oj = static_cast<OceanBakeJob *>(customdata);
+  MEM_delete(oj);
+}
+
+/* called by oceanbake, only to check job 'stop' value */
+static int oceanbake_breakjob(void *UNUSED(customdata))
+{
+  // OceanBakeJob *ob = (OceanBakeJob *)customdata;
+  // return *(ob->stop);
+
+  /* this is not nice yet, need to make the jobs list template better
+   * for identifying/acting upon various different jobs */
+  /* but for now we'll reuse the render break... */
+  return (G.is_break);
+}
+
+/* called by oceanbake, wmJob sends notifier */
+static void oceanbake_update(void *customdata, float progress, int *cancel)
+{
+  OceanBakeJob *oj = static_cast<OceanBakeJob *>(customdata);
+
+  if (oceanbake_breakjob(oj)) {
+    *cancel = 1;
+  }
+
+  *(oj->do_update) = true;
+  *(oj->progress) = progress;
+}
+
+static void oceanbake_startjob(void *customdata, short *stop, short *do_update, float *progress)
+{
+  OceanBakeJob *oj = static_cast<OceanBakeJob *>(customdata);
+
+  oj->stop = stop;
+  oj->do_update = do_update;
+  oj->progress = progress;
+
+  G.is_break = false; /* XXX shared with render - replace with job 'stop' switch */
+
+  BKE_ocean_bake(oj->ocean, oj->och, oceanbake_update, (void *)oj);
+
+  *do_update = true;
+  *stop = 0;
+}
+
+static void oceanbake_endjob(void *customdata)
+{
+  OceanBakeJob *oj = static_cast<OceanBakeJob *>(customdata);
+
+  if (oj->ocean) {
+    BKE_ocean_free(oj->ocean);
+    oj->ocean = nullptr;
+  }
+
+  oj->omd->oceancache = oj->och;
+  oj->omd->cached = true;
+
+  Object *ob = oj->owner;
+  DEG_id_tag_update(&ob->id, ID_RECALC_COPY_ON_WRITE);
+}
+
+static int ocean_bake_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Object *ob = ED_object_active_context(C);
+  OceanModifierData *omd = (OceanModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_Ocean);
+  Scene *scene = CTX_data_scene(C);
+  const bool free = RNA_boolean_get(op->ptr, "free");
+
+  if (!omd) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (free) {
+    BKE_ocean_free_modifier_cache(omd);
+    DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+    WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+    return OPERATOR_FINISHED;
+  }
+
+  OceanCache *och = BKE_ocean_init_cache(omd->cachepath,
+                                         BKE_modifier_path_relbase(bmain, ob),
+                                         omd->bakestart,
+                                         omd->bakeend,
+                                         omd->wave_scale,
+                                         omd->chop_amount,
+                                         omd->foam_coverage,
+                                         omd->foam_fade,
+                                         omd->resolution);
+
+  och->time = static_cast<float *>(MEM_mallocN(och->duration * sizeof(float), "foam bake time"));
+
+  int cfra = scene->r.cfra;
+
+  /* precalculate time variable before baking */
+  int i = 0;
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  for (int f = omd->bakestart; f <= omd->bakeend; f++) {
+    /* For now only simple animation of time value is supported, nothing else.
+     * No drivers or other modifier parameters. */
+    /* TODO(sergey): This operates on an original data, so no flush is needed. However, baking
+     * usually should happen on an evaluated objects, so this seems to be deeper issue here. */
+
+    const AnimationEvalContext anim_eval_context = BKE_animsys_eval_context_construct(depsgraph,
+                                                                                      f);
+    BKE_animsys_evaluate_animdata((ID *)ob, ob->adt, &anim_eval_context, ADT_RECALC_ANIM, false);
+
+    och->time[i] = omd->time;
+    i++;
+  }
+
+  /* Make a copy of ocean to use for baking - thread-safety. */
+  struct Ocean *ocean = BKE_ocean_add();
+  BKE_ocean_init_from_modifier(ocean, omd, omd->resolution);
+
+#if 0
+  BKE_ocean_bake(ocean, och);
+
+  omd->oceancache = och;
+  omd->cached = true;
+
+  scene->r.cfra = cfra;
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+#endif
+
+  /* job stuff */
+
+  scene->r.cfra = cfra;
+
+  /* setup job */
+  wmJob *wm_job = WM_jobs_get(CTX_wm_manager(C),
+                              CTX_wm_window(C),
+                              scene,
+                              "Ocean Simulation",
+                              WM_JOB_PROGRESS,
+                              WM_JOB_TYPE_OBJECT_SIM_OCEAN);
+  OceanBakeJob *oj = MEM_cnew<OceanBakeJob>("ocean bake job");
+  oj->owner = ob;
+  oj->ocean = ocean;
+  oj->och = och;
+  oj->omd = omd;
+
+  WM_jobs_customdata_set(wm_job, oj, oceanbake_free);
+  WM_jobs_timer(wm_job, 0.1, NC_OBJECT | ND_MODIFIER, NC_OBJECT | ND_MODIFIER);
+  WM_jobs_callbacks(wm_job, oceanbake_startjob, nullptr, nullptr, oceanbake_endjob);
+
+  WM_jobs_start(CTX_wm_manager(C), wm_job);
+
+  return OPERATOR_FINISHED;
+}
+
+static int ocean_bake_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return ocean_bake_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_ocean_bake(wmOperatorType *ot)
+{
+  ot->name = "Bake Ocean";
+  ot->description = "Bake an image sequence of ocean data";
+  ot->idname = "OBJECT_OT_ocean_bake";
+
+  ot->poll = ocean_bake_poll;
+  ot->invoke = ocean_bake_invoke;
+  ot->exec = ocean_bake_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+
+  RNA_def_boolean(ot->srna, "free", false, "Free", "Free the bake, rather than generating it");
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Laplacian-Deform Bind Operator
+ * \{ */
+
+static bool laplaciandeform_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_LaplacianDeformModifier, 0, false, false);
+}
+
+static int laplaciandeform_bind_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  LaplacianDeformModifierData *lmd = (LaplacianDeformModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_LaplacianDeform);
+
+  if (lmd == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (lmd->flag & MOD_LAPLACIANDEFORM_BIND) {
+    lmd->flag &= ~MOD_LAPLACIANDEFORM_BIND;
+  }
+  else {
+    lmd->flag |= MOD_LAPLACIANDEFORM_BIND;
+  }
+
+  LaplacianDeformModifierData *lmd_eval = (LaplacianDeformModifierData *)
+      BKE_modifier_get_evaluated(depsgraph, ob, &lmd->modifier);
+  lmd_eval->flag = lmd->flag;
+
+  /* Force modifier to run, it will call binding routine
+   * (this has to happen outside of depsgraph evaluation). */
+  object_force_modifier_bind_simple_options(depsgraph, ob, &lmd->modifier);
+
+  /* This is hard to know from the modifier itself whether the evaluation is
+   * happening for binding or not. So we copy all the required data here. */
+  lmd->verts_num = lmd_eval->verts_num;
+  if (lmd_eval->vertexco == nullptr) {
+    MEM_SAFE_FREE(lmd->vertexco);
+  }
+  else {
+    lmd->vertexco = static_cast<float *>(MEM_dupallocN(lmd_eval->vertexco));
+  }
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+  return OPERATOR_FINISHED;
+}
+
+static int laplaciandeform_bind_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return laplaciandeform_bind_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_laplaciandeform_bind(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Laplacian Deform Bind";
+  ot->description = "Bind mesh to system in laplacian deform modifier";
+  ot->idname = "OBJECT_OT_laplaciandeform_bind";
+
+  /* api callbacks */
+  ot->poll = laplaciandeform_poll;
+  ot->invoke = laplaciandeform_bind_invoke;
+  ot->exec = laplaciandeform_bind_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Surface Deform Bind Operator
+ * \{ */
+
+static bool surfacedeform_bind_poll(bContext *C)
+{
+  return edit_modifier_poll_generic(C, &RNA_SurfaceDeformModifier, 0, true, false);
+}
+
+static int surfacedeform_bind_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  SurfaceDeformModifierData *smd = (SurfaceDeformModifierData *)edit_modifier_property_get(
+      op, ob, eModifierType_SurfaceDeform);
+
+  if (smd == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  if (smd->flags & MOD_SDEF_BIND) {
+    smd->flags &= ~MOD_SDEF_BIND;
+  }
+  else if (smd->target) {
+    smd->flags |= MOD_SDEF_BIND;
+  }
+
+  SurfaceDeformModifierData *smd_eval = (SurfaceDeformModifierData *)BKE_modifier_get_evaluated(
+      depsgraph, ob, &smd->modifier);
+  smd_eval->flags = smd->flags;
+
+  /* Force modifier to run, it will call binding routine
+   * (this has to happen outside of depsgraph evaluation). */
+  object_force_modifier_bind_simple_options(depsgraph, ob, &smd->modifier);
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+  return OPERATOR_FINISHED;
+}
+
+static int surfacedeform_bind_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
+{
+  if (edit_modifier_invoke_properties(C, op)) {
+    return surfacedeform_bind_exec(C, op);
+  }
+  return OPERATOR_CANCELLED;
+}
+
+void OBJECT_OT_surfacedeform_bind(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Surface Deform Bind";
+  ot->description = "Bind mesh to target in surface deform modifier";
+  ot->idname = "OBJECT_OT_surfacedeform_bind";
+
+  /* api callbacks */
+  ot->poll = surfacedeform_bind_poll;
+  ot->invoke = surfacedeform_bind_invoke;
+  ot->exec = surfacedeform_bind_exec;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+  edit_modifier_properties(ot);
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Toggle Value or Attribute Operator
+ *
+ * \note This operator basically only exists to provide a better tooltip for the toggle button,
+ * since it is stored as an IDProperty. It also stops the button from being highlighted when
+ * "use_attribute" is on, which isn't expected.
+ * \{ */
+
+static int geometry_nodes_input_attribute_toggle_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = ED_object_active_context(C);
+
+  char modifier_name[MAX_NAME];
+  RNA_string_get(op->ptr, "modifier_name", modifier_name);
+  NodesModifierData *nmd = (NodesModifierData *)BKE_modifiers_findby_name(ob, modifier_name);
+  if (nmd == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  char prop_path[MAX_NAME];
+  RNA_string_get(op->ptr, "prop_path", prop_path);
+
+  PointerRNA mod_ptr;
+  RNA_pointer_create(&ob->id, &RNA_Modifier, nmd, &mod_ptr);
+
+  const int old_value = RNA_int_get(&mod_ptr, prop_path);
+  const int new_value = !old_value;
+  RNA_int_set(&mod_ptr, prop_path, new_value);
+
+  DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_geometry_nodes_input_attribute_toggle(wmOperatorType *ot)
+{
+  ot->name = "Input Attribute Toggle";
+  ot->description =
+      "Switch between an attribute and a single value to define the data for every element";
+  ot->idname = "OBJECT_OT_geometry_nodes_input_attribute_toggle";
+
+  ot->exec = geometry_nodes_input_attribute_toggle_exec;
+
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_INTERNAL;
+
+  RNA_def_string(ot->srna, "prop_path", nullptr, 0, "Prop Path", "");
+  RNA_def_string(ot->srna, "modifier_name", nullptr, MAX_NAME, "Modifier Name", "");
+}
+
+/** \} */
+
+/* ------------------------------------------------------------------- */
+/** \name Copy and Assign Geometry Node Group operator
+ * \{ */
+
+static int geometry_node_tree_copy_assign_exec(bContext *C, wmOperator *UNUSED(op))
+{
+  Main *bmain = CTX_data_main(C);
+  Object *ob = ED_object_active_context(C);
+
+  ModifierData *md = BKE_object_active_modifier(ob);
+  if (md->type != eModifierType_Nodes) {
+    return OPERATOR_CANCELLED;
+  }
+
+  NodesModifierData *nmd = (NodesModifierData *)md;
+  bNodeTree *tree = nmd->node_group;
+  if (tree == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  bNodeTree *new_tree = (bNodeTree *)BKE_id_copy_ex(
+      bmain, &tree->id, nullptr, LIB_ID_COPY_ACTIONS | LIB_ID_COPY_DEFAULT);
+
+  if (new_tree == nullptr) {
+    return OPERATOR_CANCELLED;
+  }
+
+  nmd->node_group = new_tree;
+  id_us_min(&tree->id);
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
+  return OPERATOR_FINISHED;
+}
+
+void OBJECT_OT_geometry_node_tree_copy_assign(wmOperatorType *ot)
+{
+  ot->name = "Copy Geometry Node Group";
+  ot->description = "Copy the active geometry node group and assign it to the active modifier";
+  ot->idname = "OBJECT_OT_geometry_node_tree_copy_assign";
+
+  ot->exec = geometry_node_tree_copy_assign_exec;
+
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+/** \} */