diff --git a/release/scripts/modules/rna_prop_ui.py b/release/scripts/modules/rna_prop_ui.py
index bafa2b28bbf..26a2f9ad89b 100644
--- a/release/scripts/modules/rna_prop_ui.py
+++ b/release/scripts/modules/rna_prop_ui.py
@@ -30,24 +30,6 @@ ARRAY_TYPES = (list, tuple, IDPropertyArray, Vector)
 MAX_DISPLAY_ROWS = 4
 
 
-def rna_idprop_ui_get(item, *, create=True):
-    try:
-        return item['_RNA_UI']
-    except:
-        if create:
-            item['_RNA_UI'] = {}
-            return item['_RNA_UI']
-        else:
-            return None
-
-
-def rna_idprop_ui_del(item):
-    try:
-        del item['_RNA_UI']
-    except KeyError:
-        pass
-
-
 def rna_idprop_quote_path(prop):
     return "[\"%s\"]" % bpy.utils.escape_identifier(prop)
 
@@ -59,32 +41,9 @@ def rna_idprop_ui_prop_update(item, prop):
         prop_rna.update()
 
 
-def rna_idprop_ui_prop_get(item, prop, *, create=True):
-
-    rna_ui = rna_idprop_ui_get(item, create=create)
-
-    if rna_ui is None:
-        return None
-
-    try:
-        return rna_ui[prop]
-    except:
-        rna_ui[prop] = {}
-        return rna_ui[prop]
-
-
-def rna_idprop_ui_prop_clear(item, prop, *, remove=True):
-    rna_ui = rna_idprop_ui_get(item, create=False)
-
-    if rna_ui is None:
-        return
-
-    try:
-        del rna_ui[prop]
-    except KeyError:
-        pass
-    if remove and len(item.keys()) == 1:
-        rna_idprop_ui_del(item)
+def rna_idprop_ui_prop_clear(item, prop):
+    ui_data = item.id_properties_ui(prop)
+    ui_data.clear()
 
 
 def rna_idprop_context_value(context, context_member, property_type):
@@ -106,8 +65,7 @@ def rna_idprop_context_value(context, context_member, property_type):
 
 def rna_idprop_has_properties(rna_item):
     keys = rna_item.keys()
-    nbr_props = len(keys)
-    return (nbr_props > 1) or (nbr_props and '_RNA_UI' not in keys)
+    return bool(keys)
 
 
 def rna_idprop_value_to_python(value):
@@ -126,31 +84,8 @@ def rna_idprop_value_item_type(value):
 
 
 def rna_idprop_ui_prop_default_set(item, prop, value):
-    defvalue = None
-    try:
-        prop_type, is_array = rna_idprop_value_item_type(item[prop])
-
-        if prop_type in {int, float, str}:
-            if is_array and isinstance(value, ARRAY_TYPES):
-                value = [prop_type(item) for item in value]
-                if any(value):
-                    defvalue = value
-            else:
-                defvalue = prop_type(value)
-    except KeyError:
-        pass
-    except ValueError:
-        pass
-
-    if defvalue:
-        rna_ui = rna_idprop_ui_prop_get(item, prop, create=True)
-        rna_ui["default"] = defvalue
-    else:
-        rna_ui = rna_idprop_ui_prop_get(item, prop)
-        if rna_ui:
-            rna_ui.pop("default", None)
-
-    return defvalue
+    ui_data = item.id_properties_ui(prop)
+    ui_data.update(default=value)
 
 
 def rna_idprop_ui_create(
@@ -163,7 +98,7 @@ def rna_idprop_ui_create(
 ):
     """Create and initialize a custom property with limits, defaults and other settings."""
 
-    proptype, is_array = rna_idprop_value_item_type(default)
+    proptype, _ = rna_idprop_value_item_type(default)
 
     # Sanitize limits
     if proptype is bool:
@@ -180,35 +115,22 @@ def rna_idprop_ui_create(
 
     rna_idprop_ui_prop_update(item, prop)
 
-    # Clear the UI settings
-    rna_ui_group = rna_idprop_ui_get(item, create=True)
-    rna_ui_group[prop] = {}
-    rna_ui = rna_ui_group[prop]
-
-    # Assign limits and default
-    if proptype in {int, float, bool}:
-        # The type must be exactly the same
-        rna_ui["min"] = proptype(min)
-        rna_ui["soft_min"] = proptype(soft_min)
-        rna_ui["max"] = proptype(max)
-        rna_ui["soft_max"] = proptype(soft_max)
-
-        if default and (not is_array or any(default)):
-            rna_ui["default"] = default
-
-        if is_array and subtype and subtype != 'NONE':
-            rna_ui["subtype"] = subtype
-
-    # Assign other settings
-    if description is not None:
-        rna_ui["description"] = description
+    # Update the UI settings.
+    ui_data = item.id_properties_ui(prop)
+    ui_data.update(
+        subtype=subtype,
+        min=min,
+        max=max,
+        soft_min=soft_min,
+        soft_max=soft_max,
+        description=description,
+        default=default,
+    )
 
     prop_path = rna_idprop_quote_path(prop)
 
     item.property_overridable_library_set(prop_path, overridable)
 
-    return rna_ui
-
 
 def draw(layout, context, context_member, property_type, *, use_edit=True):
 
@@ -254,10 +176,6 @@ def draw(layout, context, context_member, property_type, *, use_edit=True):
     flow = layout.grid_flow(row_major=False, columns=0, even_columns=True, even_rows=False, align=True)
 
     for key, val in items:
-
-        if key == '_RNA_UI':
-            continue
-
         is_rna = (key in rna_properties)
 
         # only show API defined for developers
diff --git a/release/scripts/startup/bl_operators/object.py b/release/scripts/startup/bl_operators/object.py
index d61bed71cab..df37db40102 100644
--- a/release/scripts/startup/bl_operators/object.py
+++ b/release/scripts/startup/bl_operators/object.py
@@ -970,7 +970,7 @@ class OBJECT_OT_assign_property_defaults(Operator):
     def assign_defaults(obj):
         from rna_prop_ui import rna_idprop_ui_prop_default_set
 
-        rna_properties = {'_RNA_UI'} | {prop.identifier for prop in obj.bl_rna.properties if prop.is_runtime}
+        rna_properties = {prop.identifier for prop in obj.bl_rna.properties if prop.is_runtime}
 
         for prop, value in obj.items():
             if prop not in rna_properties:
diff --git a/release/scripts/startup/bl_operators/wm.py b/release/scripts/startup/bl_operators/wm.py
index 6a3830ad1e4..989c067efec 100644
--- a/release/scripts/startup/bl_operators/wm.py
+++ b/release/scripts/startup/bl_operators/wm.py
@@ -1388,10 +1388,8 @@ class WM_OT_properties_edit(Operator):
 
     def execute(self, context):
         from rna_prop_ui import (
-            rna_idprop_ui_prop_get,
             rna_idprop_ui_prop_clear,
             rna_idprop_ui_prop_update,
-            rna_idprop_ui_prop_default_set,
             rna_idprop_value_item_type,
         )
 
@@ -1431,27 +1429,35 @@ class WM_OT_properties_edit(Operator):
         prop_type_new = type(prop_value)
         prop_type, is_array = rna_idprop_value_item_type(prop_value)
 
-        prop_ui = rna_idprop_ui_prop_get(item, prop)
+        ui_data = item.id_properties_ui(prop)
+        ui_data.update(subtype=self.subtype, description=self.description)
 
-        if prop_type in {float, int}:
-            prop_ui["min"] = prop_type(self.min)
-            prop_ui["max"] = prop_type(self.max)
-
-            if self.use_soft_limits:
-                prop_ui["soft_min"] = prop_type(self.soft_min)
-                prop_ui["soft_max"] = prop_type(self.soft_max)
-            else:
-                prop_ui["soft_min"] = prop_type(self.min)
-                prop_ui["soft_max"] = prop_type(self.max)
-
-        if prop_type == float and is_array and self.subtype != 'NONE':
-            prop_ui["subtype"] = self.subtype
-        else:
-            prop_ui.pop("subtype", None)
-
-        prop_ui["description"] = self.description
-
-        rna_idprop_ui_prop_default_set(item, prop, default_eval)
+        if prop_type == int:
+            if type(default_eval) == str:
+                self.report({'WARNING'}, "Could not evaluate number from default value")
+                default_eval = None
+            elif hasattr(default_eval, "__len__"):
+                default_eval = [int(round(value)) for value in default_eval]
+            ui_data.update(
+                min=int(round(self.min)),
+                max=int(round(self.max)),
+                soft_min=int(round(self.soft_min)),
+                soft_max=int(round(self.soft_max)),
+                default=default_eval,
+            )
+        elif prop_type == float:
+            if type(default_eval) == str:
+                self.report({'WARNING'}, "Could not evaluate number from default value")
+                default_eval = None
+            ui_data.update(
+                min=self.min,
+                max=self.max,
+                soft_min=self.soft_min,
+                soft_max=self.soft_max,
+                default=default_eval,
+            )
+        elif prop_type == str:
+            ui_data.update(default=self.default)
 
         # If we have changed the type of the property, update its potential anim curves!
         if prop_type_old != prop_type_new:
@@ -1492,7 +1498,6 @@ class WM_OT_properties_edit(Operator):
 
     def invoke(self, context, _event):
         from rna_prop_ui import (
-            rna_idprop_ui_prop_get,
             rna_idprop_value_to_python,
             rna_idprop_value_item_type
         )
@@ -1526,28 +1531,22 @@ class WM_OT_properties_edit(Operator):
             self.default = ""
 
         # setup defaults
-        prop_ui = rna_idprop_ui_prop_get(item, prop, create=False)
-        if prop_ui:
-            self.min = prop_ui.get("min", -1000000000)
-            self.max = prop_ui.get("max", 1000000000)
-            self.description = prop_ui.get("description", "")
-
-            defval = prop_ui.get("default", None)
-            if defval is not None:
-                self.default = str(rna_idprop_value_to_python(defval))
-
-            self.soft_min = prop_ui.get("soft_min", self.min)
-            self.soft_max = prop_ui.get("soft_max", self.max)
+        ui_data = item.id_properties_ui(prop)
+        rna_data = ui_data.as_dict()
+        self.subtype =  rna_data["subtype"]
+        if prop_type in {int, float}:
+            self.min = rna_data["min"]
+            self.max = rna_data["max"]
+            self.soft_min = rna_data["soft_min"]
+            self.soft_max = rna_data["soft_max"]
             self.use_soft_limits = (
                 self.min != self.soft_min or
                 self.max != self.soft_max
             )
+        if prop_type in {int, float, str}:
+            self.default = str(rna_data["default"])
 
-            subtype = prop_ui.get("subtype", None)
-        else:
-            subtype = None
-
-        self._init_subtype(prop_type, is_array, subtype)
+        self._init_subtype(prop_type, is_array, self.subtype)
 
         # store for comparison
         self._cmp_props = self._cmp_props_get()
@@ -1688,7 +1687,6 @@ class WM_OT_properties_remove(Operator):
 
     def execute(self, context):
         from rna_prop_ui import (
-            rna_idprop_ui_prop_clear,
             rna_idprop_ui_prop_update,
         )
         data_path = self.data_path
@@ -1701,7 +1699,6 @@ class WM_OT_properties_remove(Operator):
         prop = self.property
         rna_idprop_ui_prop_update(item, prop)
         del item[prop]
-        rna_idprop_ui_prop_clear(item, prop)
 
         return {'FINISHED'}
 
diff --git a/release/scripts/startup/keyingsets_builtins.py b/release/scripts/startup/keyingsets_builtins.py
index ceffeaaff6c..d9811b6c0ed 100644
--- a/release/scripts/startup/keyingsets_builtins.py
+++ b/release/scripts/startup/keyingsets_builtins.py
@@ -523,10 +523,6 @@ class WholeCharacterMixin:
 
         # go over all custom properties for bone
         for prop in bone.keys():
-            # ignore special "_RNA_UI" used for UI editing
-            if prop == "_RNA_UI":
-                continue
-
             # for now, just add all of 'em
             prop_rna = type(bone).bl_rna.properties.get(prop, None)
             if prop_rna is None:
diff --git a/source/blender/blenkernel/BKE_idprop.h b/source/blender/blenkernel/BKE_idprop.h
index a5cb6489194..c28ac63388b 100644
--- a/source/blender/blenkernel/BKE_idprop.h
+++ b/source/blender/blenkernel/BKE_idprop.h
@@ -32,6 +32,7 @@ struct BlendLibReader;
 struct BlendWriter;
 struct ID;
 struct IDProperty;
+struct IDPropertyUIData;
 
 typedef union IDPropertyTemplate {
   int i;
@@ -183,6 +184,10 @@ void IDP_Reset(struct IDProperty *prop, const struct IDProperty *reference);
 #  define IDP_Id(prop) ((ID *)(prop)->data.pointer)
 #endif
 
+int IDP_coerce_to_int_or_zero(const struct IDProperty *prop);
+float IDP_coerce_to_float_or_zero(const struct IDProperty *prop);
+double IDP_coerce_to_double_or_zero(const struct IDProperty *prop);
+
 /**
  * Call a callback for each idproperty in the hierarchy under given root one (included).
  *
@@ -209,6 +214,28 @@ void IDP_BlendReadData_impl(struct BlendDataReader *reader,
 void IDP_BlendReadLib(struct BlendLibReader *reader, struct IDProperty *prop);
 void IDP_BlendReadExpand(struct BlendExpander *expander, struct IDProperty *prop);
 
+typedef enum eIDPropertyUIDataType {
+  /** Other properties types that don't support RNA UI data. */
+  IDP_UI_DATA_TYPE_UNSUPPORTED = -1,
+  /** IDP_INT or IDP_ARRAY with subtype IDP_INT. */
+  IDP_UI_DATA_TYPE_INT = 0,
+  /** IDP_FLOAT and IDP_DOUBLE or IDP_ARRAY properties with a float or double subtypes. */
+  IDP_UI_DATA_TYPE_FLOAT = 1,
+  /** IDP_STRING properties. */
+  IDP_UI_DATA_TYPE_STRING = 2,
+  /** IDP_ID. */
+  IDP_UI_DATA_TYPE_ID = 3,
+} eIDPropertyUIDataType;
+
+bool IDP_ui_data_supported(const struct IDProperty *prop);
+eIDPropertyUIDataType IDP_ui_data_type(const struct IDProperty *prop);
+void IDP_ui_data_free(struct IDProperty *prop);
+void IDP_ui_data_free_unique_contents(struct IDPropertyUIData *ui_data,
+                                      eIDPropertyUIDataType type,
+                                      const struct IDPropertyUIData *other);
+struct IDPropertyUIData *IDP_ui_data_ensure(struct IDProperty *prop);
+struct IDPropertyUIData *IDP_ui_data_copy(const struct IDProperty *prop);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/blenkernel/intern/idprop.c b/source/blender/blenkernel/intern/idprop.c
index 7a88a00c44f..786df14756a 100644
--- a/source/blender/blenkernel/intern/idprop.c
+++ b/source/blender/blenkernel/intern/idprop.c
@@ -21,6 +21,7 @@
  * \ingroup bke
  */
 
+#include <limits.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -274,6 +275,43 @@ void IDP_FreeArray(IDProperty *prop)
   }
 }
 
+IDPropertyUIData *IDP_ui_data_copy(const IDProperty *prop)
+{
+  IDPropertyUIData *dst_ui_data = MEM_dupallocN(prop->ui_data);
+
+  /* Copy extra type specific data. */
+  switch (IDP_ui_data_type(prop)) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      const IDPropertyUIDataString *src = (const IDPropertyUIDataString *)prop->ui_data;
+      IDPropertyUIDataString *dst = (IDPropertyUIDataString *)dst_ui_data;
+      dst->default_value = MEM_dupallocN(src->default_value);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      const IDPropertyUIDataInt *src = (const IDPropertyUIDataInt *)prop->ui_data;
+      IDPropertyUIDataInt *dst = (IDPropertyUIDataInt *)dst_ui_data;
+      dst->default_array = MEM_dupallocN(src->default_array);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      const IDPropertyUIDataFloat *src = (const IDPropertyUIDataFloat *)prop->ui_data;
+      IDPropertyUIDataFloat *dst = (IDPropertyUIDataFloat *)dst_ui_data;
+      dst->default_array = MEM_dupallocN(src->default_array);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      break;
+    }
+  }
+
+  dst_ui_data->description = MEM_dupallocN(prop->ui_data->description);
+
+  return dst_ui_data;
+}
+
 static IDProperty *idp_generic_copy(const IDProperty *prop, const int UNUSED(flag))
 {
   IDProperty *newp = MEM_callocN(sizeof(IDProperty), __func__);
@@ -284,6 +322,10 @@ static IDProperty *idp_generic_copy(const IDProperty *prop, const int UNUSED(fla
   newp->data.val = prop->data.val;
   newp->data.val2 = prop->data.val2;
 
+  if (prop->ui_data != NULL) {
+    newp->ui_data = IDP_ui_data_copy(prop);
+  }
+
   return newp;
 }
 
@@ -679,6 +721,7 @@ bool IDP_InsertToGroup(IDProperty *group, IDProperty *previous, IDProperty *pnew
 void IDP_RemoveFromGroup(IDProperty *group, IDProperty *prop)
 {
   BLI_assert(group->type == IDP_GROUP);
+  BLI_assert(BLI_findindex(&group->data.group, prop) != -1);
 
   group->len--;
   BLI_remlink(&group->data.group, prop);
@@ -725,6 +768,60 @@ static void IDP_FreeGroup(IDProperty *prop, const bool do_id_user)
 /** \name Main Functions  (IDProperty Main API)
  * \{ */
 
+/**
+ * Return an int from an IDProperty with a compatible type. This should be avoided, but
+ * it's sometimes necessary, for example when legacy files have incorrect property types.
+ */
+int IDP_coerce_to_int_or_zero(const IDProperty *prop)
+{
+  switch (prop->type) {
+    case IDP_INT:
+      return IDP_Int(prop);
+    case IDP_DOUBLE:
+      return (int)IDP_Double(prop);
+    case IDP_FLOAT:
+      return (int)IDP_Float(prop);
+    default:
+      return 0;
+  }
+}
+
+/**
+ * Return a double from an IDProperty with a compatible type. This should be avoided, but
+ * it's sometimes necessary, for example when legacy files have incorrect property types.
+ */
+double IDP_coerce_to_double_or_zero(const IDProperty *prop)
+{
+  switch (prop->type) {
+    case IDP_DOUBLE:
+      return IDP_Double(prop);
+    case IDP_FLOAT:
+      return (double)IDP_Float(prop);
+    case IDP_INT:
+      return (double)IDP_Int(prop);
+    default:
+      return 0.0;
+  }
+}
+
+/**
+ * Return a float from an IDProperty with a compatible type. This should be avoided, but
+ * it's sometimes necessary, for example when legacy files have incorrect property types.
+ */
+float IDP_coerce_to_float_or_zero(const IDProperty *prop)
+{
+  switch (prop->type) {
+    case IDP_FLOAT:
+      return IDP_Float(prop);
+    case IDP_DOUBLE:
+      return (float)IDP_Double(prop);
+    case IDP_INT:
+      return (float)IDP_Int(prop);
+    default:
+      return 0.0f;
+  }
+}
+
 IDProperty *IDP_CopyProperty_ex(const IDProperty *prop, const int flag)
 {
   switch (prop->type) {
@@ -999,6 +1096,85 @@ IDProperty *IDP_New(const char type, const IDPropertyTemplate *val, const char *
   return prop;
 }
 
+/**
+ * Free allocated pointers in the UI data that isn't shared with the UI data in the #other
+ * argument. Useful for returning early on failure when updating UI data in place, or when
+ * replacing a subset of the UI data's allocated pointers.
+ */
+void IDP_ui_data_free_unique_contents(IDPropertyUIData *ui_data,
+                                      const eIDPropertyUIDataType type,
+                                      const IDPropertyUIData *other)
+{
+  if (ui_data->description != other->description) {
+    MEM_SAFE_FREE(ui_data->description);
+  }
+
+  switch (type) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      const IDPropertyUIDataString *other_string = (const IDPropertyUIDataString *)other;
+      IDPropertyUIDataString *ui_data_string = (IDPropertyUIDataString *)ui_data;
+      if (ui_data_string->default_value != other_string->default_value) {
+        MEM_SAFE_FREE(ui_data_string->default_value);
+      }
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      const IDPropertyUIDataInt *other_int = (const IDPropertyUIDataInt *)other;
+      IDPropertyUIDataInt *ui_data_int = (IDPropertyUIDataInt *)ui_data;
+      if (ui_data_int->default_array != other_int->default_array) {
+        MEM_SAFE_FREE(ui_data_int->default_array);
+      }
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      const IDPropertyUIDataFloat *other_float = (const IDPropertyUIDataFloat *)other;
+      IDPropertyUIDataFloat *ui_data_float = (IDPropertyUIDataFloat *)ui_data;
+      if (ui_data_float->default_array != other_float->default_array) {
+        MEM_SAFE_FREE(ui_data_float->default_array);
+      }
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      break;
+    }
+  }
+}
+
+void IDP_ui_data_free(IDProperty *prop)
+{
+  switch (IDP_ui_data_type(prop)) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      IDPropertyUIDataString *ui_data_string = (IDPropertyUIDataString *)prop->ui_data;
+      MEM_SAFE_FREE(ui_data_string->default_value);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      IDPropertyUIDataInt *ui_data_int = (IDPropertyUIDataInt *)prop->ui_data;
+      MEM_SAFE_FREE(ui_data_int->default_array);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      IDPropertyUIDataFloat *ui_data_float = (IDPropertyUIDataFloat *)prop->ui_data;
+      MEM_SAFE_FREE(ui_data_float->default_array);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      break;
+    }
+  }
+
+  MEM_SAFE_FREE(prop->ui_data->description);
+
+  MEM_freeN(prop->ui_data);
+  prop->ui_data = NULL;
+}
+
 /**
  * \note This will free allocated data, all child properties of arrays and groups, and unlink IDs!
  * But it does not free the actual IDProperty struct itself.
@@ -1024,6 +1200,10 @@ void IDP_FreePropertyContent_ex(IDProperty *prop, const bool do_id_user)
       }
       break;
   }
+
+  if (prop->ui_data != NULL) {
+    IDP_ui_data_free(prop);
+  }
 }
 
 void IDP_FreePropertyContent(IDProperty *prop)
@@ -1104,6 +1284,48 @@ void IDP_foreach_property(IDProperty *id_property_root,
 
 void IDP_WriteProperty_OnlyData(const IDProperty *prop, BlendWriter *writer);
 
+static void write_ui_data(const IDProperty *prop, BlendWriter *writer)
+{
+  IDPropertyUIData *ui_data = prop->ui_data;
+
+  BLO_write_string(writer, ui_data->description);
+
+  switch (IDP_ui_data_type(prop)) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      IDPropertyUIDataString *ui_data_string = (IDPropertyUIDataString *)ui_data;
+      BLO_write_string(writer, ui_data_string->default_value);
+      BLO_write_struct(writer, IDPropertyUIDataString, ui_data);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      BLO_write_struct(writer, IDPropertyUIDataID, ui_data);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      IDPropertyUIDataInt *ui_data_int = (IDPropertyUIDataInt *)ui_data;
+      if (prop->type == IDP_ARRAY) {
+        BLO_write_int32_array(
+            writer, (uint)ui_data_int->default_array_len, (int32_t *)ui_data_int->default_array);
+      }
+      BLO_write_struct(writer, IDPropertyUIDataInt, ui_data);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      IDPropertyUIDataFloat *ui_data_float = (IDPropertyUIDataFloat *)ui_data;
+      if (prop->type == IDP_ARRAY) {
+        BLO_write_double_array(
+            writer, (uint)ui_data_float->default_array_len, ui_data_float->default_array);
+      }
+      BLO_write_struct(writer, IDPropertyUIDataFloat, ui_data);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      BLI_assert_unreachable();
+      break;
+    }
+  }
+}
+
 static void IDP_WriteArray(const IDProperty *prop, BlendWriter *writer)
 {
   /* Remember to set #IDProperty.totallen to len in the linking code! */
@@ -1165,6 +1387,9 @@ void IDP_WriteProperty_OnlyData(const IDProperty *prop, BlendWriter *writer)
       IDP_WriteIDPArray(prop, writer);
       break;
   }
+  if (prop->ui_data != NULL) {
+    write_ui_data(prop, writer);
+  }
 }
 
 void IDP_BlendWrite(BlendWriter *writer, const IDProperty *prop)
@@ -1175,6 +1400,43 @@ void IDP_BlendWrite(BlendWriter *writer, const IDProperty *prop)
 
 static void IDP_DirectLinkProperty(IDProperty *prop, BlendDataReader *reader);
 
+static void read_ui_data(IDProperty *prop, BlendDataReader *reader)
+{
+  BLO_read_data_address(reader, &prop->ui_data);
+  BLO_read_data_address(reader, &prop->ui_data->description);
+
+  switch (IDP_ui_data_type(prop)) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      IDPropertyUIDataString *ui_data_string = (IDPropertyUIDataString *)prop->ui_data;
+      BLO_read_data_address(reader, &ui_data_string->default_value);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      IDPropertyUIDataInt *ui_data_int = (IDPropertyUIDataInt *)prop->ui_data;
+      if (prop->type == IDP_ARRAY) {
+        BLO_read_int32_array(
+            reader, ui_data_int->default_array_len, (int **)&ui_data_int->default_array);
+      }
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      IDPropertyUIDataFloat *ui_data_float = (IDPropertyUIDataFloat *)prop->ui_data;
+      if (prop->type == IDP_ARRAY) {
+        BLO_read_double_array(
+            reader, ui_data_float->default_array_len, (double **)&ui_data_float->default_array);
+      }
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      BLI_assert_unreachable();
+      break;
+    }
+  }
+}
+
 static void IDP_DirectLinkIDPArray(IDProperty *prop, BlendDataReader *reader)
 {
   /* since we didn't save the extra buffer, set totallen to len */
@@ -1279,6 +1541,10 @@ static void IDP_DirectLinkProperty(IDProperty *prop, BlendDataReader *reader)
       prop->subtype = 0;
       IDP_Int(prop) = 0;
   }
+
+  if (prop->ui_data != NULL) {
+    read_ui_data(prop, reader);
+  }
 }
 
 void IDP_BlendReadData_impl(BlendDataReader *reader, IDProperty **prop, const char *caller_func_id)
@@ -1358,4 +1624,74 @@ void IDP_BlendReadExpand(struct BlendExpander *expander, IDProperty *prop)
   }
 }
 
+eIDPropertyUIDataType IDP_ui_data_type(const IDProperty *prop)
+{
+  if (prop->type == IDP_STRING) {
+    return IDP_UI_DATA_TYPE_STRING;
+  }
+  if (prop->type == IDP_ID) {
+    return IDP_UI_DATA_TYPE_ID;
+  }
+  if (prop->type == IDP_INT || (prop->type == IDP_ARRAY && prop->subtype == IDP_INT)) {
+    return IDP_UI_DATA_TYPE_INT;
+  }
+  if (ELEM(prop->type, IDP_FLOAT, IDP_DOUBLE) ||
+      (prop->type == IDP_ARRAY && ELEM(prop->subtype, IDP_FLOAT, IDP_DOUBLE))) {
+    return IDP_UI_DATA_TYPE_FLOAT;
+  }
+  return IDP_UI_DATA_TYPE_UNSUPPORTED;
+}
+
+bool IDP_ui_data_supported(const IDProperty *prop)
+{
+  return IDP_ui_data_type(prop) != IDP_UI_DATA_TYPE_UNSUPPORTED;
+}
+
+IDPropertyUIData *IDP_ui_data_ensure(IDProperty *prop)
+{
+  if (prop->ui_data != NULL) {
+    return prop->ui_data;
+  }
+
+  switch (IDP_ui_data_type(prop)) {
+    case IDP_UI_DATA_TYPE_STRING: {
+      prop->ui_data = MEM_callocN(sizeof(IDPropertyUIDataString), __func__);
+      break;
+    }
+    case IDP_UI_DATA_TYPE_ID: {
+      IDPropertyUIDataID *ui_data = MEM_callocN(sizeof(IDPropertyUIDataID), __func__);
+      prop->ui_data = (IDPropertyUIData *)ui_data;
+      break;
+    }
+    case IDP_UI_DATA_TYPE_INT: {
+      IDPropertyUIDataInt *ui_data = MEM_callocN(sizeof(IDPropertyUIDataInt), __func__);
+      ui_data->min = -INT_MAX;
+      ui_data->max = INT_MAX;
+      ui_data->soft_min = -INT_MAX;
+      ui_data->soft_max = INT_MAX;
+      ui_data->step = 1;
+      prop->ui_data = (IDPropertyUIData *)ui_data;
+      break;
+    }
+    case IDP_UI_DATA_TYPE_FLOAT: {
+      IDPropertyUIDataFloat *ui_data = MEM_callocN(sizeof(IDPropertyUIDataFloat), __func__);
+      ui_data->min = -FLT_MAX;
+      ui_data->max = FLT_MAX;
+      ui_data->soft_min = -FLT_MAX;
+      ui_data->soft_max = FLT_MAX;
+      ui_data->step = 1.0f;
+      ui_data->precision = 3;
+      prop->ui_data = (IDPropertyUIData *)ui_data;
+      break;
+    }
+    case IDP_UI_DATA_TYPE_UNSUPPORTED: {
+      /* UI data not supported for remaining types, this shouldn't be called in those cases. */
+      BLI_assert_unreachable();
+      break;
+    }
+  }
+
+  return prop->ui_data;
+}
+
 /** \} */
diff --git a/source/blender/blenloader/intern/versioning_300.c b/source/blender/blenloader/intern/versioning_300.c
index aee6d798799..0253316dc3a 100644
--- a/source/blender/blenloader/intern/versioning_300.c
+++ b/source/blender/blenloader/intern/versioning_300.c
@@ -20,6 +20,10 @@
 /* allow readfile to use deprecated functionality */
 #define DNA_DEPRECATED_ALLOW
 
+#include <string.h>
+
+#include "MEM_guardedalloc.h"
+
 #include "BLI_listbase.h"
 #include "BLI_math_vector.h"
 #include "BLI_path_util.h"
@@ -46,10 +50,14 @@
 #include "BKE_deform.h"
 #include "BKE_fcurve.h"
 #include "BKE_fcurve_driver.h"
+#include "BKE_idprop.h"
 #include "BKE_lib_id.h"
 #include "BKE_main.h"
 #include "BKE_node.h"
 
+#include "RNA_access.h"
+#include "RNA_enum_types.h"
+
 #include "BLO_readfile.h"
 #include "MEM_guardedalloc.h"
 #include "readfile.h"
@@ -60,6 +68,238 @@
 
 #include "versioning_common.h"
 
+static IDProperty *idproperty_find_ui_container(IDProperty *idprop_group)
+{
+  LISTBASE_FOREACH (IDProperty *, prop, &idprop_group->data.group) {
+    if (prop->type == IDP_GROUP && STREQ(prop->name, "_RNA_UI")) {
+      return prop;
+    }
+  }
+  return NULL;
+}
+
+static void version_idproperty_move_data_int(IDPropertyUIDataInt *ui_data,
+                                             const IDProperty *prop_ui_data)
+{
+  IDProperty *min = IDP_GetPropertyFromGroup(prop_ui_data, "min");
+  if (min != NULL) {
+    ui_data->min = ui_data->soft_min = IDP_coerce_to_int_or_zero(min);
+  }
+  IDProperty *max = IDP_GetPropertyFromGroup(prop_ui_data, "max");
+  if (max != NULL) {
+    ui_data->max = ui_data->soft_max = IDP_coerce_to_int_or_zero(max);
+  }
+  IDProperty *soft_min = IDP_GetPropertyFromGroup(prop_ui_data, "soft_min");
+  if (soft_min != NULL) {
+    ui_data->soft_min = IDP_coerce_to_int_or_zero(soft_min);
+    ui_data->soft_min = MIN2(ui_data->soft_min, ui_data->min);
+  }
+  IDProperty *soft_max = IDP_GetPropertyFromGroup(prop_ui_data, "soft_max");
+  if (soft_max != NULL) {
+    ui_data->soft_max = IDP_coerce_to_int_or_zero(soft_max);
+    ui_data->soft_max = MAX2(ui_data->soft_max, ui_data->max);
+  }
+  IDProperty *step = IDP_GetPropertyFromGroup(prop_ui_data, "step");
+  if (step != NULL) {
+    ui_data->step = IDP_coerce_to_int_or_zero(soft_max);
+  }
+  IDProperty *default_value = IDP_GetPropertyFromGroup(prop_ui_data, "default");
+  if (default_value != NULL) {
+    if (default_value->type == IDP_ARRAY) {
+      if (default_value->subtype == IDP_INT) {
+        ui_data->default_array = MEM_dupallocN(IDP_Array(default_value));
+        ui_data->default_array_len = default_value->len;
+      }
+    }
+    else if (default_value->type == IDP_INT) {
+      ui_data->default_value = IDP_coerce_to_int_or_zero(default_value);
+    }
+  }
+}
+
+static void version_idproperty_move_data_float(IDPropertyUIDataFloat *ui_data,
+                                               const IDProperty *prop_ui_data)
+{
+  IDProperty *min = IDP_GetPropertyFromGroup(prop_ui_data, "min");
+  if (min != NULL) {
+    ui_data->min = ui_data->soft_min = IDP_coerce_to_double_or_zero(min);
+  }
+  IDProperty *max = IDP_GetPropertyFromGroup(prop_ui_data, "max");
+  if (max != NULL) {
+    ui_data->max = ui_data->soft_max = IDP_coerce_to_double_or_zero(min);
+  }
+  IDProperty *soft_min = IDP_GetPropertyFromGroup(prop_ui_data, "soft_min");
+  if (soft_min != NULL) {
+    ui_data->soft_min = IDP_coerce_to_double_or_zero(soft_min);
+    ui_data->soft_min = MAX2(ui_data->soft_min, ui_data->min);
+  }
+  IDProperty *soft_max = IDP_GetPropertyFromGroup(prop_ui_data, "soft_max");
+  if (soft_max != NULL) {
+    ui_data->soft_max = IDP_coerce_to_double_or_zero(soft_max);
+    ui_data->soft_max = MIN2(ui_data->soft_max, ui_data->max);
+  }
+  IDProperty *step = IDP_GetPropertyFromGroup(prop_ui_data, "step");
+  if (step != NULL) {
+    ui_data->step = IDP_coerce_to_float_or_zero(step);
+  }
+  IDProperty *precision = IDP_GetPropertyFromGroup(prop_ui_data, "precision");
+  if (precision != NULL) {
+    ui_data->precision = IDP_coerce_to_int_or_zero(precision);
+  }
+  IDProperty *default_value = IDP_GetPropertyFromGroup(prop_ui_data, "default");
+  if (default_value != NULL) {
+    if (default_value->type == IDP_ARRAY) {
+      if (ELEM(default_value->subtype, IDP_FLOAT, IDP_DOUBLE)) {
+        ui_data->default_array = MEM_dupallocN(IDP_Array(default_value));
+        ui_data->default_array_len = default_value->len;
+      }
+    }
+    else if (ELEM(default_value->type, IDP_DOUBLE, IDP_FLOAT)) {
+      ui_data->default_value = IDP_coerce_to_double_or_zero(default_value);
+    }
+  }
+}
+
+static void version_idproperty_move_data_string(IDPropertyUIDataString *ui_data,
+                                                const IDProperty *prop_ui_data)
+{
+  IDProperty *default_value = IDP_GetPropertyFromGroup(prop_ui_data, "default");
+  if (default_value != NULL && default_value->type == IDP_STRING) {
+    ui_data->default_value = BLI_strdup(IDP_String(default_value));
+  }
+}
+
+static void version_idproperty_ui_data(IDProperty *idprop_group)
+{
+  if (idprop_group == NULL) { /* NULL check here to reduce verbosity of calls to this function. */
+    return;
+  }
+
+  IDProperty *ui_container = idproperty_find_ui_container(idprop_group);
+  if (ui_container == NULL) {
+    return;
+  }
+
+  LISTBASE_FOREACH (IDProperty *, prop, &idprop_group->data.group) {
+    IDProperty *prop_ui_data = IDP_GetPropertyFromGroup(ui_container, prop->name);
+    if (prop_ui_data == NULL) {
+      continue;
+    }
+
+    if (!IDP_ui_data_supported(prop)) {
+      continue;
+    }
+
+    IDPropertyUIData *ui_data = IDP_ui_data_ensure(prop);
+
+    IDProperty *subtype = IDP_GetPropertyFromGroup(prop_ui_data, "subtype");
+    if (subtype != NULL && subtype->type == IDP_STRING) {
+      const char *subtype_string = IDP_String(subtype);
+      int result = PROP_NONE;
+      RNA_enum_value_from_id(rna_enum_property_subtype_items, subtype_string, &result);
+      ui_data->rna_subtype = result;
+    }
+
+    IDProperty *description = IDP_GetPropertyFromGroup(prop_ui_data, "description");
+    if (description != NULL && description->type == IDP_STRING) {
+      ui_data->description = BLI_strdup(IDP_String(description));
+    }
+
+    /* Type specific data. */
+    switch (IDP_ui_data_type(prop)) {
+      case IDP_UI_DATA_TYPE_STRING:
+        version_idproperty_move_data_string((IDPropertyUIDataString *)ui_data, prop_ui_data);
+        break;
+      case IDP_UI_DATA_TYPE_ID:
+        break;
+      case IDP_UI_DATA_TYPE_INT:
+        version_idproperty_move_data_int((IDPropertyUIDataInt *)ui_data, prop_ui_data);
+        break;
+      case IDP_UI_DATA_TYPE_FLOAT:
+        version_idproperty_move_data_float((IDPropertyUIDataFloat *)ui_data, prop_ui_data);
+        break;
+      case IDP_UI_DATA_TYPE_UNSUPPORTED:
+        BLI_assert_unreachable();
+        break;
+    }
+
+    IDP_FreeFromGroup(ui_container, prop_ui_data);
+  }
+
+  IDP_FreeFromGroup(idprop_group, ui_container);
+}
+
+static void do_versions_idproperty_bones_recursive(Bone *bone)
+{
+  version_idproperty_ui_data(bone->prop);
+  LISTBASE_FOREACH (Bone *, child_bone, &bone->childbase) {
+    do_versions_idproperty_bones_recursive(child_bone);
+  }
+}
+
+/**
+ * For every data block that supports them, initialize the new IDProperty UI data struct based on
+ * the old more complicated storage. Assumes only the top level of IDProperties below the parent
+ * group had UI data in a "_RNA_UI" group.
+ *
+ * \note The following IDProperty groups in DNA aren't exposed in the UI or are runtime-only, so
+ * they don't have UI data: wmOperator, bAddon, bUserMenuItem_Op, wmKeyMapItem, wmKeyConfigPref,
+ * uiList, FFMpegCodecData, View3DShading, bToolRef, TimeMarker, ViewLayer, bPoseChannel.
+ */
+static void do_versions_idproperty_ui_data(Main *bmain)
+{
+  /* ID data. */
+  ID *id;
+  FOREACH_MAIN_ID_BEGIN (bmain, id) {
+    IDProperty *idprop_group = IDP_GetProperties(id, false);
+    if (idprop_group == NULL) {
+      continue;
+    }
+    version_idproperty_ui_data(idprop_group);
+  }
+  FOREACH_MAIN_ID_END;
+
+  /* Bones. */
+  LISTBASE_FOREACH (bArmature *, armature, &bmain->armatures) {
+    LISTBASE_FOREACH (Bone *, bone, &armature->bonebase) {
+      do_versions_idproperty_bones_recursive(bone);
+    }
+  }
+
+  /* Nodes and node sockets. */
+  LISTBASE_FOREACH (bNodeTree *, ntree, &bmain->nodetrees) {
+    LISTBASE_FOREACH (bNode *, node, &ntree->nodes) {
+      version_idproperty_ui_data(node->prop);
+    }
+    LISTBASE_FOREACH (bNodeSocket *, socket, &ntree->inputs) {
+      version_idproperty_ui_data(socket->prop);
+    }
+    LISTBASE_FOREACH (bNodeSocket *, socket, &ntree->outputs) {
+      version_idproperty_ui_data(socket->prop);
+    }
+  }
+
+  /* The UI data from exposed node modifier properties is just copied from the corresponding node
+   * group, but the copying only runs when necessary, so we still need to version UI data here. */
+  LISTBASE_FOREACH (Object *, ob, &bmain->objects) {
+    LISTBASE_FOREACH (ModifierData *, md, &ob->modifiers) {
+      if (md->type == eModifierType_Nodes) {
+        NodesModifierData *nmd = (NodesModifierData *)md;
+        version_idproperty_ui_data(nmd->settings.properties);
+      }
+    }
+  }
+
+  /* Sequences. */
+  LISTBASE_FOREACH (Scene *, scene, &bmain->scenes) {
+    if (scene->ed != NULL) {
+      LISTBASE_FOREACH (Sequence *, seq, &scene->ed->seqbase) {
+        version_idproperty_ui_data(seq->prop);
+      }
+    }
+  }
+}
+
 static void sort_linked_ids(Main *bmain)
 {
   ListBase *lb;
@@ -252,6 +492,7 @@ void do_versions_after_linking_300(Main *bmain, ReportList *UNUSED(reports))
    */
   {
     /* Keep this block, even when empty. */
+    do_versions_idproperty_ui_data(bmain);
   }
 }
 
diff --git a/source/blender/io/alembic/exporter/abc_custom_props.cc b/source/blender/io/alembic/exporter/abc_custom_props.cc
index 4ea2fd03fff..e27a9012dab 100644
--- a/source/blender/io/alembic/exporter/abc_custom_props.cc
+++ b/source/blender/io/alembic/exporter/abc_custom_props.cc
@@ -60,9 +60,6 @@ void CustomPropertiesExporter::write_all(const IDProperty *group)
 
   /* Loop over the properties, just like IDP_foreach_property() does, but without the recursion. */
   LISTBASE_FOREACH (IDProperty *, id_property, &group->data.group) {
-    if (STREQ(id_property->name, "_RNA_UI")) {
-      continue;
-    }
     write(id_property);
   }
 }
diff --git a/source/blender/makesdna/DNA_ID.h b/source/blender/makesdna/DNA_ID.h
index 10a5a0f1c47..5b7c99f2545 100644
--- a/source/blender/makesdna/DNA_ID.h
+++ b/source/blender/makesdna/DNA_ID.h
@@ -59,6 +59,58 @@ typedef struct DrawDataList {
   struct DrawData *first, *last;
 } DrawDataList;
 
+typedef struct IDPropertyUIData {
+  /** Tooltip / property description pointer. Owned by the IDProperty. */
+  char *description;
+  /** RNA subtype, used for every type except string properties (PropertySubType). */
+  int rna_subtype;
+
+  char _pad[4];
+} IDPropertyUIData;
+
+/* IDP_UI_DATA_TYPE_INT */
+typedef struct IDPropertyUIDataInt {
+  IDPropertyUIData base;
+  int *default_array; /* Only for array properties. */
+  int default_array_len;
+  char _pad[4];
+
+  int min;
+  int max;
+  int soft_min;
+  int soft_max;
+  int step;
+  int default_value;
+} IDPropertyUIDataInt;
+
+/* IDP_UI_DATA_TYPE_FLOAT */
+typedef struct IDPropertyUIDataFloat {
+  IDPropertyUIData base;
+  double *default_array; /* Only for array properties. */
+  int default_array_len;
+  char _pad[4];
+
+  float step;
+  int precision;
+
+  double min;
+  double max;
+  double soft_min;
+  double soft_max;
+  double default_value;
+} IDPropertyUIDataFloat;
+
+/* IDP_UI_DATA_TYPE_STRING */
+typedef struct IDPropertyUIDataString {
+  IDPropertyUIData base;
+  char *default_value;
+} IDPropertyUIDataString;
+
+/* IDP_UI_DATA_TYPE_ID */
+typedef struct IDPropertyUIDataID {
+  IDPropertyUIData base;
+} IDPropertyUIDataID;
+
 typedef struct IDPropertyData {
   void *pointer;
   ListBase group;
@@ -87,6 +139,8 @@ typedef struct IDProperty {
   /* totallen is total length of allocated array/string, including a buffer.
    * Note that the buffering is mild; the code comes from python's list implementation. */
   int totallen;
+
+  IDPropertyUIData *ui_data;
 } IDProperty;
 
 #define MAX_IDPROP_NAME 64
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index b943a8fad5a..abbe609d0ef 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -1006,7 +1006,7 @@ int RNA_property_int_get_index(PointerRNA *ptr, PropertyRNA *prop, int index);
 void RNA_property_int_set_array(PointerRNA *ptr, PropertyRNA *prop, const int *values);
 void RNA_property_int_set_index(PointerRNA *ptr, PropertyRNA *prop, int index, int value);
 int RNA_property_int_get_default(PointerRNA *ptr, PropertyRNA *prop);
-bool RNA_property_int_set_default(PointerRNA *ptr, PropertyRNA *prop, int value);
+bool RNA_property_int_set_default(PropertyRNA *prop, int value);
 void RNA_property_int_get_default_array(PointerRNA *ptr, PropertyRNA *prop, int *values);
 int RNA_property_int_get_default_index(PointerRNA *ptr, PropertyRNA *prop, int index);
 
@@ -1018,7 +1018,7 @@ float RNA_property_float_get_index(PointerRNA *ptr, PropertyRNA *prop, int index
 void RNA_property_float_set_array(PointerRNA *ptr, PropertyRNA *prop, const float *values);
 void RNA_property_float_set_index(PointerRNA *ptr, PropertyRNA *prop, int index, float value);
 float RNA_property_float_get_default(PointerRNA *ptr, PropertyRNA *prop);
-bool RNA_property_float_set_default(PointerRNA *ptr, PropertyRNA *prop, float value);
+bool RNA_property_float_set_default(PropertyRNA *prop, float value);
 void RNA_property_float_get_default_array(PointerRNA *ptr, PropertyRNA *prop, float *values);
 float RNA_property_float_get_default_index(PointerRNA *ptr, PropertyRNA *prop, int index);
 
@@ -1028,7 +1028,7 @@ char *RNA_property_string_get_alloc(
 void RNA_property_string_set(PointerRNA *ptr, PropertyRNA *prop, const char *value);
 void RNA_property_string_set_bytes(PointerRNA *ptr, PropertyRNA *prop, const char *value, int len);
 int RNA_property_string_length(PointerRNA *ptr, PropertyRNA *prop);
-void RNA_property_string_get_default(PointerRNA *ptr, PropertyRNA *prop, char *value);
+void RNA_property_string_get_default(PropertyRNA *prop, char *value, int max_len);
 char *RNA_property_string_get_default_alloc(
     PointerRNA *ptr, PropertyRNA *prop, char *fixedbuf, int fixedlen, int *r_len);
 int RNA_property_string_default_length(PointerRNA *ptr, PropertyRNA *prop);
diff --git a/source/blender/makesrna/intern/rna_access.c b/source/blender/makesrna/intern/rna_access.c
index 8fa2d0ed849..2d6d5408aa0 100644
--- a/source/blender/makesrna/intern/rna_access.c
+++ b/source/blender/makesrna/intern/rna_access.c
@@ -246,130 +246,6 @@ void rna_idproperty_touch(IDProperty *idprop)
   idprop->flag &= ~IDP_FLAG_GHOST;
 }
 
-static IDProperty *rna_idproperty_ui_container(PropertyRNA *prop)
-{
-  IDProperty *idprop;
-
-  for (idprop = ((IDProperty *)prop)->prev; idprop; idprop = idprop->prev) {
-    if (STREQ(RNA_IDP_UI, idprop->name)) {
-      break;
-    }
-  }
-
-  if (idprop == NULL) {
-    for (idprop = ((IDProperty *)prop)->next; idprop; idprop = idprop->next) {
-      if (STREQ(RNA_IDP_UI, idprop->name)) {
-        break;
-      }
-    }
-  }
-
-  return idprop;
-}
-
-/* return a UI local ID prop definition for this prop */
-static const IDProperty *rna_idproperty_ui(const PropertyRNA *prop)
-{
-  IDProperty *idprop = rna_idproperty_ui_container((PropertyRNA *)prop);
-
-  if (idprop) {
-    return IDP_GetPropertyTypeFromGroup(idprop, ((IDProperty *)prop)->name, IDP_GROUP);
-  }
-
-  return NULL;
-}
-
-/* return or create a UI local ID prop definition for this prop */
-static IDProperty *rna_idproperty_ui_ensure(PointerRNA *ptr, PropertyRNA *prop, bool create)
-{
-  IDProperty *idprop = rna_idproperty_ui_container(prop);
-  IDPropertyTemplate dummy = {0};
-
-  if (idprop == NULL && create) {
-    IDProperty *props = RNA_struct_idprops(ptr, false);
-
-    /* Sanity check: props is the actual container of this property. */
-    if (props != NULL && BLI_findindex(&props->data.group, prop) >= 0) {
-      idprop = IDP_New(IDP_GROUP, &dummy, RNA_IDP_UI);
-
-      if (!IDP_AddToGroup(props, idprop)) {
-        IDP_FreePropertyContent(idprop);
-        return NULL;
-      }
-    }
-  }
-
-  if (idprop) {
-    const char *name = ((IDProperty *)prop)->name;
-    IDProperty *rv = IDP_GetPropertyTypeFromGroup(idprop, name, IDP_GROUP);
-
-    if (rv == NULL && create) {
-      rv = IDP_New(IDP_GROUP, &dummy, name);
-
-      if (!IDP_AddToGroup(idprop, rv)) {
-        IDP_FreePropertyContent(rv);
-        return NULL;
-      }
-    }
-
-    return rv;
-  }
-
-  return NULL;
-}
-
-static bool rna_idproperty_ui_set_default(PointerRNA *ptr,
-                                          PropertyRNA *prop,
-                                          const char type,
-                                          IDPropertyTemplate *value)
-{
-  BLI_assert(ELEM(type, IDP_INT, IDP_DOUBLE));
-
-  if (prop->magic == RNA_MAGIC) {
-    return false;
-  }
-
-  /* attempt to get the local ID values */
-  IDProperty *idp_ui = rna_idproperty_ui_ensure(ptr, prop, value != NULL);
-
-  if (idp_ui == NULL) {
-    return (value == NULL);
-  }
-
-  IDProperty *item = IDP_GetPropertyTypeFromGroup(idp_ui, "default", type);
-
-  if (value == NULL) {
-    if (item != NULL) {
-      IDP_RemoveFromGroup(idp_ui, item);
-    }
-  }
-  else {
-    if (item != NULL) {
-      switch (type) {
-        case IDP_INT:
-          IDP_Int(item) = value->i;
-          break;
-        case IDP_DOUBLE:
-          IDP_Double(item) = value->d;
-          break;
-        default:
-          BLI_assert(false);
-          return false;
-      }
-    }
-    else {
-      item = IDP_New(type, value, "default");
-
-      if (!IDP_AddToGroup(idp_ui, item)) {
-        IDP_FreePropertyContent(item);
-        return false;
-      }
-    }
-  }
-
-  return true;
-}
-
 IDProperty **RNA_struct_idprops_p(PointerRNA *ptr)
 {
   StructRNA *type = ptr->type;
@@ -693,28 +569,17 @@ static const char *rna_ensure_property_identifier(const PropertyRNA *prop)
 
 static const char *rna_ensure_property_description(const PropertyRNA *prop)
 {
-  const char *description = NULL;
-
   if (prop->magic == RNA_MAGIC) {
-    description = prop->description;
-  }
-  else {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item = IDP_GetPropertyTypeFromGroup(idp_ui, "description", IDP_STRING);
-      if (item) {
-        description = IDP_String(item);
-      }
-    }
-
-    if (description == NULL) {
-      description = ((IDProperty *)prop)->name; /* XXX: not correct. */
-    }
+    return prop->description;
   }
 
-  return description;
+  const IDProperty *idprop = (const IDProperty *)prop;
+  if (idprop->ui_data) {
+    const IDPropertyUIData *ui_data = idprop->ui_data;
+    return ui_data->description;
+  }
+
+  return "";
 }
 
 static const char *rna_ensure_property_name(const PropertyRNA *prop)
@@ -1196,19 +1061,9 @@ PropertySubType RNA_property_subtype(PropertyRNA *prop)
   if (prop->magic != RNA_MAGIC) {
     IDProperty *idprop = (IDProperty *)prop;
 
-    if (ELEM(idprop->type, IDP_INT, IDP_FLOAT, IDP_DOUBLE) ||
-        ((idprop->type == IDP_ARRAY) && ELEM(idprop->subtype, IDP_INT, IDP_FLOAT, IDP_DOUBLE))) {
-      const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-      if (idp_ui) {
-        IDProperty *item = IDP_GetPropertyTypeFromGroup(idp_ui, "subtype", IDP_STRING);
-
-        if (item) {
-          int result = PROP_NONE;
-          RNA_enum_value_from_id(rna_enum_property_subtype_items, IDP_String(item), &result);
-          return (PropertySubType)result;
-        }
-      }
+    if (idprop->ui_data) {
+      IDPropertyUIData *ui_data = idprop->ui_data;
+      return (PropertySubType)ui_data->rna_subtype;
     }
   }
 
@@ -1387,20 +1242,17 @@ void RNA_property_int_range(PointerRNA *ptr, PropertyRNA *prop, int *hardmin, in
   int softmin, softmax;
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "min", IDP_INT);
-      *hardmin = item ? IDP_Int(item) : INT_MIN;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "max", IDP_INT);
-      *hardmax = item ? IDP_Int(item) : INT_MAX;
-
-      return;
+    const IDProperty *idprop = (IDProperty *)prop;
+    if (idprop->ui_data) {
+      IDPropertyUIDataInt *ui_data = (IDPropertyUIDataInt *)idprop->ui_data;
+      *hardmin = ui_data->min;
+      *hardmax = ui_data->max;
     }
+    else {
+      *hardmin = INT_MIN;
+      *hardmax = INT_MAX;
+    }
+    return;
   }
 
   if (iprop->range) {
@@ -1428,23 +1280,19 @@ void RNA_property_int_ui_range(
   int hardmin, hardmax;
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "soft_min", IDP_INT);
-      *softmin = item ? IDP_Int(item) : INT_MIN;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "soft_max", IDP_INT);
-      *softmax = item ? IDP_Int(item) : INT_MAX;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "step", IDP_INT);
-      *step = item ? IDP_Int(item) : 1;
-
-      return;
+    const IDProperty *idprop = (IDProperty *)prop;
+    if (idprop->ui_data) {
+      IDPropertyUIDataInt *ui_data_int = (IDPropertyUIDataInt *)idprop->ui_data;
+      *softmin = ui_data_int->soft_min;
+      *softmax = ui_data_int->soft_max;
+      *step = ui_data_int->step;
     }
+    else {
+      *softmin = INT_MIN;
+      *softmax = INT_MAX;
+      *step = 1;
+    }
+    return;
   }
 
   *softmin = iprop->softmin;
@@ -1478,20 +1326,17 @@ void RNA_property_float_range(PointerRNA *ptr, PropertyRNA *prop, float *hardmin
   float softmin, softmax;
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "min", IDP_DOUBLE);
-      *hardmin = item ? (float)IDP_Double(item) : -FLT_MAX;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "max", IDP_DOUBLE);
-      *hardmax = item ? (float)IDP_Double(item) : FLT_MAX;
-
-      return;
+    const IDProperty *idprop = (IDProperty *)prop;
+    if (idprop->ui_data) {
+      IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)idprop->ui_data;
+      *hardmin = (float)ui_data->min;
+      *hardmax = (float)ui_data->max;
     }
+    else {
+      *hardmin = FLT_MIN;
+      *hardmax = FLT_MAX;
+    }
+    return;
   }
 
   if (fprop->range) {
@@ -1523,26 +1368,21 @@ void RNA_property_float_ui_range(PointerRNA *ptr,
   float hardmin, hardmax;
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "soft_min", IDP_DOUBLE);
-      *softmin = item ? (float)IDP_Double(item) : -FLT_MAX;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "soft_max", IDP_DOUBLE);
-      *softmax = item ? (float)IDP_Double(item) : FLT_MAX;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "step", IDP_DOUBLE);
-      *step = item ? (float)IDP_Double(item) : 1.0f;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "precision", IDP_DOUBLE);
-      *precision = item ? (float)IDP_Double(item) : 3.0f;
-
-      return;
+    const IDProperty *idprop = (IDProperty *)prop;
+    if (idprop->ui_data) {
+      IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)idprop->ui_data;
+      *softmin = (float)ui_data->soft_min;
+      *softmax = (float)ui_data->soft_max;
+      *step = ui_data->step;
+      *precision = (float)ui_data->precision;
     }
+    else {
+      *softmin = FLT_MIN;
+      *softmax = FLT_MAX;
+      *step = 1.0f;
+      *precision = 3.0f;
+    }
+    return;
   }
 
   *softmin = fprop->softmin;
@@ -2905,29 +2745,28 @@ int RNA_property_int_get_default(PointerRNA *UNUSED(ptr), PropertyRNA *prop)
   IntPropertyRNA *iprop = (IntPropertyRNA *)rna_ensure_property(prop);
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "default", IDP_INT);
-      return item ? IDP_Int(item) : iprop->defaultvalue;
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      const IDPropertyUIDataInt *ui_data = (const IDPropertyUIDataInt *)idprop->ui_data;
+      return ui_data->default_value;
     }
   }
 
   return iprop->defaultvalue;
 }
 
-bool RNA_property_int_set_default(PointerRNA *ptr, PropertyRNA *prop, int value)
+bool RNA_property_int_set_default(PropertyRNA *prop, int value)
 {
-  if (value != 0) {
-    IDPropertyTemplate val = {
-        .i = value,
-    };
-    return rna_idproperty_ui_set_default(ptr, prop, IDP_INT, &val);
+  if (prop->magic == RNA_MAGIC) {
+    return false;
   }
-  return rna_idproperty_ui_set_default(ptr, prop, IDP_INT, NULL);
+
+  IDProperty *idprop = (IDProperty *)prop;
+  BLI_assert(idprop->type == IDP_INT);
+
+  IDPropertyUIDataInt *ui_data = (IDPropertyUIDataInt *)IDP_ui_data_ensure(idprop);
+  ui_data->default_value = value;
+  return true;
 }
 
 void RNA_property_int_get_default_array(PointerRNA *ptr, PropertyRNA *prop, int *values)
@@ -2940,17 +2779,22 @@ void RNA_property_int_get_default_array(PointerRNA *ptr, PropertyRNA *prop, int
   if (prop->magic != RNA_MAGIC) {
     int length = rna_ensure_property_array_length(ptr, prop);
 
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-    IDProperty *item = idp_ui ? IDP_GetPropertyFromGroup(idp_ui, "default") : NULL;
-
-    int defval = (item && item->type == IDP_INT) ? IDP_Int(item) : iprop->defaultvalue;
-
-    if (item && item->type == IDP_ARRAY && item->subtype == IDP_INT) {
-      rna_property_int_fill_default_array_values(
-          IDP_Array(item), item->len, defval, length, values);
-    }
-    else {
-      rna_property_int_fill_default_array_values(NULL, 0, defval, length, values);
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      BLI_assert(idprop->type == IDP_ARRAY);
+      BLI_assert(idprop->subtype == IDP_INT);
+      const IDPropertyUIDataInt *ui_data = (const IDPropertyUIDataInt *)idprop->ui_data;
+      if (ui_data->default_array) {
+        rna_property_int_fill_default_array_values(ui_data->default_array,
+                                                   ui_data->default_array_len,
+                                                   ui_data->default_value,
+                                                   length,
+                                                   values);
+      }
+      else {
+        rna_property_int_fill_default_array_values(
+            NULL, 0, ui_data->default_value, length, values);
+      }
     }
   }
   else if (prop->arraydimension == 0) {
@@ -3066,6 +2910,26 @@ static void rna_property_float_fill_default_array_values(
   }
 }
 
+/**
+ * The same logic as #rna_property_float_fill_default_array_values for a double array.
+ */
+static void rna_property_float_fill_default_array_values_double(const double *default_array,
+                                                                const int default_array_len,
+                                                                const double default_value,
+                                                                const int out_length,
+                                                                float *r_values)
+{
+  const int array_copy_len = MIN2(out_length, default_array_len);
+
+  for (int i = 0; i < array_copy_len; i++) {
+    r_values[i] = (float)default_array[i];
+  }
+
+  for (int i = array_copy_len; i < out_length; i++) {
+    r_values[i] = (float)default_value;
+  }
+}
+
 static void rna_property_float_get_default_array_values(PointerRNA *ptr,
                                                         FloatPropertyRNA *fprop,
                                                         float *r_values)
@@ -3268,29 +3132,29 @@ float RNA_property_float_get_default(PointerRNA *UNUSED(ptr), PropertyRNA *prop)
   BLI_assert(RNA_property_array_check(prop) == false);
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "default", IDP_DOUBLE);
-      return item ? IDP_Double(item) : fprop->defaultvalue;
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      BLI_assert(ELEM(idprop->type, IDP_FLOAT, IDP_DOUBLE));
+      const IDPropertyUIDataFloat *ui_data = (const IDPropertyUIDataFloat *)idprop->ui_data;
+      return (float)ui_data->default_value;
     }
   }
 
   return fprop->defaultvalue;
 }
 
-bool RNA_property_float_set_default(PointerRNA *ptr, PropertyRNA *prop, float value)
+bool RNA_property_float_set_default(PropertyRNA *prop, float value)
 {
-  if (value != 0) {
-    IDPropertyTemplate val = {
-        .d = value,
-    };
-    return rna_idproperty_ui_set_default(ptr, prop, IDP_DOUBLE, &val);
+  if (prop->magic == RNA_MAGIC) {
+    return false;
   }
-  return rna_idproperty_ui_set_default(ptr, prop, IDP_DOUBLE, NULL);
+
+  IDProperty *idprop = (IDProperty *)prop;
+  BLI_assert(idprop->type == IDP_FLOAT);
+
+  IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)IDP_ui_data_ensure(idprop);
+  ui_data->default_value = (double)value;
+  return true;
 }
 
 void RNA_property_float_get_default_array(PointerRNA *ptr, PropertyRNA *prop, float *values)
@@ -3303,23 +3167,16 @@ void RNA_property_float_get_default_array(PointerRNA *ptr, PropertyRNA *prop, fl
   if (prop->magic != RNA_MAGIC) {
     int length = rna_ensure_property_array_length(ptr, prop);
 
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-    IDProperty *item = idp_ui ? IDP_GetPropertyFromGroup(idp_ui, "default") : NULL;
-
-    float defval = (item && item->type == IDP_DOUBLE) ? IDP_Double(item) : fprop->defaultvalue;
-
-    if (item && item->type == IDP_ARRAY && item->subtype == IDP_DOUBLE) {
-      double *defarr = IDP_Array(item);
-      for (int i = 0; i < length; i++) {
-        values[i] = (i < item->len) ? (float)defarr[i] : defval;
-      }
-    }
-    else if (item && item->type == IDP_ARRAY && item->subtype == IDP_FLOAT) {
-      rna_property_float_fill_default_array_values(
-          IDP_Array(item), item->len, defval, length, values);
-    }
-    else {
-      rna_property_float_fill_default_array_values(NULL, 0, defval, length, values);
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      BLI_assert(idprop->type == IDP_ARRAY);
+      BLI_assert(ELEM(idprop->subtype, IDP_FLOAT, IDP_DOUBLE));
+      const IDPropertyUIDataFloat *ui_data = (const IDPropertyUIDataFloat *)idprop->ui_data;
+      rna_property_float_fill_default_array_values_double(ui_data->default_array,
+                                                          ui_data->default_array_len,
+                                                          ui_data->default_value,
+                                                          length,
+                                                          values);
     }
   }
   else if (prop->arraydimension == 0) {
@@ -3510,22 +3367,17 @@ void RNA_property_string_set_bytes(PointerRNA *ptr, PropertyRNA *prop, const cha
   }
 }
 
-void RNA_property_string_get_default(PointerRNA *UNUSED(ptr), PropertyRNA *prop, char *value)
+void RNA_property_string_get_default(PropertyRNA *prop, char *value, const int max_len)
 {
   StringPropertyRNA *sprop = (StringPropertyRNA *)rna_ensure_property(prop);
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "default", IDP_STRING);
-      if (item) {
-        strcpy(value, IDP_String(item));
-        return;
-      }
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      BLI_assert(idprop->type == IDP_STRING);
+      const IDPropertyUIDataString *ui_data = (const IDPropertyUIDataString *)idprop->ui_data;
+      BLI_strncpy(value, ui_data->default_value, max_len);
+      return;
     }
 
     strcpy(value, "");
@@ -3554,7 +3406,7 @@ char *RNA_property_string_get_default_alloc(
     buf = MEM_callocN(sizeof(char) * (length + 1), __func__);
   }
 
-  RNA_property_string_get_default(ptr, prop, buf);
+  RNA_property_string_get_default(prop, buf, length + 1);
 
   if (r_len) {
     *r_len = length;
@@ -3569,15 +3421,12 @@ int RNA_property_string_default_length(PointerRNA *UNUSED(ptr), PropertyRNA *pro
   StringPropertyRNA *sprop = (StringPropertyRNA *)rna_ensure_property(prop);
 
   if (prop->magic != RNA_MAGIC) {
-    /* attempt to get the local ID values */
-    const IDProperty *idp_ui = rna_idproperty_ui(prop);
-
-    if (idp_ui) {
-      IDProperty *item;
-
-      item = IDP_GetPropertyTypeFromGroup(idp_ui, "default", IDP_STRING);
-      if (item) {
-        return strlen(IDP_String(item));
+    const IDProperty *idprop = (const IDProperty *)prop;
+    if (idprop->ui_data) {
+      BLI_assert(idprop->type == IDP_STRING);
+      const IDPropertyUIDataString *ui_data = (const IDPropertyUIDataString *)idprop->ui_data;
+      if (ui_data->default_value != NULL) {
+        return strlen(ui_data->default_value);
       }
     }
 
@@ -8200,12 +8049,12 @@ bool RNA_property_assign_default(PointerRNA *ptr, PropertyRNA *prop)
   switch (RNA_property_type(prop)) {
     case PROP_INT: {
       int value = RNA_property_int_get(ptr, prop);
-      return RNA_property_int_set_default(ptr, prop, value);
+      return RNA_property_int_set_default(prop, value);
     }
 
     case PROP_FLOAT: {
       float value = RNA_property_float_get(ptr, prop);
-      return RNA_property_float_set_default(ptr, prop, value);
+      return RNA_property_float_set_default(prop, value);
     }
 
     default:
diff --git a/source/blender/makesrna/intern/rna_internal_types.h b/source/blender/makesrna/intern/rna_internal_types.h
index 479306e8c06..22a9b9d930a 100644
--- a/source/blender/makesrna/intern/rna_internal_types.h
+++ b/source/blender/makesrna/intern/rna_internal_types.h
@@ -42,9 +42,6 @@ struct bContext;
 
 typedef struct IDProperty IDProperty;
 
-/* store local properties here */
-#define RNA_IDP_UI "_RNA_UI"
-
 /* Function Callbacks */
 
 typedef void (*UpdateFunc)(struct Main *main, struct Scene *scene, struct PointerRNA *ptr);
diff --git a/source/blender/modifiers/intern/MOD_nodes.cc b/source/blender/modifiers/intern/MOD_nodes.cc
index 620c7ef438a..9d8630b21e7 100644
--- a/source/blender/modifiers/intern/MOD_nodes.cc
+++ b/source/blender/modifiers/intern/MOD_nodes.cc
@@ -289,348 +289,178 @@ static bool logging_enabled(const ModifierEvalContext *ctx)
   return true;
 }
 
-/**
- * This code is responsible for creating the new property and also creating the group of
- * properties in the prop_ui_container group for the UI info, the mapping for which is
- * scattered about in RNA_access.c.
- *
- * TODO(Hans): Codify this with some sort of table or refactor IDProperty use in RNA_access.c.
- */
-struct SocketPropertyType {
-  /* Create the actual property used to store the data for the modifier. */
-  IDProperty *(*create_prop)(const bNodeSocket &socket, const char *name);
-  /* Reused to build the "soft_min" property too. */
-  IDProperty *(*create_min_ui_prop)(const bNodeSocket &socket, const char *name);
-  /* Reused to build the "soft_max" property too. */
-  IDProperty *(*create_max_ui_prop)(const bNodeSocket &socket, const char *name);
-  /* This uses the same values as #create_prop, but sometimes the type is different, so it can't
-   * be the same function. */
-  IDProperty *(*create_default_ui_prop)(const bNodeSocket &socket, const char *name);
-  PropertyType (*rna_subtype_get)(const bNodeSocket &socket);
-  bool (*is_correct_type)(const IDProperty &property);
-  void (*init_cpp_value)(const IDProperty &property, void *r_value);
-};
-
-static IDProperty *socket_add_property(IDProperty *settings_prop_group,
-                                       IDProperty *ui_container,
-                                       const SocketPropertyType &property_type,
-                                       const bNodeSocket &socket)
+static IDProperty *id_property_create_from_socket(const bNodeSocket &socket)
 {
-  const char *new_prop_name = socket.identifier;
-  /* Add the property actually storing the data to the modifier's group. */
-  IDProperty *prop = property_type.create_prop(socket, new_prop_name);
-  IDP_AddToGroup(settings_prop_group, prop);
-
-  prop->flag |= IDP_FLAG_OVERRIDABLE_LIBRARY;
-
-  /* Make the group in the UI container group to hold the property's UI settings. */
-  IDProperty *prop_ui_group;
-  {
-    IDPropertyTemplate idprop = {0};
-    prop_ui_group = IDP_New(IDP_GROUP, &idprop, new_prop_name);
-    IDP_AddToGroup(ui_container, prop_ui_group);
-  }
-
-  /* Set property description (tooltip). */
-  IDPropertyTemplate property_description_template;
-  property_description_template.string.str = socket.description;
-  property_description_template.string.len = BLI_strnlen(socket.description, MAX_NAME) + 1;
-  property_description_template.string.subtype = IDP_STRING_SUB_UTF8;
-  IDProperty *description = IDP_New(IDP_STRING, &property_description_template, "description");
-  IDP_AddToGroup(prop_ui_group, description);
-
-  /* Create the properties for the socket's UI settings. */
-  if (property_type.create_min_ui_prop != nullptr) {
-    IDP_AddToGroup(prop_ui_group, property_type.create_min_ui_prop(socket, "min"));
-    IDP_AddToGroup(prop_ui_group, property_type.create_min_ui_prop(socket, "soft_min"));
-  }
-  if (property_type.create_max_ui_prop != nullptr) {
-    IDP_AddToGroup(prop_ui_group, property_type.create_max_ui_prop(socket, "max"));
-    IDP_AddToGroup(prop_ui_group, property_type.create_max_ui_prop(socket, "soft_max"));
-  }
-  if (property_type.create_default_ui_prop != nullptr) {
-    IDP_AddToGroup(prop_ui_group, property_type.create_default_ui_prop(socket, "default"));
-  }
-  if (property_type.rna_subtype_get != nullptr) {
-    const char *subtype_identifier = nullptr;
-    RNA_enum_identifier(rna_enum_property_subtype_items,
-                        property_type.rna_subtype_get(socket),
-                        &subtype_identifier);
-
-    if (subtype_identifier != nullptr) {
-      IDPropertyTemplate idprop = {0};
-      idprop.string.str = subtype_identifier;
-      idprop.string.len = BLI_strnlen(subtype_identifier, MAX_NAME) + 1;
-      IDP_AddToGroup(prop_ui_group, IDP_New(IDP_STRING, &idprop, "subtype"));
-    }
-  }
-
-  return prop;
-}
-
-static const SocketPropertyType *get_socket_property_type(const bNodeSocket &bsocket)
-{
-  switch (bsocket.type) {
+  switch (socket.type) {
     case SOCK_FLOAT: {
-      static const SocketPropertyType float_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueFloat *value = (bNodeSocketValueFloat *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.f = value->value;
-            return IDP_New(IDP_FLOAT, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueFloat *value = (bNodeSocketValueFloat *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.d = value->min;
-            return IDP_New(IDP_DOUBLE, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueFloat *value = (bNodeSocketValueFloat *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.d = value->max;
-            return IDP_New(IDP_DOUBLE, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueFloat *value = (bNodeSocketValueFloat *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.d = value->value;
-            return IDP_New(IDP_DOUBLE, &idprop, name);
-          },
-          [](const bNodeSocket &socket) {
-            return (PropertyType)((bNodeSocketValueFloat *)socket.default_value)->subtype;
-          },
-          [](const IDProperty &property) { return ELEM(property.type, IDP_FLOAT, IDP_DOUBLE); },
-          [](const IDProperty &property, void *r_value) {
-            if (property.type == IDP_FLOAT) {
-              *(float *)r_value = IDP_Float(&property);
-            }
-            else if (property.type == IDP_DOUBLE) {
-              *(float *)r_value = (float)IDP_Double(&property);
-            }
-          },
-      };
-      return &float_type;
+      bNodeSocketValueFloat *value = (bNodeSocketValueFloat *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.f = value->value;
+      IDProperty *property = IDP_New(IDP_FLOAT, &idprop, socket.identifier);
+      IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)IDP_ui_data_ensure(property);
+      ui_data->base.rna_subtype = value->subtype;
+      ui_data->min = ui_data->soft_min = (double)value->min;
+      ui_data->max = ui_data->soft_max = (double)value->max;
+      ui_data->default_value = value->value;
+      return property;
     }
     case SOCK_INT: {
-      static const SocketPropertyType int_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueInt *value = (bNodeSocketValueInt *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->value;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueInt *value = (bNodeSocketValueInt *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->min;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueInt *value = (bNodeSocketValueInt *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->max;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueInt *value = (bNodeSocketValueInt *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->value;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &socket) {
-            return (PropertyType)((bNodeSocketValueInt *)socket.default_value)->subtype;
-          },
-          [](const IDProperty &property) { return property.type == IDP_INT; },
-          [](const IDProperty &property, void *r_value) { *(int *)r_value = IDP_Int(&property); },
-      };
-      return &int_type;
+      bNodeSocketValueInt *value = (bNodeSocketValueInt *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.i = value->value;
+      IDProperty *property = IDP_New(IDP_INT, &idprop, socket.identifier);
+      IDPropertyUIDataInt *ui_data = (IDPropertyUIDataInt *)IDP_ui_data_ensure(property);
+      ui_data->base.rna_subtype = value->subtype;
+      ui_data->min = ui_data->soft_min = value->min;
+      ui_data->max = ui_data->soft_max = value->max;
+      ui_data->default_value = value->value;
+      return property;
     }
     case SOCK_VECTOR: {
-      static const SocketPropertyType vector_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueVector *value = (bNodeSocketValueVector *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.array.len = 3;
-            idprop.array.type = IDP_FLOAT;
-            IDProperty *property = IDP_New(IDP_ARRAY, &idprop, name);
-            copy_v3_v3((float *)IDP_Array(property), value->value);
-            return property;
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueVector *value = (bNodeSocketValueVector *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.d = value->min;
-            return IDP_New(IDP_DOUBLE, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueVector *value = (bNodeSocketValueVector *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.d = value->max;
-            return IDP_New(IDP_DOUBLE, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueVector *value = (bNodeSocketValueVector *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.array.len = 3;
-            idprop.array.type = IDP_FLOAT;
-            IDProperty *property = IDP_New(IDP_ARRAY, &idprop, name);
-            copy_v3_v3((float *)IDP_Array(property), value->value);
-            return property;
-          },
-          [](const bNodeSocket &socket) {
-            return (PropertyType)((bNodeSocketValueVector *)socket.default_value)->subtype;
-          },
-          [](const IDProperty &property) {
-            return property.type == IDP_ARRAY && property.subtype == IDP_FLOAT &&
-                   property.len == 3;
-          },
-          [](const IDProperty &property, void *r_value) {
-            copy_v3_v3((float *)r_value, (const float *)IDP_Array(&property));
-          },
-      };
-      return &vector_type;
+      bNodeSocketValueVector *value = (bNodeSocketValueVector *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.array.len = 3;
+      idprop.array.type = IDP_FLOAT;
+      IDProperty *property = IDP_New(IDP_ARRAY, &idprop, socket.identifier);
+      copy_v3_v3((float *)IDP_Array(property), value->value);
+      IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)IDP_ui_data_ensure(property);
+      ui_data->base.rna_subtype = value->subtype;
+      ui_data->min = ui_data->soft_min = (double)value->min;
+      ui_data->max = ui_data->soft_max = (double)value->max;
+      ui_data->default_array = (double *)MEM_mallocN(sizeof(double[3]), "mod_prop_default");
+      ui_data->default_array_len = 3;
+      for (int i = 3; i < 3; i++) {
+        ui_data->default_array[i] = (double)value->value[i];
+      }
+      return property;
     }
     case SOCK_BOOLEAN: {
-      static const SocketPropertyType boolean_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueBoolean *value = (bNodeSocketValueBoolean *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->value != 0;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &UNUSED(socket), const char *name) {
-            IDPropertyTemplate idprop = {0};
-            idprop.i = 0;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &UNUSED(socket), const char *name) {
-            IDPropertyTemplate idprop = {0};
-            idprop.i = 1;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueBoolean *value = (bNodeSocketValueBoolean *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.i = value->value != 0;
-            return IDP_New(IDP_INT, &idprop, name);
-          },
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_INT; },
-          [](const IDProperty &property, void *r_value) {
-            *(bool *)r_value = IDP_Int(&property) != 0;
-          },
-      };
-      return &boolean_type;
+      bNodeSocketValueBoolean *value = (bNodeSocketValueBoolean *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.i = value->value != 0;
+      IDProperty *property = IDP_New(IDP_INT, &idprop, socket.identifier);
+      IDPropertyUIDataInt *ui_data = (IDPropertyUIDataInt *)IDP_ui_data_ensure(property);
+      ui_data->min = ui_data->soft_min = 0;
+      ui_data->max = ui_data->soft_max = 1;
+      ui_data->default_value = value->value != 0;
+      return property;
     }
     case SOCK_STRING: {
-      static const SocketPropertyType string_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueString *value = (bNodeSocketValueString *)socket.default_value;
-            return IDP_NewString(
-                value->value, name, BLI_strnlen(value->value, sizeof(value->value)) + 1);
-          },
-          nullptr,
-          nullptr,
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueString *value = (bNodeSocketValueString *)socket.default_value;
-            return IDP_NewString(
-                value->value, name, BLI_strnlen(value->value, sizeof(value->value)) + 1);
-          },
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_STRING; },
-          [](const IDProperty &property, void *r_value) {
-            new (r_value) std::string(IDP_String(&property));
-          },
-      };
-      return &string_type;
+      bNodeSocketValueString *value = (bNodeSocketValueString *)socket.default_value;
+      IDProperty *property = IDP_NewString(
+          value->value, socket.identifier, BLI_strnlen(value->value, sizeof(value->value)) + 1);
+      IDPropertyUIDataString *ui_data = (IDPropertyUIDataString *)IDP_ui_data_ensure(property);
+      ui_data->default_value = BLI_strdup(value->value);
+      return property;
     }
     case SOCK_OBJECT: {
-      static const SocketPropertyType object_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueObject *value = (bNodeSocketValueObject *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.id = (ID *)value->value;
-            return IDP_New(IDP_ID, &idprop, name);
-          },
-          nullptr,
-          nullptr,
-          nullptr,
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_ID; },
-          [](const IDProperty &property, void *r_value) {
-            ID *id = IDP_Id(&property);
-            Object *object = (id && GS(id->name) == ID_OB) ? (Object *)id : nullptr;
-            *(Object **)r_value = object;
-          },
-      };
-      return &object_type;
+      bNodeSocketValueObject *value = (bNodeSocketValueObject *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.id = (ID *)value->value;
+      return IDP_New(IDP_ID, &idprop, socket.identifier);
     }
     case SOCK_COLLECTION: {
-      static const SocketPropertyType collection_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueCollection *value = (bNodeSocketValueCollection *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.id = (ID *)value->value;
-            return IDP_New(IDP_ID, &idprop, name);
-          },
-          nullptr,
-          nullptr,
-          nullptr,
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_ID; },
-          [](const IDProperty &property, void *r_value) {
-            ID *id = IDP_Id(&property);
-            Collection *collection = (id && GS(id->name) == ID_GR) ? (Collection *)id : nullptr;
-            *(Collection **)r_value = collection;
-          },
-      };
-      return &collection_type;
+      bNodeSocketValueCollection *value = (bNodeSocketValueCollection *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.id = (ID *)value->value;
+      return IDP_New(IDP_ID, &idprop, socket.identifier);
     }
     case SOCK_TEXTURE: {
-      static const SocketPropertyType texture_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueTexture *value = (bNodeSocketValueTexture *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.id = (ID *)value->value;
-            return IDP_New(IDP_ID, &idprop, name);
-          },
-          nullptr,
-          nullptr,
-          nullptr,
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_ID; },
-          [](const IDProperty &property, void *r_value) {
-            ID *id = IDP_Id(&property);
-            Tex *texture = (id && GS(id->name) == ID_TE) ? (Tex *)id : nullptr;
-            *(Tex **)r_value = texture;
-          },
-      };
-      return &texture_type;
+      bNodeSocketValueTexture *value = (bNodeSocketValueTexture *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.id = (ID *)value->value;
+      return IDP_New(IDP_ID, &idprop, socket.identifier);
     }
     case SOCK_MATERIAL: {
-      static const SocketPropertyType material_type = {
-          [](const bNodeSocket &socket, const char *name) {
-            bNodeSocketValueMaterial *value = (bNodeSocketValueMaterial *)socket.default_value;
-            IDPropertyTemplate idprop = {0};
-            idprop.id = (ID *)value->value;
-            return IDP_New(IDP_ID, &idprop, name);
-          },
-          nullptr,
-          nullptr,
-          nullptr,
-          nullptr,
-          [](const IDProperty &property) { return property.type == IDP_ID; },
-          [](const IDProperty &property, void *r_value) {
-            ID *id = IDP_Id(&property);
-            Material *material = (id && GS(id->name) == ID_MA) ? (Material *)id : nullptr;
-            *(Material **)r_value = material;
-          },
-      };
-      return &material_type;
+      bNodeSocketValueMaterial *value = (bNodeSocketValueMaterial *)socket.default_value;
+      IDPropertyTemplate idprop = {0};
+      idprop.id = (ID *)value->value;
+      return IDP_New(IDP_ID, &idprop, socket.identifier);
+    }
+  }
+  return nullptr;
+}
+
+static bool id_property_type_matches_socket(const bNodeSocket &socket, const IDProperty &property)
+{
+  switch (socket.type) {
+    case SOCK_FLOAT:
+      return ELEM(property.type, IDP_FLOAT, IDP_DOUBLE);
+    case SOCK_INT:
+      return property.type == IDP_INT;
+    case SOCK_VECTOR:
+      return property.type == IDP_ARRAY && property.subtype == IDP_FLOAT && property.len == 3;
+    case SOCK_BOOLEAN:
+      return property.type == IDP_INT;
+    case SOCK_STRING:
+      return property.type == IDP_STRING;
+    case SOCK_OBJECT:
+    case SOCK_COLLECTION:
+    case SOCK_TEXTURE:
+    case SOCK_MATERIAL:
+      return property.type == IDP_ID;
+  }
+  BLI_assert_unreachable();
+  return false;
+}
+
+static void init_socket_cpp_value_from_property(const IDProperty &property,
+                                                const eNodeSocketDatatype socket_value_type,
+                                                void *r_value)
+{
+  switch (socket_value_type) {
+    case SOCK_FLOAT: {
+      if (property.type == IDP_FLOAT) {
+        *(float *)r_value = IDP_Float(&property);
+      }
+      else if (property.type == IDP_DOUBLE) {
+        *(float *)r_value = (float)IDP_Double(&property);
+      }
+      break;
+    }
+    case SOCK_INT: {
+      *(int *)r_value = IDP_Int(&property);
+      break;
+    }
+    case SOCK_VECTOR: {
+      copy_v3_v3((float *)r_value, (const float *)IDP_Array(&property));
+      break;
+    }
+    case SOCK_BOOLEAN: {
+      *(bool *)r_value = IDP_Int(&property) != 0;
+      break;
+    }
+    case SOCK_STRING: {
+      new (r_value) std::string(IDP_String(&property));
+      break;
+    }
+    case SOCK_OBJECT: {
+      ID *id = IDP_Id(&property);
+      Object *object = (id && GS(id->name) == ID_OB) ? (Object *)id : nullptr;
+      *(Object **)r_value = object;
+      break;
+    }
+    case SOCK_COLLECTION: {
+      ID *id = IDP_Id(&property);
+      Collection *collection = (id && GS(id->name) == ID_GR) ? (Collection *)id : nullptr;
+      *(Collection **)r_value = collection;
+      break;
+    }
+    case SOCK_TEXTURE: {
+      ID *id = IDP_Id(&property);
+      Tex *texture = (id && GS(id->name) == ID_TE) ? (Tex *)id : nullptr;
+      *(Tex **)r_value = texture;
+      break;
+    }
+    case SOCK_MATERIAL: {
+      ID *id = IDP_Id(&property);
+      Material *material = (id && GS(id->name) == ID_MA) ? (Material *)id : nullptr;
+      *(Material **)r_value = material;
+      break;
     }
     default: {
-      return nullptr;
+      BLI_assert_unreachable();
+      break;
     }
   }
 }
@@ -647,32 +477,39 @@ void MOD_nodes_update_interface(Object *object, NodesModifierData *nmd)
   }
 
   IDProperty *old_properties = nmd->settings.properties;
-
   {
     IDPropertyTemplate idprop = {0};
     nmd->settings.properties = IDP_New(IDP_GROUP, &idprop, "Nodes Modifier Settings");
   }
 
-  IDProperty *ui_container_group;
-  {
-    IDPropertyTemplate idprop = {0};
-    ui_container_group = IDP_New(IDP_GROUP, &idprop, "_RNA_UI");
-    IDP_AddToGroup(nmd->settings.properties, ui_container_group);
-  }
-
   LISTBASE_FOREACH (bNodeSocket *, socket, &nmd->node_group->inputs) {
-    const SocketPropertyType *property_type = get_socket_property_type(*socket);
-    if (property_type == nullptr) {
+    IDProperty *new_prop = id_property_create_from_socket(*socket);
+    if (new_prop == nullptr) {
+      /* Out of the set of supported input sockets, only
+       * geometry sockets aren't added to the modifier. */
+      BLI_assert(socket->type == SOCK_GEOMETRY);
       continue;
     }
 
-    IDProperty *new_prop = socket_add_property(
-        nmd->settings.properties, ui_container_group, *property_type, *socket);
+    new_prop->flag |= IDP_FLAG_OVERRIDABLE_LIBRARY;
+    if (socket->description[0] != '\0') {
+      IDPropertyUIData *ui_data = IDP_ui_data_ensure(new_prop);
+      ui_data->description = BLI_strdup(socket->description);
+    }
+    IDP_AddToGroup(nmd->settings.properties, new_prop);
 
     if (old_properties != nullptr) {
       IDProperty *old_prop = IDP_GetPropertyFromGroup(old_properties, socket->identifier);
-      if (old_prop != nullptr && property_type->is_correct_type(*old_prop)) {
+      if (old_prop != nullptr && id_property_type_matches_socket(*socket, *old_prop)) {
+        /* #IDP_CopyPropertyContent replaces the UI data as well, which we don't (we only
+         * want to replace the values). So release it temporarily and replace it after. */
+        IDPropertyUIData *ui_data = new_prop->ui_data;
+        new_prop->ui_data = nullptr;
         IDP_CopyPropertyContent(new_prop, old_prop);
+        if (new_prop->ui_data != nullptr) {
+          IDP_ui_data_free(new_prop);
+        }
+        new_prop->ui_data = ui_data;
       }
     }
   }
@@ -713,14 +550,8 @@ void MOD_nodes_init(Main *bmain, NodesModifierData *nmd)
 
 static void initialize_group_input(NodesModifierData &nmd,
                                    const bNodeSocket &socket,
-                                   const CPPType &cpp_type,
                                    void *r_value)
 {
-  const SocketPropertyType *property_type = get_socket_property_type(socket);
-  if (property_type == nullptr) {
-    cpp_type.copy_construct(cpp_type.default_value(), r_value);
-    return;
-  }
   if (nmd.settings.properties == nullptr) {
     socket.typeinfo->get_geometry_nodes_cpp_value(socket, r_value);
     return;
@@ -731,11 +562,13 @@ static void initialize_group_input(NodesModifierData &nmd,
     socket.typeinfo->get_geometry_nodes_cpp_value(socket, r_value);
     return;
   }
-  if (!property_type->is_correct_type(*property)) {
+  if (!id_property_type_matches_socket(socket, *property)) {
     socket.typeinfo->get_geometry_nodes_cpp_value(socket, r_value);
     return;
   }
-  property_type->init_cpp_value(*property, r_value);
+
+  init_socket_cpp_value_from_property(
+      *property, static_cast<eNodeSocketDatatype>(socket.type), r_value);
 }
 
 static Vector<SpaceSpreadsheet *> find_spreadsheet_editors(Main *bmain)
@@ -886,7 +719,7 @@ static GeometrySet compute_geometry(const DerivedNodeTree &tree,
     for (const OutputSocketRef *socket : remaining_input_sockets) {
       const CPPType &cpp_type = *socket->typeinfo()->get_geometry_nodes_cpp_type();
       void *value_in = allocator.allocate(cpp_type.size(), cpp_type.alignment());
-      initialize_group_input(*nmd, *socket->bsocket(), cpp_type, value_in);
+      initialize_group_input(*nmd, *socket->bsocket(), value_in);
       group_inputs.add_new({root_context, socket}, {cpp_type, value_in});
     }
   }
@@ -954,8 +787,7 @@ static void check_property_socket_sync(const Object *ob, ModifierData *md)
       continue;
     }
 
-    const SocketPropertyType *property_type = get_socket_property_type(*socket);
-    if (!property_type->is_correct_type(*property)) {
+    if (!id_property_type_matches_socket(*socket, *property)) {
       BKE_modifier_set_error(
           ob, md, "Property type does not match input socket \"(%s)\"", socket->name);
       continue;
@@ -1051,17 +883,12 @@ static void draw_property_for_socket(uiLayout *layout,
                                      const IDProperty *modifier_props,
                                      const bNodeSocket &socket)
 {
-  const SocketPropertyType *property_type = get_socket_property_type(socket);
-  if (property_type == nullptr) {
-    return;
-  }
-
   /* The property should be created in #MOD_nodes_update_interface with the correct type. */
   IDProperty *property = IDP_GetPropertyFromGroup(modifier_props, socket.identifier);
 
   /* IDProperties can be removed with python, so there could be a situation where
    * there isn't a property for a socket or it doesn't have the correct type. */
-  if (property == nullptr || !property_type->is_correct_type(*property)) {
+  if (property == nullptr || !id_property_type_matches_socket(socket, *property)) {
     return;
   }
 
diff --git a/source/blender/python/generic/CMakeLists.txt b/source/blender/python/generic/CMakeLists.txt
index dce6a7e1c91..10cc1e8b113 100644
--- a/source/blender/python/generic/CMakeLists.txt
+++ b/source/blender/python/generic/CMakeLists.txt
@@ -21,6 +21,7 @@ set(INC
   ../../blenlib
   ../../gpu
   ../../makesdna
+  ../../makesrna
   ../../../../intern/glew-mx
   ../../../../intern/guardedalloc
 )
@@ -36,6 +37,7 @@ set(SRC
   blf_py_api.c
   bpy_threads.c
   idprop_py_api.c
+  idprop_py_ui_api.c
   imbuf_py_api.c
   py_capi_utils.c
 
@@ -43,6 +45,7 @@ set(SRC
   bl_math_py_api.h
   blf_py_api.h
   idprop_py_api.h
+  idprop_py_ui_api.h
   imbuf_py_api.h
   py_capi_utils.h
 
diff --git a/source/blender/python/generic/idprop_py_api.c b/source/blender/python/generic/idprop_py_api.c
index 024900db691..58a947943b1 100644
--- a/source/blender/python/generic/idprop_py_api.c
+++ b/source/blender/python/generic/idprop_py_api.c
@@ -25,6 +25,7 @@
 #include "BLI_utildefines.h"
 
 #include "idprop_py_api.h"
+#include "idprop_py_ui_api.h"
 
 #include "BKE_idprop.h"
 
@@ -2135,6 +2136,7 @@ static PyObject *BPyInit_idprop_types(void)
   submodule = PyModule_Create(&IDProp_types_module_def);
 
   IDProp_Init_Types();
+  IDPropertyUIData_Init_Types();
 
   /* bmesh_py_types.c */
   PyModule_AddType(submodule, &BPy_IDGroup_Type);
diff --git a/source/blender/python/generic/idprop_py_ui_api.c b/source/blender/python/generic/idprop_py_ui_api.c
new file mode 100644
index 00000000000..92cc3b8e1dd
--- /dev/null
+++ b/source/blender/python/generic/idprop_py_ui_api.c
@@ -0,0 +1,734 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/** \file
+ * \ingroup pygen
+ */
+
+#include <Python.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_string.h"
+#include "BLI_utildefines.h"
+
+#include "idprop_py_ui_api.h"
+
+#include "BKE_idprop.h"
+
+#include "DNA_ID.h"
+
+#include "RNA_access.h"
+#include "RNA_enum_types.h"
+
+#include "../intern/bpy_rna.h"
+
+#define USE_STRING_COERCE
+
+#ifdef USE_STRING_COERCE
+#  include "py_capi_utils.h"
+#endif
+
+#include "python_utildefines.h"
+
+/* -------------------------------------------------------------------- */
+/** \name UI Data Update
+ * \{ */
+
+static bool args_contain_key(PyObject *kwargs, const char *name)
+{
+  PyObject *py_key = PyUnicode_FromString(name);
+  const bool result = PyDict_Contains(kwargs, py_key) == 1;
+  Py_DECREF(py_key);
+  return result;
+}
+
+/**
+ * \return False when parsing fails, in which case caller should return NULL.
+ */
+static bool idprop_ui_data_update_base(IDPropertyUIData *ui_data,
+                                       const char *rna_subtype,
+                                       const char *description)
+{
+  if (rna_subtype != NULL) {
+    if (pyrna_enum_value_from_id(rna_enum_property_subtype_items,
+                                 rna_subtype,
+                                 &ui_data->rna_subtype,
+                                 "IDPropertyUIManager.update") == -1) {
+      return false;
+    }
+  }
+
+  if (description != NULL) {
+    ui_data->description = BLI_strdup(description);
+  }
+
+  return true;
+}
+
+/**
+ * \note The default value needs special handling because for array IDProperties it can
+ * be a single value or an array, but for non-array properties it can only be a value.
+ */
+static bool idprop_ui_data_update_int_default(IDProperty *idprop,
+                                              IDPropertyUIDataInt *ui_data,
+                                              PyObject *default_value)
+{
+  if (PySequence_Check(default_value)) {
+    if (idprop->type != IDP_ARRAY) {
+      PyErr_SetString(PyExc_TypeError, "Only array properties can have array default values");
+      return false;
+    }
+
+    Py_ssize_t len = PySequence_Size(default_value);
+    int *new_default_array = (int *)MEM_malloc_arrayN(len, sizeof(int), __func__);
+    if (PyC_AsArray(
+            new_default_array, sizeof(int), default_value, len, &PyLong_Type, "ui_data_update") ==
+        -1) {
+      MEM_freeN(new_default_array);
+      return false;
+    }
+
+    ui_data->default_array_len = len;
+    ui_data->default_array = new_default_array;
+  }
+  else {
+    const int value = PyC_Long_AsI32(default_value);
+    if ((value == -1) && PyErr_Occurred()) {
+      PyErr_SetString(PyExc_ValueError, "Error converting \"default\" argument to integer");
+      return false;
+    }
+    ui_data->default_value = value;
+  }
+
+  return true;
+}
+
+/**
+ * \return False when parsing fails, in which case caller should return NULL.
+ */
+static bool idprop_ui_data_update_int(IDProperty *idprop, PyObject *args, PyObject *kwargs)
+{
+  const char *rna_subtype = NULL;
+  const char *description = NULL;
+  int min, max, soft_min, soft_max, step;
+  PyObject *default_value = NULL;
+  const char *kwlist[] = {
+      "min", "max", "soft_min", "soft_max", "step", "default", "subtype", "description", NULL};
+  if (!PyArg_ParseTupleAndKeywords(args,
+                                   kwargs,
+                                   "|$iiiiiOzz:update",
+                                   (char **)kwlist,
+                                   &min,
+                                   &max,
+                                   &soft_min,
+                                   &soft_max,
+                                   &step,
+                                   &default_value,
+                                   &rna_subtype,
+                                   &description)) {
+    return false;
+  }
+
+  /* Write to a temporary copy of the UI data in case some part of the parsing fails. */
+  IDPropertyUIDataInt *ui_data_orig = (IDPropertyUIDataInt *)idprop->ui_data;
+  IDPropertyUIDataInt ui_data = *ui_data_orig;
+
+  if (!idprop_ui_data_update_base(&ui_data.base, rna_subtype, description)) {
+    IDP_ui_data_free_unique_contents(&ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+    return false;
+  }
+
+  if (args_contain_key(kwargs, "min")) {
+    ui_data.min = min;
+    ui_data.soft_min = MAX2(ui_data.soft_min, ui_data.min);
+    ui_data.max = MAX2(ui_data.min, ui_data.max);
+  }
+  if (args_contain_key(kwargs, "max")) {
+    ui_data.max = max;
+    ui_data.soft_max = MIN2(ui_data.soft_max, ui_data.max);
+    ui_data.min = MIN2(ui_data.min, ui_data.max);
+  }
+  if (args_contain_key(kwargs, "soft_min")) {
+    ui_data.soft_min = soft_min;
+    ui_data.soft_min = MAX2(ui_data.soft_min, ui_data.min);
+    ui_data.soft_max = MAX2(ui_data.soft_min, ui_data.soft_max);
+  }
+  if (args_contain_key(kwargs, "soft_max")) {
+    ui_data.soft_max = soft_max;
+    ui_data.soft_max = MIN2(ui_data.soft_max, ui_data.max);
+    ui_data.soft_min = MIN2(ui_data.soft_min, ui_data.soft_max);
+  }
+  if (args_contain_key(kwargs, "step")) {
+    ui_data.step = step;
+  }
+
+  if (!ELEM(default_value, NULL, Py_None)) {
+    if (!idprop_ui_data_update_int_default(idprop, &ui_data, default_value)) {
+      IDP_ui_data_free_unique_contents(
+          &ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+      return false;
+    }
+  }
+
+  /* Write back to the proeprty's UI data. */
+  IDP_ui_data_free_unique_contents(&ui_data_orig->base, IDP_ui_data_type(idprop), &ui_data.base);
+  *ui_data_orig = ui_data;
+  return true;
+}
+
+/**
+ * \note The default value needs special handling because for array IDProperties it can
+ * be a single value or an array, but for non-array properties it can only be a value.
+ */
+static bool idprop_ui_data_update_float_default(IDProperty *idprop,
+                                                IDPropertyUIDataFloat *ui_data,
+                                                PyObject *default_value)
+{
+  if (PySequence_Check(default_value)) {
+    if (idprop->type != IDP_ARRAY) {
+      PyErr_SetString(PyExc_TypeError, "Only array properties can have array default values");
+      return false;
+    }
+
+    Py_ssize_t len = PySequence_Size(default_value);
+    double *new_default_array = (double *)MEM_malloc_arrayN(len, sizeof(double), __func__);
+    if (PyC_AsArray(new_default_array,
+                    sizeof(double),
+                    default_value,
+                    len,
+                    &PyFloat_Type,
+                    "ui_data_update") == -1) {
+      MEM_freeN(new_default_array);
+      return false;
+    }
+
+    ui_data->default_array_len = len;
+    ui_data->default_array = new_default_array;
+  }
+  else {
+    const double value = PyFloat_AsDouble(default_value);
+    if ((value == -1.0) && PyErr_Occurred()) {
+      PyErr_SetString(PyExc_ValueError, "Error converting \"default\" argument to double");
+      return false;
+    }
+    ui_data->default_value = value;
+  }
+
+  return true;
+}
+
+/**
+ * \return False when parsing fails, in which case caller should return NULL.
+ */
+static bool idprop_ui_data_update_float(IDProperty *idprop, PyObject *args, PyObject *kwargs)
+{
+  const char *rna_subtype = NULL;
+  const char *description = NULL;
+  int precision;
+  double min, max, soft_min, soft_max, step;
+  PyObject *default_value = NULL;
+  const char *kwlist[] = {"min",
+                          "max",
+                          "soft_min",
+                          "soft_max",
+                          "step",
+                          "precision",
+                          "default",
+                          "subtype",
+                          "description",
+                          NULL};
+  if (!PyArg_ParseTupleAndKeywords(args,
+                                   kwargs,
+                                   "|$dddddiOzz:update",
+                                   (char **)kwlist,
+                                   &min,
+                                   &max,
+                                   &soft_min,
+                                   &soft_max,
+                                   &step,
+                                   &precision,
+                                   &default_value,
+                                   &rna_subtype,
+                                   &description)) {
+    return false;
+  }
+
+  /* Write to a temporary copy of the UI data in case some part of the parsing fails. */
+  IDPropertyUIDataFloat *ui_data_orig = (IDPropertyUIDataFloat *)idprop->ui_data;
+  IDPropertyUIDataFloat ui_data = *ui_data_orig;
+
+  if (!idprop_ui_data_update_base(&ui_data.base, rna_subtype, description)) {
+    IDP_ui_data_free_unique_contents(&ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+    return false;
+  }
+
+  if (args_contain_key(kwargs, "min")) {
+    ui_data.min = min;
+    ui_data.soft_min = MAX2(ui_data.soft_min, ui_data.min);
+    ui_data.max = MAX2(ui_data.min, ui_data.max);
+  }
+  if (args_contain_key(kwargs, "max")) {
+    ui_data.max = max;
+    ui_data.soft_max = MIN2(ui_data.soft_max, ui_data.max);
+    ui_data.min = MIN2(ui_data.min, ui_data.max);
+  }
+  if (args_contain_key(kwargs, "soft_min")) {
+    ui_data.soft_min = soft_min;
+    ui_data.soft_min = MAX2(ui_data.soft_min, ui_data.min);
+    ui_data.soft_max = MAX2(ui_data.soft_min, ui_data.soft_max);
+  }
+  if (args_contain_key(kwargs, "soft_max")) {
+    ui_data.soft_max = soft_max;
+    ui_data.soft_max = MIN2(ui_data.soft_max, ui_data.max);
+    ui_data.soft_min = MIN2(ui_data.soft_min, ui_data.soft_max);
+  }
+  if (args_contain_key(kwargs, "step")) {
+    ui_data.step = (float)step;
+  }
+  if (args_contain_key(kwargs, "precision")) {
+    ui_data.precision = precision;
+  }
+
+  if (!ELEM(default_value, NULL, Py_None)) {
+    if (!idprop_ui_data_update_float_default(idprop, &ui_data, default_value)) {
+      IDP_ui_data_free_unique_contents(
+          &ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+      return false;
+    }
+  }
+
+  /* Write back to the proeprty's UI data. */
+  IDP_ui_data_free_unique_contents(&ui_data_orig->base, IDP_ui_data_type(idprop), &ui_data.base);
+  *ui_data_orig = ui_data;
+  return true;
+}
+
+/**
+ * \return False when parsing fails, in which case caller should return NULL.
+ */
+static bool idprop_ui_data_update_string(IDProperty *idprop, PyObject *args, PyObject *kwargs)
+{
+  const char *rna_subtype = NULL;
+  const char *description = NULL;
+  const char *default_value;
+  const char *kwlist[] = {"default", "subtype", "description", NULL};
+  if (!PyArg_ParseTupleAndKeywords(args,
+                                   kwargs,
+                                   "|$zzz:update",
+                                   (char **)kwlist,
+                                   &default_value,
+                                   &rna_subtype,
+                                   &description)) {
+    return false;
+  }
+
+  /* Write to a temporary copy of the UI data in case some part of the parsing fails. */
+  IDPropertyUIDataString *ui_data_orig = (IDPropertyUIDataString *)idprop->ui_data;
+  IDPropertyUIDataString ui_data = *ui_data_orig;
+
+  if (!idprop_ui_data_update_base(&ui_data.base, rna_subtype, description)) {
+    IDP_ui_data_free_unique_contents(&ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+    return false;
+  }
+
+  if (default_value != NULL) {
+    ui_data.default_value = BLI_strdup(default_value);
+  }
+
+  /* Write back to the proeprty's UI data. */
+  IDP_ui_data_free_unique_contents(&ui_data_orig->base, IDP_ui_data_type(idprop), &ui_data.base);
+  *ui_data_orig = ui_data;
+  return true;
+}
+
+/**
+ * \return False when parsing fails, in which case caller should return NULL.
+ */
+static bool idprop_ui_data_update_id(IDProperty *idprop, PyObject *args, PyObject *kwargs)
+{
+  const char *rna_subtype = NULL;
+  const char *description = NULL;
+  const char *kwlist[] = {"subtype", "description", NULL};
+  if (!PyArg_ParseTupleAndKeywords(
+          args, kwargs, "|$zz:update", (char **)kwlist, &rna_subtype, &description)) {
+    return false;
+  }
+
+  /* Write to a temporary copy of the UI data in case some part of the parsing fails. */
+  IDPropertyUIDataID *ui_data_orig = (IDPropertyUIDataID *)idprop->ui_data;
+  IDPropertyUIDataID ui_data = *ui_data_orig;
+
+  if (!idprop_ui_data_update_base(&ui_data.base, rna_subtype, description)) {
+    IDP_ui_data_free_unique_contents(&ui_data.base, IDP_ui_data_type(idprop), &ui_data_orig->base);
+    return false;
+  }
+
+  /* Write back to the proeprty's UI data. */
+  IDP_ui_data_free_unique_contents(&ui_data_orig->base, IDP_ui_data_type(idprop), &ui_data.base);
+  *ui_data_orig = ui_data;
+  return true;
+}
+
+PyDoc_STRVAR(BPy_IDPropertyUIManager_update_doc,
+             ".. method:: update( "
+             "subtype=None, "
+             "min=None, "
+             "max=None, "
+             "soft_min=None, "
+             "soft_max=None, "
+             "precision=None, "
+             "step=None, "
+             "default=None, "
+             "description=None)\n"
+             "\n"
+             "   Update the RNA information of the IDProperty used for interaction and\n"
+             "   display in the user interface. The required types for many of the keyword\n"
+             "   arguments depend on the type of the property.\n ");
+static PyObject *BPy_IDPropertyUIManager_update(BPy_IDPropertyUIManager *self,
+                                                PyObject *args,
+                                                PyObject *kwargs)
+{
+  IDProperty *property = self->property;
+  BLI_assert(IDP_ui_data_supported(property));
+
+  switch (IDP_ui_data_type(property)) {
+    case IDP_UI_DATA_TYPE_INT:
+      IDP_ui_data_ensure(property);
+      if (!idprop_ui_data_update_int(property, args, kwargs)) {
+        return NULL;
+      }
+      Py_RETURN_NONE;
+    case IDP_UI_DATA_TYPE_FLOAT:
+      IDP_ui_data_ensure(property);
+      if (!idprop_ui_data_update_float(property, args, kwargs)) {
+        return NULL;
+      }
+      Py_RETURN_NONE;
+    case IDP_UI_DATA_TYPE_STRING:
+      IDP_ui_data_ensure(property);
+      if (!idprop_ui_data_update_string(property, args, kwargs)) {
+        return NULL;
+      }
+      Py_RETURN_NONE;
+    case IDP_UI_DATA_TYPE_ID:
+      IDP_ui_data_ensure(property);
+      if (!idprop_ui_data_update_id(property, args, kwargs)) {
+        return NULL;
+      }
+      Py_RETURN_NONE;
+    case IDP_UI_DATA_TYPE_UNSUPPORTED:
+      PyErr_Format(PyExc_TypeError, "IDProperty \"%s\" does not support RNA data", property->name);
+      return NULL;
+  }
+
+  BLI_assert_unreachable();
+  Py_RETURN_NONE;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name UI Data As Dictionary
+ * \{ */
+
+static void idprop_ui_data_to_dict_int(IDProperty *property, PyObject *dict)
+{
+  IDPropertyUIDataInt *ui_data = (IDPropertyUIDataInt *)property->ui_data;
+  PyObject *item;
+
+  PyDict_SetItemString(dict, "min", item = PyLong_FromLong(ui_data->min));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "max", item = PyLong_FromLong(ui_data->max));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "soft_min", item = PyLong_FromLong(ui_data->soft_min));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "soft_max", item = PyLong_FromLong(ui_data->soft_max));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "step", item = PyLong_FromLong(ui_data->step));
+  Py_DECREF(item);
+  if (property->type == IDP_ARRAY) {
+    PyObject *list = PyList_New(ui_data->default_array_len);
+    for (int i = 0; i < ui_data->default_array_len; i++) {
+      PyList_SET_ITEM(list, i, PyLong_FromLong(ui_data->default_array[i]));
+    }
+    PyDict_SetItemString(dict, "default", list);
+    Py_DECREF(list);
+  }
+  else {
+    PyDict_SetItemString(dict, "default", item = PyLong_FromLong(ui_data->step));
+    Py_DECREF(item);
+  }
+}
+
+static void idprop_ui_data_to_dict_float(IDProperty *property, PyObject *dict)
+{
+  IDPropertyUIDataFloat *ui_data = (IDPropertyUIDataFloat *)property->ui_data;
+  PyObject *item;
+
+  PyDict_SetItemString(dict, "min", item = PyFloat_FromDouble(ui_data->min));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "max", item = PyFloat_FromDouble(ui_data->max));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "soft_min", item = PyFloat_FromDouble(ui_data->soft_min));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "soft_max", item = PyFloat_FromDouble(ui_data->soft_max));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "step", item = PyFloat_FromDouble((double)ui_data->step));
+  Py_DECREF(item);
+  PyDict_SetItemString(dict, "precision", item = PyFloat_FromDouble((double)ui_data->precision));
+  Py_DECREF(item);
+  if (property->type == IDP_ARRAY) {
+    PyObject *list = PyList_New(ui_data->default_array_len);
+    for (int i = 0; i < ui_data->default_array_len; i++) {
+      PyList_SET_ITEM(list, i, PyFloat_FromDouble(ui_data->default_array[i]));
+    }
+    PyDict_SetItemString(dict, "default", list);
+    Py_DECREF(list);
+  }
+  else {
+    PyDict_SetItemString(dict, "default", item = PyFloat_FromDouble(ui_data->step));
+    Py_DECREF(item);
+  }
+}
+
+static void idprop_ui_data_to_dict_string(IDProperty *property, PyObject *dict)
+{
+  IDPropertyUIDataString *ui_data = (IDPropertyUIDataString *)property->ui_data;
+  PyObject *item;
+
+  const char *default_value = (ui_data->default_value == NULL) ? "" : ui_data->default_value;
+
+  PyDict_SetItemString(dict, "default", item = PyUnicode_FromString(default_value));
+  Py_DECREF(item);
+}
+
+PyDoc_STRVAR(BPy_IDPropertyUIManager_as_dict_doc,
+             ".. method:: as_dict()\n"
+             "\n"
+             "   Return a dictionary of the property's RNA UI data. The fields in the\n"
+             "   returned dictionary and their types will depend on the property's type.\n");
+static PyObject *BPy_IDIDPropertyUIManager_as_dict(BPy_IDPropertyUIManager *self)
+{
+  IDProperty *property = self->property;
+  BLI_assert(IDP_ui_data_supported(property));
+
+  IDPropertyUIData *ui_data = IDP_ui_data_ensure(property);
+
+  PyObject *dict = PyDict_New();
+
+  /* RNA subtype. */
+  {
+    const char *subtype_id = NULL;
+    RNA_enum_identifier(rna_enum_property_subtype_items, ui_data->rna_subtype, &subtype_id);
+    PyObject *item = PyUnicode_FromString(subtype_id);
+    PyDict_SetItemString(dict, "subtype", item);
+    Py_DECREF(item);
+  }
+
+  /* Description. */
+  if (ui_data->description != NULL) {
+    PyObject *item = PyUnicode_FromString(ui_data->description);
+    PyDict_SetItemString(dict, "description", item);
+    Py_DECREF(item);
+  }
+
+  /* Type specific data. */
+  switch (IDP_ui_data_type(property)) {
+    case IDP_UI_DATA_TYPE_STRING:
+      idprop_ui_data_to_dict_string(property, dict);
+      break;
+    case IDP_UI_DATA_TYPE_ID:
+      break;
+    case IDP_UI_DATA_TYPE_INT:
+      idprop_ui_data_to_dict_int(property, dict);
+      break;
+    case IDP_UI_DATA_TYPE_FLOAT:
+      idprop_ui_data_to_dict_float(property, dict);
+      break;
+    case IDP_UI_DATA_TYPE_UNSUPPORTED:
+      BLI_assert_unreachable();
+      break;
+  }
+
+  return dict;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name UI Data Clear
+ * \{ */
+
+PyDoc_STRVAR(BPy_IDPropertyUIManager_clear_doc,
+             ".. method:: clear()\n"
+             "\n"
+             "   Remove the RNA UI data from this IDProperty.\n");
+static PyObject *BPy_IDPropertyUIManager_clear(BPy_IDPropertyUIManager *self)
+{
+  IDProperty *property = self->property;
+  BLI_assert(IDP_ui_data_supported(property));
+
+  if (property == NULL) {
+    PyErr_SetString(PyExc_RuntimeError, "IDPropertyUIManager missing property");
+    BLI_assert_unreachable();
+    return NULL;
+  }
+
+  if (property->ui_data != NULL) {
+    IDP_ui_data_free(property);
+  }
+
+  Py_RETURN_NONE;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name UI Data Copying
+ * \{ */
+
+PyDoc_STRVAR(
+    BPy_IDPropertyUIManager_update_from_doc,
+    ".. method:: update_from(ui_manager_source)\n"
+    "\n"
+    "   Copy UI data from an IDProperty in the source group to a property in this group.\n "
+    "   If the source property has no UI data, the target UI data will be reset if it exists.\n"
+    "\n"
+    "   :raises TypeError: If the types of the two properties don't match.\n");
+static PyObject *BPy_IDPropertyUIManager_update_from(BPy_IDPropertyUIManager *self, PyObject *args)
+{
+  IDProperty *property = self->property;
+  BLI_assert(IDP_ui_data_supported(property));
+
+  BPy_IDPropertyUIManager *ui_manager_src;
+  if (!PyArg_ParseTuple(args, "O!:update_from", &BPy_IDPropertyUIManager_Type, &ui_manager_src)) {
+    return NULL;
+  }
+
+  if (property->ui_data != NULL) {
+    IDP_ui_data_free(property);
+  }
+
+  property->ui_data = IDP_ui_data_copy(ui_manager_src->property);
+
+  Py_RETURN_NONE;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name UI Data Manager Definition
+ * \{ */
+
+static struct PyMethodDef BPy_IDPropertyUIManager_methods[] = {
+    {"update",
+     (PyCFunction)BPy_IDPropertyUIManager_update,
+     METH_VARARGS | METH_KEYWORDS,
+     BPy_IDPropertyUIManager_update_doc},
+    {"as_dict",
+     (PyCFunction)BPy_IDIDPropertyUIManager_as_dict,
+     METH_NOARGS,
+     BPy_IDPropertyUIManager_as_dict_doc},
+    {"clear",
+     (PyCFunction)BPy_IDPropertyUIManager_clear,
+     METH_NOARGS,
+     BPy_IDPropertyUIManager_clear_doc},
+    {"update_from",
+     (PyCFunction)BPy_IDPropertyUIManager_update_from,
+     METH_VARARGS,
+     BPy_IDPropertyUIManager_update_from_doc},
+    {NULL, NULL, 0, NULL},
+};
+
+static PyObject *BPy_IDPropertyUIManager_repr(BPy_IDPropertyUIManager *self)
+{
+  return PyUnicode_FromFormat(
+      "<bpy id prop ui manager: name=\"%s\", address=%p>", self->property->name, self->property);
+}
+
+static Py_hash_t BPy_IDPropertyUIManager_hash(BPy_IDPropertyUIManager *self)
+{
+  return _Py_HashPointer(self->property);
+}
+
+PyTypeObject BPy_IDPropertyUIManager_Type = {
+    PyVarObject_HEAD_INIT(NULL, 0)
+    /*  For printing, in format "<module>.<name>" */
+    "IDPropertyUIManager",           /* char *tp_name; */
+    sizeof(BPy_IDPropertyUIManager), /* int tp_basicsize; */
+    0,                               /* tp_itemsize;  For allocation */
+
+    /* Methods to implement standard operations */
+
+    NULL,                                   /* destructor tp_dealloc; */
+    0,                                      /* tp_vectorcall_offset */
+    NULL,                                   /* getattrfunc tp_getattr; */
+    NULL,                                   /* setattrfunc tp_setattr; */
+    NULL,                                   /* cmpfunc tp_compare; */
+    (reprfunc)BPy_IDPropertyUIManager_repr, /* reprfunc tp_repr; */
+
+    /* Method suites for standard classes */
+
+    NULL, /* PyNumberMethods *tp_as_number; */
+    NULL, /* PySequenceMethods *tp_as_sequence; */
+    NULL, /* PyMappingMethods *tp_as_mapping; */
+
+    /* More standard operations (here for binary compatibility) */
+
+    (hashfunc)BPy_IDPropertyUIManager_hash, /* hashfunc tp_hash; */
+    NULL,                                   /* ternaryfunc tp_call; */
+    NULL,                                   /* reprfunc tp_str; */
+    NULL,                                   /* getattrofunc tp_getattro; */
+    NULL,                                   /* setattrofunc tp_setattro; */
+
+    /* Functions to access object as input/output buffer */
+    NULL, /* PyBufferProcs *tp_as_buffer; */
+
+    /*** Flags to define presence of optional/expanded features ***/
+    Py_TPFLAGS_DEFAULT, /* long tp_flags; */
+
+    NULL, /*  char *tp_doc;  Documentation string */
+    /*** Assigned meaning in release 2.0 ***/
+    /* call function for all accessible objects */
+    NULL, /* traverseproc tp_traverse; */
+
+    /* delete references to contained objects */
+    NULL, /* inquiry tp_clear; */
+
+    /***  Assigned meaning in release 2.1 ***/
+    /*** rich comparisons ***/
+    NULL, /* richcmpfunc tp_richcompare; */
+
+    /***  weak reference enabler ***/
+    0, /* long tp_weaklistoffset; */
+
+    /*** Added in release 2.2 ***/
+    /*   Iterators */
+    NULL, /* getiterfunc tp_iter; */
+    NULL, /* iternextfunc tp_iternext; */
+    /*** Attribute descriptor and subclassing stuff ***/
+    BPy_IDPropertyUIManager_methods, /* struct PyMethodDef *tp_methods; */
+    NULL,                            /* struct PyMemberDef *tp_members; */
+    NULL,                            /* struct PyGetSetDef *tp_getset; */
+};
+
+void IDPropertyUIData_Init_Types()
+{
+  PyType_Ready(&BPy_IDPropertyUIManager_Type);
+}
+
+/** \} */
diff --git a/source/blender/python/generic/idprop_py_ui_api.h b/source/blender/python/generic/idprop_py_ui_api.h
new file mode 100644
index 00000000000..f678e5ae9c1
--- /dev/null
+++ b/source/blender/python/generic/idprop_py_ui_api.h
@@ -0,0 +1,33 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/** \file
+ * \ingroup pygen
+ */
+
+#pragma once
+
+struct ID;
+struct IDProperty;
+
+extern PyTypeObject BPy_IDPropertyUIManager_Type;
+
+typedef struct BPy_IDPropertyUIManager {
+  PyObject_VAR_HEAD
+  struct IDProperty *property;
+} BPy_IDPropertyUIManager;
+
+void IDPropertyUIData_Init_Types(void);
diff --git a/source/blender/python/intern/bpy.c b/source/blender/python/intern/bpy.c
index 0e0f431cb19..7646109c1b0 100644
--- a/source/blender/python/intern/bpy.c
+++ b/source/blender/python/intern/bpy.c
@@ -56,6 +56,7 @@
 
 /* external util modules */
 #include "../generic/idprop_py_api.h"
+#include "../generic/idprop_py_ui_api.h"
 #include "bpy_msgbus.h"
 
 #ifdef WITH_FREESTYLE
@@ -407,6 +408,7 @@ void BPy_init_modules(struct bContext *C)
   }
   /* stand alone utility modules not related to blender directly */
   IDProp_Init_Types(); /* not actually a submodule, just types */
+  IDPropertyUIData_Init_Types();
 #ifdef WITH_FREESTYLE
   Freestyle_Init();
 #endif
diff --git a/source/blender/python/intern/bpy_rna.c b/source/blender/python/intern/bpy_rna.c
index e9d5ae278bb..ac1fdeb2bad 100644
--- a/source/blender/python/intern/bpy_rna.c
+++ b/source/blender/python/intern/bpy_rna.c
@@ -73,6 +73,7 @@
 #include "DEG_depsgraph_query.h"
 
 #include "../generic/idprop_py_api.h" /* For IDprop lookups. */
+#include "../generic/idprop_py_ui_api.h"
 #include "../generic/py_capi_utils.h"
 #include "../generic/python_utildefines.h"
 
@@ -4309,6 +4310,51 @@ static PyObject *pyrna_struct_id_properties_ensure(BPy_StructRNA *self)
   return (PyObject *)group;
 }
 
+PyDoc_STRVAR(pyrna_struct_id_properties_ui_doc,
+             ".. method:: id_properties_ui(key)\n"
+             "\n"
+             "   :return: Return an object used to manage an IDProperty's UI data.\n"
+             "   :arg key: String name of the property.\n"
+             "   :rtype: :class:`bpy.types.IDPropertyUIManager`\n");
+static PyObject *pyrna_struct_id_properties_ui(BPy_StructRNA *self, PyObject *args)
+{
+  PYRNA_STRUCT_CHECK_OBJ(self);
+
+  if (RNA_struct_idprops_check(self->ptr.type) == 0) {
+    PyErr_SetString(PyExc_TypeError, "This type doesn't support IDProperties");
+    return NULL;
+  }
+
+  const char *key;
+  if (!PyArg_ParseTuple(args, "s:ui_data", &key)) {
+    return NULL;
+  }
+
+  IDProperty *parent_group = RNA_struct_idprops(&self->ptr, true);
+
+  /* This is a paranoid check that theoretically might not be necessary.
+   * It allows the possibility that some structs can't ensure IDProperties. */
+  if (parent_group == NULL) {
+    return Py_None;
+  }
+
+  IDProperty *property = IDP_GetPropertyFromGroup(parent_group, key);
+  if (property == NULL) {
+    PyErr_SetString(PyExc_KeyError, "Property not found in IDProperty group");
+    return NULL;
+  }
+
+  if (!IDP_ui_data_supported(property)) {
+    PyErr_Format(PyExc_TypeError, "IDProperty \"%s\" does not support UI data", property->name);
+    return NULL;
+  }
+
+  BPy_IDPropertyUIManager *ui_manager = PyObject_New(BPy_IDPropertyUIManager,
+                                                     &BPy_IDPropertyUIManager_Type);
+  ui_manager->property = property;
+  return (PyObject *)ui_manager;
+}
+
 PyDoc_STRVAR(pyrna_struct_id_properties_clear_doc,
              ".. method:: id_properties_clear()\n\n"
              "   :return: Remove the parent group for an RNA struct's custom IDProperties.\n");
@@ -5829,6 +5875,10 @@ static struct PyMethodDef pyrna_struct_methods[] = {
      (PyCFunction)pyrna_struct_id_properties_clear,
      METH_NOARGS,
      pyrna_struct_id_properties_clear_doc},
+    {"id_properties_ui",
+     (PyCFunction)pyrna_struct_id_properties_ui,
+     METH_VARARGS,
+     pyrna_struct_id_properties_ui_doc},
 
 /* experimental */
 /* unused for now */
diff --git a/tests/python/bl_pyapi_idprop.py b/tests/python/bl_pyapi_idprop.py
index 38cd9d04a6b..bdf625c1c2e 100644
--- a/tests/python/bl_pyapi_idprop.py
+++ b/tests/python/bl_pyapi_idprop.py
@@ -246,6 +246,69 @@ class TestBufferProtocol(TestHelper, unittest.TestCase):
         self.assertEqual(list(view1), list(view2))
         self.assertEqual(view1.tobytes(), view2.tobytes())
 
+class TestRNAData(TestHelper, unittest.TestCase):
+
+    def test_custom_properties_none(self):
+        bpy.data.objects.new("test", None)
+        test_object = bpy.data.objects["test"]
+
+        # Access default RNA data values.
+        test_object.id_properties_clear()
+        test_object["test_prop"] = 0.5
+        ui_data_test_prop = test_object.id_properties_ui("test_prop")
+
+        rna_data = ui_data_test_prop.as_dict()
+        self.assertTrue("min" in rna_data)
+        self.assertLess(rna_data["min"], -10000.0)
+        self.assertEqual(rna_data["subtype"], "NONE")
+        self.assertGreater(rna_data["soft_max"], 10000.0)
+
+        # Change RNA data values.
+        ui_data_test_prop.update(subtype="TEMPERATURE", min=0, soft_min=0.1)
+        rna_data = ui_data_test_prop.as_dict()
+        self.assertEqual(rna_data["min"], 0)
+        self.assertEqual(rna_data["soft_min"], 0.1)
+        self.assertEqual(rna_data["subtype"], "TEMPERATURE")
+
+        # Copy RNA data values from one property to another.
+        test_object["test_prop_2"] = 11.7
+        ui_data_test_prop_2 = test_object.id_properties_ui("test_prop_2")
+        ui_data_test_prop_2.update_from(ui_data_test_prop)
+        rna_data = ui_data_test_prop_2.as_dict()
+        self.assertEqual(rna_data["min"], 0)
+        self.assertEqual(rna_data["soft_min"], 0.1)
+        self.assertEqual(rna_data["subtype"], "TEMPERATURE")
+        self.assertGreater(rna_data["soft_max"], 10000.0)
+
+        # Copy RNA data values to another object's property.
+        bpy.data.objects.new("test_2", None)
+        test_object_2 = bpy.data.objects["test_2"]
+        test_object_2["test_prop_3"] = 20.1
+        ui_data_test_prop_3 = test_object_2.id_properties_ui("test_prop_3")
+        ui_data_test_prop_3.update_from(ui_data_test_prop_2)
+        rna_data = ui_data_test_prop_3.as_dict()
+        self.assertEqual(rna_data["min"], 0)
+        self.assertEqual(rna_data["soft_min"], 0.1)
+        self.assertEqual(rna_data["subtype"], "TEMPERATURE")
+        self.assertGreater(rna_data["soft_max"], 10000.0)
+
+        # Test RNA data for string property.
+        test_object.id_properties_clear()
+        test_object["test_string_prop"] = "Hello there!"
+        ui_data_test_prop_string = test_object.id_properties_ui("test_string_prop")
+        ui_data_test_prop_string.update(default="Goodbye where?")
+        rna_data = ui_data_test_prop_string.as_dict()
+        self.assertEqual(rna_data["default"], "Goodbye where?")
+
+        # Test RNA data for array property.
+        test_object.id_properties_clear()
+        test_object["test_array_prop"] = [1, 2, 3]
+        ui_data_test_prop_array = test_object.id_properties_ui("test_array_prop")
+        ui_data_test_prop_array.update(default=[1, 2])
+        rna_data = ui_data_test_prop_array.as_dict()
+        self.assertEqual(rna_data["default"], [1, 2])
+
+
 
 if __name__ == '__main__':
     import sys