LibOverride: Rename 'delete hierarchy' to 'clear hierarchy', add 'clear single' operations.

'Delete' was a confusing name, even though it would delete the overrides
it would replace them by linked data.

Adding the 'single' version of that operation made it even more
confusing, since often it has to keep the override ID for sakes of
hierarchy, and just reset it and turn it back into a non-editable system
override.

Ref: {T95707}.

2 files changed, 132 insertions, 35 deletions

diff --git a/source/blender/editors/space_outliner/outliner_edit.cc b/source/blender/editors/space_outliner/outliner_edit.cc
index ae67e7108bf..d6c5901b546 100644
--- a/source/blender/editors/space_outliner/outliner_edit.cc
+++ b/source/blender/editors/space_outliner/outliner_edit.cc
@@ -30,6 +30,7 @@
 #include "BKE_context.h"
 #include "BKE_idtype.h"
 #include "BKE_lib_id.h"
+#include "BKE_lib_override.h"
 #include "BKE_lib_query.h"
 #include "BKE_lib_remap.h"
 #include "BKE_main.h"
diff --git a/source/blender/editors/space_outliner/outliner_tools.cc b/source/blender/editors/space_outliner/outliner_tools.cc
index 6593fb9b6af..22e42c762ca 100644
--- a/source/blender/editors/space_outliner/outliner_tools.cc
+++ b/source/blender/editors/space_outliner/outliner_tools.cc
@@ -47,6 +47,7 @@
 #include "BKE_lib_id.h"
 #include "BKE_lib_override.h"
 #include "BKE_lib_query.h"
+#include "BKE_lib_remap.h"
 #include "BKE_main.h"
 #include "BKE_object.h"
 #include "BKE_report.h"
@@ -1008,6 +1009,23 @@ static void id_override_library_create_hierarchy_post_process(bContext *C,
   FOREACH_MAIN_ID_END;
 }
 
+static void id_override_library_toggle_flag_fn(bContext *UNUSED(C),
+                                               ReportList *UNUSED(reports),
+                                               Scene *UNUSED(scene),
+                                               TreeElement *UNUSED(te),
+                                               TreeStoreElem *UNUSED(tsep),
+                                               TreeStoreElem *tselem,
+                                               void *user_data)
+{
+  BLI_assert(TSE_IS_REAL_ID(tselem));
+  ID *id = tselem->id;
+
+  if (ID_IS_OVERRIDE_LIBRARY_REAL(id)) {
+    const uint flag = POINTER_AS_UINT(user_data);
+    id->override_library->flag ^= flag;
+  }
+}
+
 static void id_override_library_reset_fn(bContext *C,
                                          ReportList *UNUSED(reports),
                                          Scene *UNUSED(scene),
@@ -1025,10 +1043,10 @@ static void id_override_library_reset_fn(bContext *C,
     Main *bmain = CTX_data_main(C);
 
     if (do_hierarchy) {
-      BKE_lib_override_library_id_hierarchy_reset(bmain, id_root);
+      BKE_lib_override_library_id_hierarchy_reset(bmain, id_root, false);
     }
     else {
-      BKE_lib_override_library_id_reset(bmain, id_root);
+      BKE_lib_override_library_id_reset(bmain, id_root, false);
     }
 
     WM_event_add_notifier(C, NC_WM | ND_DATACHANGED, nullptr);
@@ -1080,40 +1098,76 @@ static void id_override_library_resync_fn(bContext *C,
   }
 }
 
-static void id_override_library_delete_fn(bContext *C,
-                                          ReportList *UNUSED(reports),
-                                          Scene *UNUSED(scene),
-                                          TreeElement *te,
-                                          TreeStoreElem *UNUSED(tsep),
-                                          TreeStoreElem *tselem,
-                                          void *UNUSED(user_data))
+static void id_override_library_clear_hierarchy_fn(bContext *C,
+                                                   ReportList *UNUSED(reports),
+                                                   Scene *UNUSED(scene),
+                                                   TreeElement *te,
+                                                   TreeStoreElem *UNUSED(tsep),
+                                                   TreeStoreElem *tselem,
+                                                   void *UNUSED(user_data))
 {
   BLI_assert(TSE_IS_REAL_ID(tselem));
   ID *id_root = tselem->id;
 
-  if (ID_IS_OVERRIDE_LIBRARY_REAL(id_root)) {
-    Main *bmain = CTX_data_main(C);
+  if (!ID_IS_OVERRIDE_LIBRARY_REAL(id_root)) {
+    CLOG_WARN(&LOG, "Could not delete library override of data block '%s'", id_root->name);
+    return;
+  }
 
-    id_root->tag |= LIB_TAG_DOIT;
+  Main *bmain = CTX_data_main(C);
 
-    /* Tag all linked parents in tree hierarchy to be also overridden. */
-    while ((te = te->parent) != nullptr) {
-      if (!TSE_IS_REAL_ID(te->store_elem)) {
-        continue;
-      }
-      if (!ID_IS_OVERRIDE_LIBRARY_REAL(te->store_elem->id)) {
-        break;
-      }
-      te->store_elem->id->tag |= LIB_TAG_DOIT;
+  id_root->tag |= LIB_TAG_DOIT;
+
+  /* Tag all override parents in tree hierarchy to be also processed. */
+  while ((te = te->parent) != nullptr) {
+    if (!TSE_IS_REAL_ID(te->store_elem)) {
+      continue;
+    }
+    if (!ID_IS_OVERRIDE_LIBRARY_REAL(te->store_elem->id)) {
+      break;
     }
+    te->store_elem->id->tag |= LIB_TAG_DOIT;
+  }
 
-    BKE_lib_override_library_delete(bmain, id_root);
+  BKE_lib_override_library_delete(bmain, id_root);
 
-    WM_event_add_notifier(C, NC_WINDOW, nullptr);
+  WM_event_add_notifier(C, NC_WINDOW, nullptr);
+}
+
+static void id_override_library_clear_single_fn(bContext *C,
+                                                ReportList *reports,
+                                                Scene *UNUSED(scene),
+                                                TreeElement *UNUSED(te),
+                                                TreeStoreElem *UNUSED(tsep),
+                                                TreeStoreElem *tselem,
+                                                void *UNUSED(user_data))
+{
+  BLI_assert(TSE_IS_REAL_ID(tselem));
+  Main *bmain = CTX_data_main(C);
+  ID *id = tselem->id;
+
+  if (!ID_IS_OVERRIDE_LIBRARY_REAL(id)) {
+    BKE_reportf(reports,
+                RPT_WARNING,
+                "Cannot clear embedded library override id '%s', only overrides of real "
+                "data-blocks can be directly deleted",
+                id->name);
+    return;
+  }
+
+  /* If given ID is not using any other override (it's a 'leaf' in the override hierarchy),
+   * delete it and remap its usages to its linked reference. Otherwise, keep it as a reset system
+   * override. */
+  if (BKE_lib_override_library_is_hierarchy_leaf(bmain, id)) {
+    BKE_libblock_remap(bmain, id, id->override_library->reference, ID_REMAP_SKIP_INDIRECT_USAGE);
+    BKE_id_delete(bmain, id);
   }
   else {
-    CLOG_WARN(&LOG, "Could not delete library override of data block '%s'", id_root->name);
+    BKE_lib_override_library_id_reset(bmain, id, true);
   }
+
+  WM_event_add_notifier(C, NC_WINDOW, nullptr);
+  return;
 }
 
 static void id_fake_user_set_fn(bContext *UNUSED(C),
@@ -1911,11 +1965,13 @@ enum eOutlinerIdOpTypes {
   OUTLINER_IDOP_LOCAL,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_CREATE,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_CREATE_HIERARCHY,
+  OUTLINER_IDOP_OVERRIDE_LIBRARY_MAKE_EDITABLE,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET_HIERARCHY,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_RESYNC_HIERARCHY,
   OUTLINER_IDOP_OVERRIDE_LIBRARY_RESYNC_HIERARCHY_ENFORCE,
-  OUTLINER_IDOP_OVERRIDE_LIBRARY_DELETE_HIERARCHY,
+  OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_HIERARCHY,
+  OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_SINGLE,
   OUTLINER_IDOP_SINGLE,
   OUTLINER_IDOP_DELETE,
   OUTLINER_IDOP_REMAP,
@@ -1954,6 +2010,11 @@ static const EnumPropertyItem prop_id_op_types[] = {
      "Make Library Override Hierarchy",
      "Make a local override of this linked data-block, and its hierarchy of dependencies - only "
      "applies to active Outliner item"},
+    {OUTLINER_IDOP_OVERRIDE_LIBRARY_MAKE_EDITABLE,
+     "OVERRIDE_LIBRARY_MAKE_EDITABLE",
+     0,
+     "Make Library Override Editable",
+     "Make the library override data-block editable"},
     {OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET,
      "OVERRIDE_LIBRARY_RESET",
      0,
@@ -1977,12 +2038,18 @@ static const EnumPropertyItem prop_id_op_types[] = {
      "Rebuild this local override from its linked reference, as well as its hierarchy of "
      "dependencies, enforcing that hierarchy to match the linked data (i.e. ignoring exiting "
      "overrides on data-blocks pointer properties)"},
-    {OUTLINER_IDOP_OVERRIDE_LIBRARY_DELETE_HIERARCHY,
-     "OVERRIDE_LIBRARY_DELETE_HIERARCHY",
+    {OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_HIERARCHY,
+     "OVERRIDE_LIBRARY_CLEAR_HIERARCHY",
      0,
-     "Delete Library Override Hierarchy",
+     "Clear Library Override Hierarchy",
      "Delete this local override (including its hierarchy of override dependencies) and relink "
      "its usages to the linked data-blocks"},
+    {OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_SINGLE,
+     "OVERRIDE_LIBRARY_CLEAR_SINGLE",
+     0,
+     "Clear Single Library Override",
+     "Delete this local override if possible, else reset it and mark it as non editable, and "
+     "relink its usages to the linked data-blocks"},
     {0, "", 0, nullptr, nullptr},
     {OUTLINER_IDOP_COPY, "COPY", ICON_COPYDOWN, "Copy", ""},
     {OUTLINER_IDOP_PASTE, "PASTE", ICON_PASTEDOWN, "Paste", ""},
@@ -2026,11 +2093,19 @@ static bool outliner_id_operation_item_poll(bContext *C,
         return true;
       }
       return false;
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_MAKE_EDITABLE:
+      if (ID_IS_OVERRIDE_LIBRARY_REAL(tselem->id) && !ID_IS_LINKED(tselem->id)) {
+        if (tselem->id->override_library->flag & IDOVERRIDE_LIBRARY_FLAG_SYSTEM_DEFINED) {
+          return true;
+        }
+      }
+      return false;
     case OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET:
     case OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET_HIERARCHY:
     case OUTLINER_IDOP_OVERRIDE_LIBRARY_RESYNC_HIERARCHY:
     case OUTLINER_IDOP_OVERRIDE_LIBRARY_RESYNC_HIERARCHY_ENFORCE:
-    case OUTLINER_IDOP_OVERRIDE_LIBRARY_DELETE_HIERARCHY:
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_HIERARCHY:
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_SINGLE:
       if (ID_IS_OVERRIDE_LIBRARY_REAL(tselem->id) && !ID_IS_LINKED(tselem->id)) {
         return true;
       }
@@ -2211,6 +2286,18 @@ static int outliner_id_operation_exec(bContext *C, wmOperator *op)
       ED_undo_push(C, "Overridden Data Hierarchy");
       break;
     }
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_MAKE_EDITABLE: {
+      outliner_do_libdata_operation(C,
+                                    op->reports,
+                                    scene,
+                                    space_outliner,
+                                    &space_outliner->tree,
+                                    id_override_library_toggle_flag_fn,
+                                    POINTER_FROM_UINT(IDOVERRIDE_LIBRARY_FLAG_SYSTEM_DEFINED));
+
+      ED_undo_push(C, "Make Overridden Data Editable");
+      break;
+    }
     case OUTLINER_IDOP_OVERRIDE_LIBRARY_RESET: {
       OutlinerLibOverrideData override_data{};
       outliner_do_libdata_operation(C,
@@ -2263,17 +2350,26 @@ static int outliner_id_operation_exec(bContext *C, wmOperator *op)
       ED_undo_push(C, "Resync Overridden Data Hierarchy");
       break;
     }
-    case OUTLINER_IDOP_OVERRIDE_LIBRARY_DELETE_HIERARCHY: {
-      OutlinerLibOverrideData override_data{};
-      override_data.do_hierarchy = true;
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_HIERARCHY: {
       outliner_do_libdata_operation(C,
                                     op->reports,
                                     scene,
                                     space_outliner,
                                     &space_outliner->tree,
-                                    id_override_library_delete_fn,
-                                    &override_data);
-      ED_undo_push(C, "Delete Overridden Data Hierarchy");
+                                    id_override_library_clear_hierarchy_fn,
+                                    nullptr);
+      ED_undo_push(C, "Clear Overridden Data Hierarchy");
+      break;
+    }
+    case OUTLINER_IDOP_OVERRIDE_LIBRARY_CLEAR_SINGLE: {
+      outliner_do_libdata_operation(C,
+                                    op->reports,
+                                    scene,
+                                    space_outliner,
+                                    &space_outliner->tree,
+                                    id_override_library_clear_single_fn,
+                                    nullptr);
+      ED_undo_push(C, "Clear Overridden Data Hierarchy");
       break;
     }
     case OUTLINER_IDOP_SINGLE: {