Cleanup: Better name for new Outliner tree element type

The name `type` was confusing, since we usually use that in other ways.

Also updated the relating comments.

2 files changed, 18 insertions, 17 deletions

diff --git a/source/blender/editors/space_outliner/outliner_intern.hh b/source/blender/editors/space_outliner/outliner_intern.hh
index ccadc829f50..bd288241a63 100644
--- a/source/blender/editors/space_outliner/outliner_intern.hh
+++ b/source/blender/editors/space_outliner/outliner_intern.hh
@@ -95,11 +95,12 @@ typedef struct TreeElement {
   struct TreeElement *next, *prev, *parent;
 
   /**
-   * Handle to the new C++ object (a derived type of base #AbstractTreeElement) that should replace
-   * #TreeElement. Step by step, data should be moved to it and operations based on the type should
-   * become virtual methods of the class hierarchy.
+   * The new inheritance based representation of the element (a derived type of base
+   * #AbstractTreeElement) that should eventually replace #TreeElement. Step by step, data should
+   * be moved to it and operations based on the type should become virtual methods of the class
+   * hierarchy.
    */
-  std::unique_ptr<outliner::AbstractTreeElement> type;
+  std::unique_ptr<outliner::AbstractTreeElement> abstract_element;
 
   ListBase subtree;
   int xs, ys;                /* Do selection. */
@@ -702,7 +703,7 @@ template<typename TreeElementT> TreeElementT *tree_element_cast(const TreeElemen
 {
   static_assert(std::is_base_of_v<AbstractTreeElement, TreeElementT>,
                 "Requested tree-element type must be an AbstractTreeElement");
-  return dynamic_cast<TreeElementT *>(te->type.get());
+  return dynamic_cast<TreeElementT *>(te->abstract_element.get());
 }
 
 }  // namespace blender::ed::outliner
diff --git a/source/blender/editors/space_outliner/outliner_tree.cc b/source/blender/editors/space_outliner/outliner_tree.cc
index eb885eba20d..d8fe17a570f 100644
--- a/source/blender/editors/space_outliner/outliner_tree.cc
+++ b/source/blender/editors/space_outliner/outliner_tree.cc
@@ -217,7 +217,7 @@ void outliner_free_tree_element(TreeElement *element, ListBase *parent_subtree)
   if (element->flag & TE_FREE_NAME) {
     MEM_freeN((void *)element->name);
   }
-  element->type = nullptr;
+  element->abstract_element = nullptr;
   MEM_delete(element);
 }
 
@@ -860,10 +860,10 @@ TreeElement *outliner_add_element(SpaceOutliner *space_outliner,
   te->parent = parent;
   te->index = index; /* For data arrays. */
 
-  /* New C++ based type handle. Only some support this, eventually this should replace
-   * `TreeElement` entirely. */
-  te->type = AbstractTreeElement::createFromType(type, *te, idv);
-  if (te->type) {
+  /* New inheritance based element representation. Not all element types support this yet,
+   * eventually it should replace #TreeElement entirely. */
+  te->abstract_element = AbstractTreeElement::createFromType(type, *te, idv);
+  if (te->abstract_element) {
     /* Element types ported to the new design are expected to have their name set at this point! */
     BLI_assert(te->name != nullptr);
   }
@@ -887,12 +887,12 @@ TreeElement *outliner_add_element(SpaceOutliner *space_outliner,
     /* pass */
   }
   else if (type == TSE_SOME_ID) {
-    if (!te->type) {
+    if (!te->abstract_element) {
       BLI_assert_msg(0, "Expected this ID type to be ported to new Outliner tree-element design");
     }
   }
   else if (ELEM(type, TSE_LIBRARY_OVERRIDE_BASE, TSE_LIBRARY_OVERRIDE)) {
-    if (!te->type) {
+    if (!te->abstract_element) {
       BLI_assert_msg(0,
                      "Expected override types to be ported to new Outliner tree-element design");
     }
@@ -903,20 +903,20 @@ TreeElement *outliner_add_element(SpaceOutliner *space_outliner,
 
     /* The new type design sets the name already, don't override that here. We need to figure out
      * how to deal with the idcode for non-TSE_SOME_ID types still. Some rely on it... */
-    if (!te->type) {
+    if (!te->abstract_element) {
       te->name = id->name + 2; /* Default, can be overridden by Library or non-ID data. */
     }
     te->idcode = GS(id->name);
   }
 
-  if (te->type && te->type->isExpandValid()) {
-    tree_element_expand(*te->type, *space_outliner);
+  if (te->abstract_element && te->abstract_element->isExpandValid()) {
+    tree_element_expand(*te->abstract_element, *space_outliner);
   }
   else if (type == TSE_SOME_ID) {
     /* ID types not (fully) ported to new design yet. */
-    if (te->type->expandPoll(*space_outliner)) {
+    if (te->abstract_element->expandPoll(*space_outliner)) {
       outliner_add_id_contents(space_outliner, te, tselem, id);
-      te->type->postExpand(*space_outliner);
+      te->abstract_element->postExpand(*space_outliner);
     }
   }
   else if (ELEM(type,