Implement Animation Libraries

* Instead of containing single animations, AnimationPlayer now contains libraries.
* Libraries, in turn, contain the animations.

This paves the way for implementing the possibility of importing scenes as animation libraries, finally allowing to import animations separate from the 3D models.

Missing (will be done on separate PRs):

* Make it possible to import scenes (dae/fbx/gltf) as animation libraries.
* Make it possible for AnimationTree to import animation libraries on its own, so it does not rely on AnimationPlayer for everything.

1 files changed, 4 insertions, 1 deletions

diff --git a/scene/gui/tree.h b/scene/gui/tree.h
index 74ad4f94b8..b704495444 100644
--- a/scene/gui/tree.h
+++ b/scene/gui/tree.h
@@ -379,6 +379,9 @@ private:
 	TreeItem *selected_item = nullptr;
 	TreeItem *edited_item = nullptr;
 
+	TreeItem *popup_pressing_edited_item = nullptr; // Candidate.
+	int popup_pressing_edited_item_column = -1;
+
 	TreeItem *drop_mode_over = nullptr;
 	int drop_mode_section = 0;
 
@@ -673,7 +676,7 @@ public:
 	Rect2 get_custom_popup_rect() const;
 
 	int get_item_offset(TreeItem *p_item) const;
-	Rect2 get_item_rect(TreeItem *p_item, int p_column = -1) const;
+	Rect2 get_item_rect(TreeItem *p_item, int p_column = -1, int p_button = -1) const;
 	bool edit_selected();
 	bool is_editing();