Node3D gizmo improvements

* Clean-up of node_3d_editor_plugin.{h,cpp}: removed unused code, fixed some bugs.
* Moved node_3d_editor_gizmos.{h,cpp} to editor/plugins.
* Added support for multiple gizmos per node. This means custom gizmos will no longer override the built-in ones and that multiple gizmos can be used in more complex nodes.
* Added support for handle IDs. When adding handles to a gizmo, an ID can be specified for each one, making it easier to work with gizmos that have a variable number of handles.
* Added support for subgizmos, selectable elements that can be transformed without needing a node of their own. By overriding _subgizmo_intersect_frustum() and/or _subgizmo_intersect_ray() gizmos can define which subgizmos should be selected on a region or click selection. Subgizmo transformations are applied using get/set/commit virtual methods, similar to how handles work.

1 files changed, 1 insertions, 0 deletions

diff --git a/scene/scene_string_names.cpp b/scene/scene_string_names.cpp
index d53d155cce..b8173c9623 100644
--- a/scene/scene_string_names.cpp
+++ b/scene/scene_string_names.cpp
@@ -136,6 +136,7 @@ SceneStringNames::SceneStringNames() {
 
 	_spatial_editor_group = StaticCString::create("_spatial_editor_group");
 	_request_gizmo = StaticCString::create("_request_gizmo");
+	_clear_subgizmo_selection = StaticCString::create("_clear_subgizmo_selection");
 
 	offset = StaticCString::create("offset");
 	unit_offset = StaticCString::create("unit_offset");