Fix custom elements nested under @Property (nerfstudio-project#3066)

* patch custom elements bug

* Skip `cached_property`

* fomrat

* comment, type hint

---------

Co-authored-by: Brent Yi <yibrenth@gmail.com>

nerfstudio/viewer/utils.py

@@ -15,7 +15,8 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import Any, List, Literal, Optional, Tuple, Union
+from functools import cached_property
+from typing import Any, List, Literal, Optional, Tuple, Type, Union
 
 import numpy as np
 import torch
@@ -109,7 +110,7 @@ def update_render_aabb(
 
 def parse_object(
     obj: Any,
-    type_check,
+    type_check: Type[Any],
     tree_stub: str,
 ) -> List[Tuple[str, Any]]:
     """
@@ -138,7 +139,8 @@ def add(ret: List[Tuple[str, Any]], ts: str, v: Any):
         return []
     ret = []
     # get a list of the properties of the object, sorted by whether things are instances of type_check
-    obj_props = [(k, v) for k, v in vars(obj).items()]
+    # we skip cached properties, which can be expensive to call `getattr()` on!
+    obj_props = [(k, getattr(obj, k)) for k in dir(obj) if not isinstance(getattr(type(obj), k, None), cached_property)]
     for k, v in obj_props:
         if k[0] == "_":
             continue