add extension to set layers for whole hierarchy

Assets/Scripts/OpenTS2/GameObjectExtensions.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace OpenTS2
+{
+    public static class GameObjectExtensions
+    {
+        public static void SetLayerHierarchy(this GameObject go, int layer)
+        {
+            var transforms = go.GetComponentsInChildren<Transform>();
+            foreach(var transform in transforms)
+            {
+                transform.gameObject.layer = layer;
+            }
+        }
+    }
+}