add RuntimeGltfInstance.VisibleRenderers

Assets/UniGLTF/Runtime/UniGLTF/RuntimeGltfInstance.cs

@@ -64,6 +64,14 @@ namespace UniGLTF
         /// </summary>
         public IReadOnlyList<SkinnedMeshRenderer> SkinnedMeshRenderers => _skinnedMeshRenderers;
 
+        /// <summary>
+        /// ShowMeshes の対象になる Renderer。
+        /// Destroy対象とは無関係なので、自由に操作して OK。
+        /// </summary>
+        /// <typeparam name="Renderer"></typeparam>
+        /// <returns></returns>
+        public readonly List<Renderer> VisibleRenderers = new List<Renderer>();
+
         private readonly List<Transform> _nodes = new List<Transform>();
         private readonly List<(SubAssetKey, UnityEngine.Object)> _resources = new List<(SubAssetKey, UnityEngine.Object)>();
         private readonly List<Material> _materials = new List<Material>();
@@ -120,6 +128,8 @@ namespace UniGLTF
         {
             _renderers.Add(renderer);
 
+            VisibleRenderers.Add(renderer);
+
             switch (renderer)
             {
                 case MeshRenderer meshRenderer:
@@ -133,7 +143,7 @@ namespace UniGLTF
 
         public void ShowMeshes()
         {
-            foreach (var r in Renderers)
+            foreach (var r in VisibleRenderers)
             {
                 r.enabled = true;
             }