rename nano model

hw3d/App.h

@@ -25,5 +25,5 @@ private:
 	float speed_factor = 1.0f;
 	Camera cam;
 	PointLight light;
-	Model nano{ wnd.Gfx(),"Models\\nano.gltf" };
+	Model nano{ wnd.Gfx(),"Models\\nano_hierarchy.gltf" };
 };
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