private static extern void session_SetPlaneAnchorCallbacks(IntPtr nativeSession, internal_ARAnchorAdded anchorAddedCallback,
                                                            internal_ARAnchorUpdated anchorUpdatedCallback,
                                                            internal_ARAnchorRemoved anchorRemovedCallback);
 private static extern IntPtr unity_CreateNativeARSession(internal_ARFrameUpdate frameUpdate, internal_ARAnchorAdded anchorAdded, internal_ARAnchorUpdated anchorUpdated, internal_ARAnchorRemoved anchorRemoved, ARSessionFailed sessionFailed);