When afire or other accidents occurs in a large shopping mall or at a transportation hub, elevator or escalator facilities cannot be used. People in panic may easily face situations where stairs cannot be found, or a detour was necessary.
In the conventional navigation techniques, origin and destination are generally selected manually, before the routes are planned. The routes include all possible means that can reach the destination. When an accident occurs, due to the panic, users will likely click wrong points or select an exit not through the shortest route, thus wasting time during the emergency evacuation.