Variable star mapping

Can variable stars be used to map out the structure of the Galactic disk? Why or why not? If the variable stars are recognized as RR Lyrae or a Cepheid, their luminosity can be concluded. Since we conclude the luminosity we can calculate the estimated distance using inverse square law. This is done by comparing the star’s luminosity with its apparent brightness. The distance between the stars, their luminosity etc. helps us to map the structure of the Galactic disk