Qualitative picture of the proposed high and low optical states. Shown are the WD, the accretion disc, and blobs or clouds above the disc. Upper panel – high optical state; the low luminous WD is compact, and its X-ray emission is effectively reprocessed into optical light due to multiple scattering between clouds. Lower panel – low optical state; the luminous WD with an expanded photosphere evaporates most of clouds decreasing the reprocessing efficiency and reducing the optical flux.