Luminosity in 3 γ-ray bands as a function of SFR and cosmic-ray power, for a star-forming disk galaxy with (R_max, z_max) = (10 kpc, 2 kpc), 4 profiles of molecular gas (given in abscissa), and 7 molecular gas densities for each profile (n_H2 = 5, 10, 20, 50, 100, 200, 500 H₂ cm^-3). The cosmic-ray input power generated by the galaxy is assumed to scale with the total SFR, using the Milky Way as normalisation.