Lyα spectra using a setup of outflowing clumps with linear velocity profile for N_HI,cl = 10¹⁷ cm^-2 and four different maximal velocities v_max. The dashed lines in corresponding colors show the spectra emergent from a slab with the same column density and velocity structure. Each subpanel displays a case with different covering factor corresponding to increasing agreement with the homogeneous setup.