Evolution of Lyα flux with angular quadrature methods. The black and cyan lines are the flux computed by MCFOST and RH, respectively, from Fig. 8a. The dotted red line and the pink triangles are the flux computed using option (i) and (ii) of Sect. 3.8, respectively. The bottom panel shows the discrepancy between RH and MCFOST, from Fig. 8a (dark grey line), option (i) (light grey dotted line), and option (ii) (grey triangles).