Intensity (top row), linear polarization degree (middle row), and polarization angle (bottom row) of the observed radiation in test cases 1 through 3 (left to right columns). The top section in each panel shows the analytical solution (black) and the model results (dashed orange). The bottom section in each panel shows the absolute differences (blue) and relative differences (shaded area) of the analytic solution and the model. The green lines are calculated using twice the resolution of the θ scattering angle.