Edge-on (top) and face-on (bottom) views of G1. In both panels, the gray scale indicates the density of neutral hydrogen (maximum value in a slice of thickness 8 high-resolution cells). The arrows indicate the velocity field of the gas at the location where photons last scatter before they are observed (the double sided arrow in the bottom left corner of each panel gives the scale), and their color scales with the log₁₀ of the number of photons seen from each cell (red: lots of photons; blue: small number of photons).