Illustrations of mask occupation for an example galaxy visualized as PV-diagrams, with positional offset from the galaxy center on the horizontal axis and line-of-sight velocity on the vertical axis. The cross-section along the major axis is shown in the left plot and along the minor axis in the right plot. The example galaxy has a major axis S = 10 and inclination i = 45°. The color denotes the occupation for three different levels of padding, including zero padding.