Partition of unity for the rotation-based reconstruction. The weights smoothly decaying toward the border are presented in the top left panel and are copied to each HEALPix face in the top right panel. In the bottom left panel, resampling was first performed using a rotation and bilinear interpolation, and the image shows the weights that would be applied in the original reference coordinates. The resulting covering of the sphere using five rotations is illustrated in the bottom right panel.