The SBFOSFHM uses [[https://github.com/osmarks/misc/blob/master/computercraft/stitch_dynmap.py|composited dynmap images]] and hologram projectors to render a map in a uselessly low-resolution, somewhat cool-looking way, including overlays for player locations.
Due to technical limitations it was not able to render in 3D, thus making it a strictly worse version of a 2D display.