Indexed by the facing (0-3) with bit 1 flipped when the town is turned round (TURN_KNIGHT, from offset 139). Bits 6-7 go into the flags -- bit 6 mirrors the picture; bit 7, upside down, is never set -- and bit 3 into the graphic, the view from the front, his face showing (24-29 rather than 16-21, seen from behind). Facing +U or -V he comes towards the viewer, since further back is smaller U and larger V (DEPTH_TABLE); drawn by the game's own code, those two show his face.