ref: b6257bd3fead9cfaa9a408daa7425337c0fc974c
dir: /examples/filter.orca/
......................................... .#.FILTER.#.............................. ......................................... ......................................... ......................................... ......................................... .......................3D................ ..............8D.H....................... ................xE......u................ .......................E.......E.......E. ......................................... ......................................... ......................................... ......................................... ......................................... ......................................... .........................................