# IRON ABYSS

A retro first-person shooter written in PHP with [JumPHP](https://git.jumphp.net/jumphp/jumPhp): it runs on the desktop
and in the browser (PHP compiled to WebAssembly).

- **Engine**: a PHP port of the software renderer and game logic of the 1993 engine whose C source id Software released
  under the GNU GPL (https://github.com/id-Software/DOOM): BSP walk with solid-seg clipping, wall columns, visplanes,
  colormap lighting, sprites clipped by silhouettes, 35 Hz tics, thing state machines, monster AI (look / chase /
  new chase direction), hitscan with vertical autoaim, sight checks, doors, lifts, lights, sound propagation.
  The BSP tree is built at load time by `src/Engine/Map/NodeBuilder.php`.
- **Content**: original. Monsters (husk, gnasher, spitter, warden), weapons (wrench, sidearm, scattergun, riveter,
  ion launcher), textures, sky and sounds are generated by code (`tools/make-art.php`, `tools/art/`); the three
  levels are drawn in text (`assets/maps/*.json`). No file of the original game is used.

```bash
bin/jumphp run doom-jumphp       # play on the desktop
bin/jumphp test doom-jumphp      # lint, phpstan, the game tests, the smoke test
bin/jumphp build doom-jumphp     # browser version -> dist/web
bin/jumphp php games/doom-jumphp tools/make-art.php preview   # rebuild assets/data/art.pak and assets/sfx
```

Controls: arrows / W S move and turn, A D (or Q D) strafe, Shift run, Ctrl / F / click fire, Space / E use
(doors, switches, lifts), 1-5 weapons, Tab map, Escape menu.

License: GNU GPL v2 or later (see LICENSE), as a derived work of the GPL engine source.