seafloor

The abyssal plain of DEADLIGHT. The mesh under it carries only the large undulations; the ripple marks, the silt grain, the ochre sorting and the pale crest dusting are all computed per pixel from the fragment's own world XZ, so a camera 30 cm off the floor reads ripples a hand's width apart and the same surface still runs out to the limit of the light.

Ripple direction turns slowly across the plain, and the ripple field fades in and out in patches, so nothing about the floor reads as a repeating tile. The highest frequencies fade out with distance from the camera, which is what keeps a plain that reaches the edge of the light from aliasing into noise.

Exposes surface(), so the engine lights it — the submersible's two floods and its forward spot are the only lights that ever reach it.