- Lenses no longer produce light from sun at all;
artificial light is always needed.
- Grass and trees survive, don't do dual-time check.
- Breeze sounds work in twilight.
- Sponge drying only requires twilight, now also can
happen under artificial light.
- Peat to grass happens under twilight.
- No day/night cycle, no sun/moon.
- Get rid of clouds too.
- Skybox is now 100% texture-packable.
- Natural light diminishes with depth.
Night-time no longer disrupts gameplay topside, but
skylights are no longer useful to an infinite depth and
artificial light is necessary for all deep mining.
