How does vision work in nethack

nethack

As is immediately obvious the first time you play nethack, you can't see much until you move around a bit. Here are some basic things I've figured out:

  • You can see things within one block of yourself, diagonals included.
  • You can see anything within line of sight in most rooms.
  • You remember the map and things on it (like corpses) but upon returning to them, they disappear (is this just the map updating?).
  • Sometimes getting within one block isn't enough, and searching reveals more.
  • You can be blinded and see nothing.

It's still a bit confusing though. Sometimes I can see monsters at a distance, other times I can't see them until they're one block away. What are the rules for vision? Are there certain things that can increase my vision? Any other general see-them-before-they-see-me tips?

Best Answer

Your vision is based on the amount of light in the area. Most rooms are fully lit, so you can see the entirety of it. The same goes for most levels of the Gnomish Mines for example.

Corridors are not lit, which means you can only see one block in any direction. One exception is infravision, which is an intrinsic for dwarves, elves, gnomes, and orcs, allowing you to see infravisible (warm-blooded) monsters from afar, even in dark places.

As for the map, you recall the way things were the last time you saw them. If something happens to them but you're not around to see it, you obviously don't know of it. You will only see the change once you get within sight again.