Should the same seed always give the exact same map?

[mrvn]

I'm wondering if using the same seed and map gen settings should give the same map every time or if the map could differ depending on your game play.

First, lets explicitly exclude replays. A replay must produce the same map. I'm talking about starting the same map and then playing differently. Also I mean maps generated / modified by mods. I know the vanilla map generator uses noise function that always give the same map (excluding aliens?).

Don't aliens already behave different even in vanilla. If you explore a region early the game creates weak aliens there. On the other hand if you play a few hours the aliens will evolve and if you then explore the same region you get stronger aliens, right?

More importantly though should the resources in a given region be always the same? For example you start a new map and explore to the right in search of some uranium. After a while you give up, go back to the start and explore to the left and quickly find some uranium. Now when you restart the map with the same seed you already know where uranium is and go left from the start.

Should the uranium be in the same place? Or would it be ok if that changes because by not exploring all the way to the right less resources are placed and a mod only places uranium after N other resouces haven been discovered? Similar I'm considering placing resources proportional to their use. If you mine lots and lots of coal then coal will become more frequent. Don't use any uranium then the chance of finding more goes down. So somebody using steam power gets a different map from someone using solar and different from someone going for nuclear power. Any of those ideas would lead to maps where the same seed and settings would generate different maps depending on the game played.

What is your opinion about such variance in maps?

[Koub]

A seed is the "starting point" allowing to generate a finished product after a definite set of steps. I'd be shocked if the same seed didn't give the same exact map, for a given set of map settings.
I'd even say it's one of the purposes of a seed.

[Twitchi]

Are you actually asking if gameplay decisions lead to maps developing differently?
You talk about the natives reacting differently depending on your exploration.. yes I think this is fine and as It should be.. they are a dynamic system responding to your actions.. but I feel the "starting villages" should spawn in the same location for the same seed, same with ore location

as Koub says "I'd even say it's one of the purposes of a seed." and I would agree.. if your looking for THAT much variation between maps you should be using new seeds
(also whilst it would be lots of extra work.. I would welcome separate terrain, biter and resource seeds)

[mrvn]

Yes. I'm asking if, for a mod, it would be acceptable for gameplay decisions to lead to maps developing differently.

In the simple examples I gave the resource type or quantity would change. In a more complex case of a dynamically generated maze the actual maze could change depending on the order in which chunks are explored.

[xfir01]

Yes. I'm asking if, for a mod, it would be acceptable for gameplay decisions to lead to maps developing differently.

In the simple examples I gave the resource type or quantity would change. In a more complex case of a dynamically generated maze the actual maze could change depending on the order in which chunks are explored.

I think the exact same map is what people would expect. Same settings, same seed, same map.

If you're making a mod that changes map generation you can throw that out the window and have it work however you want. They accept it by downloading the mod, or if it's not acceptable they don't. I would make it clear that the map generation is based on the previous game state and not the seed though.