[0.11.21]-[0.12]Water only in starting area causes no trees

[SirRichie]

Summary:
When I use the setting "Only in starting area" for water, the generated map has no trees, except for dead trees (the ones that have fallen over).

Details:
I first encountered this when playing with a friend in multiplayer. At first we thought that we had been "lucky" not to have trees in our way.
Further map generation for new games gave consistent results: When I enable "Only in starting area", there are no trees, if I disable it, there are trees.

I thought that it might be some kind of bug, or a side effect of playing around with programming a mod (although I didn't do anything with trees). But now that 0.12 is out, I did a completely fresh, new install (uninstalled the old game, wiped %appdata%\Factorio and the install folder, then installed the new game). Same behavior.

Now this might be just my machine/setup, but I am curious if other people can reproduce the issue or came across it. There is another entry in the "Not a bug" forum (https://forums.factorio.com/forum/vie ... 23&t=12524) which is concerned with ugly maps. I am not concerned with the visual beauty, but the screenshots given in that post very closely resemble what I am seeing: no trees when using "Only in starting area".

As a side effect: I do not really get grasslands when using "Only in starting area".

Let me know if I can help with more info or bash me if I reported a feature or a very well known issue (even though I searched!)

[Racusthor]

I noticed this too.but i always thought this was on purpose, since trees and grass need water.
Kind of like a dessert.

[SirRichie]

I know that it has been different, but I cannot find a related entry in the changelog, so I figured it is unintentional

[FishSandwich]

It makes sense, because trees and grass cannot survive without water.

Anyway, this post is probably what you were looking for: https://forums.factorio.com/forum/vie ... 47&p=66254

[SirRichie]

So I guess it is intentional.

And whether it makes sense or not (from nature's perspective) wasn't the question. If you are taking that angle, then there should be trees around the water in the starting area, but nowhere else. And the number of trees should also depend on how much water you have on the map. I doubt this is the case, this seems to be a 1/0 thing.

[FishSandwich]

You are right, there should be trees completely dependant on how much water there is.

This is something I'd have wanted the devs to spend their time on.

[Koub]

there should be trees completely dependant on how much water there is.

This is what I have always thought and said, but with no luck so far

[cube]

Trees depend on temperature, moisture (different types of trees have different requirements) and one random noise (common to almost all tree types, you can imagine this as soil quality, or something).
Most of the trees need some moisture, so when you select no water, you basically get desert without trees. The starting area has water, but it is so small that there is a high probability that no trees will grow there because of the third random parameter.

Not a bug.

[SirRichie]

Trees depend on temperature, moisture (different types of trees have different requirements) and one random noise (common to almost all tree types, you can imagine this as soil quality, or something).
Most of the trees need some moisture, so when you select no water, you basically get desert without trees. The starting area has water, but it is so small that there is a high probability that no trees will grow there because of the third random parameter.

If this was true, then why do I almost always get trees in the starting area when I select "minimum" instead of never when I select "only in starting area"? I strongly believe that this is no issue caused by randomness, unless moisture levels are computed globally.

In any way, this thread's intention was not to question the generation algorithm, but to ask if there way maybe a bug. I still believe that this was different in earlier versions of Factorio and I could not find changelog entries which mentioned the change (also see my original post). If the devs are saying that this is not a bug, that's totally fine with me. At no point was I looking for an explanation why it "makes sense" that there are no trees.