AI Main settling continent

[Seravy]

AI Main settling continent is the continent towards the AI is sending the ships loaded by settlers.

Default selection for this is, a random tile on a random eligible continent, which means :
-The continent cannot have any non-neutral non-settler unit of another player
-And it cannot have a non-neutral city, including own.
-The tile selected cannot have a node, lair, etc or city or unit of another player.

That's very restrictive and generally means the AI will only ever send settlers by ships to land which has not been discovered by anyone else.

The good news is, I was able to force a check for the continent having spots where a settler can build a city, so continents already filled with cities by others will not be selected, making that restriction not longer necessary.
The most important part is, continents where it's impossible to build do to a nearby continent having a city too close will not be selected (typically tiny islands).

However, by removing the "no one has city" restriction, it is now possible to ferry settlers backwards : from the continent containing the best race available to the home continent with inferior races. I suspect this was another reason why the AI overlooked territory : Since it was already own, but the continent couldn't produce settlers due to being of an inferior race, the settlers produced elsewhere, but they could only go to uninhabited continents.

Now this however raises a question. Own cities on the continent are fine, but what about cities of other players? Do we want to allow the AI to send to a continent that has enemy cities? Or armies? Note that here, "enemy" refers to ANY player including the AI's allies or people who have no treaty whatsoever with them.
Basically there are 6 continent ratings :
1 - Own armies make up 90%+ of the units on the continent and it contains owned city
2 - Own and other player units both exist and it contains owned city
3 - No owned city present (other wizards might have cities)
4 - Allied city present but owned city is not
5 - No targets (an own large stack found nothing to attack and is leaving)
6 - No targets 2 (There are literally no more neutral or enemy units or objects left on the entire continent)

I don't feel like any of these would make a good condition on settlers destinations... 1 and 2 are obviously good, 3 might be either suicide swarming with enemies or an empty place no one claimed, 4 is, well an ideal place to steal land for allies, and 5/6 say absolutely nothing about the continent aside form it being non-hostile.

Actually...how about this :
Send settler if
-Continent is NOT type 3 (no targets or presence of own city, or presence of ally should mean it's likely safe)
OR
-Continent has no enemy military present (so unclaimed lands still work)

[Nelphine]

Hm.

I've just watched an island (space for 5 cities, 4 if they place badly) that currently has 2 red cities on it, get settled by blue.

Since at least 1 of reds cities has been there for some time, I doubt blue was already en route.

Red and blue do have an alliance.

So I feel like something else is going on, that's allowing some form of settlement? What if they use water walking and not ships? (As both my opponents have water walking.)

My main concern with your suggestion is, does 'enemy military' include allied AI? Because my guess is that is what is causing slowdowns in this game, is that the two have been allied for probably a very long time (strong one is lawful), and so when they both have troops on an island (going after nodes or lairs) neither of them will settle it.

Similarly, early troops guarding a node or a tower will prevent the AI from ever settling a continent with that set up.

[Seravy]

get settled by blue.

Did the settler come by boat?
All of the above only applies to naval transfer. Water walking and flying settlers can go anywhere they want anytime since 2.7x.

does 'enemy military' include allied AI

Yes it does.

and so when they both have troops on an island (going after nodes or lairs) neither of them will settle it.

Yes, that is exactly how the system worked until about 30 minutes ago, and is one of the situations I want to fix.
Unfortunately even my new conditions would not be able to settle this one, but it can at least work if only one of them have the troops there, or one has a city already.
I can't come up with any solution for this unless I specifically change the continent rating system to count allies units as neutral which would...not change the continent's type at all so I guess that's a safe solution...hard to find space for it however.

[Seravy]

I'd like to get the save file, if possible immediately, because if I fix this I have no way to test the solution myself.

[Nelphine]

OK, I'll see what I can do. But, how will you be able to test it with mine? Isn't it too far forward anyway? (Although I like the continent where red has 1 city, and 1 stack of troops. Until 3 turns ago, I had nothing there, blue has nothing there, and.. there's room for at least 3-5 more cities. It's the island closest to his main continent.)

[Seravy]

OK, I'll see what I can do. But, how will you be able to test it with mine? Isn't it too far forward anyway? (Although I like the continent where red has 1 city, and 1 stack of troops. Until 3 turns ago, I had nothing there, blue has nothing there, and.. there's room for at least 3-5 more cities. It's the island closest to his main continent.)

Upload it in the post, the forum should allow that.
All I need is a save file where there is the continent with no one having a city.
Oh wait, I thought it has the continent with no one having a city. Oh, that was just an example not the actual game, my mistake. I guess I'll take the long run and generate one then it shouldn't take too long to hit next turn 100 times with two random AI wizards forced to ally.

[Nelphine]

OK, right now it's fine to water walk to a continent entirely controlled by someone else. Instead of trying to protect a settler being shipped there, can you put a priority system on continents? If it's a type 3, only chose it if no other continents are chosen? That way the AI will constantly be settling something.

[Seravy]

OK, right now it's fine to water walk to a continent entirely controlled by someone else. Instead of trying to protect a settler being shipped there, can you put a priority system on continents? If it's a type 3, only chose it if no other continents are chosen? That way the AI will constantly be settling something.

While that's doable, type 3 continents are unfortunately both the best and the worst possible targets at the same time (as they can be unclaimed territory with no one else around which is far better than sharing it with allies or going towards one of our own continents still having space)

I suppose leaving it entirely unprotected is a solution but...water walking settlers prefer closer locations, and if the location is close enough, water walking and flying units will be there to fight back if the settler is attacked, or to scare away the human player from doing so in the first place (though only if the wizard has Sprites or Nagas unfortunately, nothing else crosses water in the first 50 turns except lizardmen and draconian). On the other hand, ships ignore distance completely, so the settler will be way out of the range of military support. It can just be killed with no immediate consequence to the attacker.