Alliances

[Arto]

I want to make a mini mod where backstabbing is impossible and where you will go to war if a faction has attacked one of your allies.

This was my original idea

Spoiler Alert, click show to read: 

So I wanted to make an Alliance mod for M2TW. The idea is this : So you play as Venice. Your diplomat makes with the Turks a defensive alliance (For some turns it depends on how much money you will give). So if Byzantium attack you or otherwise, you are immediatly at war with them and you can't make alliances or other things with other factions. Another thing : So if a (strong) faction is at war with 2 or more factions you can for a coalition against it. If a faction is in a coalition, the faction will be more aggresive than usual and will help you more often until the faction has lost lots of territories or ''please insert here'' . After the faction has lost most of it's territories, those conquered territories will change into a new faction example : You play as Venice and you have conquered lots of Byzantium territories ; you have the option to keep the territories for yourself or to change it into Venitian Byzantium. With this option you will have an defencive alliance for eternity with that faction. (Only Available if you are in a coalition). Oh and one thing : Backstabbing is impossible you can leave and alliance but you never can backstab a faction.

[Azim]

This would be a very large script. It is simply not feasible.
Here's the problem: (In psuedocode)

monitor_event FactionAttacksFaction
  if AttackingFaction == england
    if DefendingFaction == hre
      if not FactionsAtWar france hre
        SetFactionsAtWar france hre
      end_if
      ;all other factions here
    end_if
    ;all other factions here
  end_if
  if AttackingFaction == france
    if DefendingFaction == hre
      if not FactionsAtWar england hre
        SetFactionsAtWar england hre
      end_if
      ;all other factions here
    end_if
    ;all other factions here
  end_if
  if AttackingFaction == hre
    if DefendingFaction == england
      if not FactionsAtWar france england
        SetFactionsAtWar france england
      end_if
      ;all other factions here
    end_if
    ;all other factions here
  end_if
  ;all other factions here
end_monitor

That would make the total number of if statements needed number of factions * number of factions * number of factions, or number of factions^3. So for the vanilla game, that would be 22^3, or 10648 if statements.

[GrnEyedDvl]

It could probably be done a bit cleaner than that, but it would still be large. Actually 10k events isnt terrible, after all there are garrison scripts out there with 200k+ lines of code.

But I wont be writing it.

[Arto]

Which .txt is that?

[GrnEyedDvl]

It would go in the campaign_script.txt

[Arto]

How do you actually do that?
I've hardly any experience with this kind of scripting.

[GrnEyedDvl]

I have quite a bit of experience scripting, and I never solved this issue to my satisfaction. There are a lot of roadblocks. If you are truly interested, then you need more than a basic understanding of scripting.

I have posted some of my research in a similar thread if you care to read through it. Its not all in code so you should be able to follow the logic fairly well. Maybe if we get enough people with ideas together, both scripters and non scripters, we can work out something decent.

http://www.twcenter.net/forums/showthread.php?t=187424

[alhoon]

There's a line in descr_campaign_ai_db.xml. About trusted allies going to war.
I have used it in my mod. It doesn't do exactly what you want though.

Anyway, it's the closest and easiest thing to do.

Use Lusted's AI for preventing backstabbing of allies first.

Then change the descr_campaign_ai_db.xml
as follows:

<trusted_ally_fs_threshold float="-1.0"/>
<trusted_ally_target_fs_threshold float="-1.0"/>
<trusted_ally_target_human_fs_threshold float="-1.0"/>
<trusted_ally_gs_threshold float="-1.0"/>
<trusted_ally_target_gs_threshold float="-1.0"/>
<trusted_ally_enemy_auto_war bool="true"/>

I have used it in my mod (Lands to conquer: Andy's modifications) and it works.

That way everytime the AI declares war to it's allies enemies. Even if these allies are pathetic scumbugs.

HOWEVER: the Player won't go to war with his allies enemies automatically.