AU mod: AI Naval exploration

[Catt]

Still not sure how I feel about barring travel in certain terrains for the curragh -- probably, IMHO, worth some individual play testing.

I would be strongly against barring travel for galleys. My most recent C3C epic game, random map, turned out to be an archi map with no sea passages to other islands -- every trip abroad required an ocean crossing. If galleys couldn't risk the ocean, it would have made for an interminably dull game (whereas the AI doesn't care if the game is dull ). Eliminating ocean travel for curraghs but not galleys would only delay "risking the high seas" until Mapmaking - perhaps not a big change. Until I played with it several times though, my gut tells me an increased movement cost for ocean, but still allowing the chance to risk it, would just "feel right." Again in my current game (not trying to make it, one sample, be determinative in my own mind), even with stock rules it presented an interesting choice of whether to keep pumping out curraghs in the hopes of surviving through the oceans and seas, or cease all suicide attempts until the extra movement point of galleys would increase my odds and hopefully cost less lost shields in the long run.

Catt

[Theseus]

So, if I understand correctly, I would recommend minimal changes for now:

1) Re AI use of Curraughs: Give them 1 unit transport capability.

2) Re exploration: Curraughs - 2mp for both sea and ocean, Galleys - 2mp for ocean.

Let's play with that for a while, and see how it goes.

[donZappo]

1) Re AI use of Curraughs: Give them 1 unit transport capability.

If you only give them 1 unit transport the AI won't actually use them to transport. It's either 2 unit transport if you feel they should be used for settling, or no unit transport for purely exploration purposes. Just give them the load flag without any transport capacity and the AI will build them and use them to explore.

2) Re exploration: Curraughs - 2mp for both sea and ocean, Galleys - 2mp for ocean.

How about 3mp for oceans so that seafaring civs can move 2 while non-seafaring restricted to 1 movement per turn (with galleys).

[donZappo]

I don't know if this will be helpful, or even if it has been done before, but I calculated the sinking percentages for seafaring and non-seafaring civs and the likelihood for them to survive different lengths of oceanic crossings. I did 1500 tests (125 galleys * 12 runs) for a galley in an ocean square for seafaring/non-seafaring. This was able to give me a pretty good idea of their sinking rate. I ran a series of tests to compare the difference between sea and ocean tiles but did not observe a significant difference between the sinking rates for those squares, so I deem the results of this test the "general" sinking rate.

I was hoping that this would give us a basis to make an informed decision in regards to how much movement it should take for ocean/sea travel in order to balance out the advantage that humans get from suicide runs. I don't know what we should consider the "average" suicide run to be, but from the chart it is dramatically clear what kind of advantage seafaring has in this department.

It seems to me that the break-even point for benefits might be galleys surviving 25-20% of the time? That way it would take 4-5 galleys to make it across an ocean which is a decent investment to make early in the game. If that's the case, then seafaring can survive 5-6 turns at sea while non-seafaring only gets 2-3.

Exploring with galleys under the current system seafaring can expect to make it 20 - 24 (!!) squares 25% of the time; non-seafaring only gets 6 - 9. Needless to say that is a *big* difference, and I didn't realize how huge it was until this test. Here's a quick breakdown how different changes would affect galley travel distance assuming 20-25% survival:

Ocean travel rate ---- Seafaring Distance - Non-Seafaring Distance
-------- 1 --------------------- 20-24 --------------------- 6-9
-------- 2 --------------------- 10-12 --------------------- 4-6
-------- 3 --------------------- 10-12 --------------------- 2-3
-------- 4 ---------------------- 5-6 ----------------------- 2-3

In light of this, it appeas to me that the only real balancing thing to do would be to make oceans cost 2 or 4 movement points or at *least* to have sea and ocean movement both cost 2 movement to make seafaring and non-seafaring burn a turn while moving into the ocean initially. If ocean costs 2 movement points then seafaring gets about double odds when trying to cross a large body of water. Also, keep in mind that the longer travel estimate is more likely for seafaring to achieve than for non-seafaring due to an 8% increase in the likelihood of achieving this distance (I couldn't do a straight 25%/20% comparison due to the unevenness of the survival odds - see the chart at the bottom). Ultimately, I recommend 2mp for sea and 2mp for oceans in the AU mod, at least where galley exploration is concerned.

Any changes made to ocean travel is going to affect non-seafaring profoundly while not changing seafaring all that much. Whatever the solution is, I don't think seafaring will have any problems suiciding during the game unless a hard limit is imposed on the oceans. Just keep in mind how changing ocean travel will monopolize suicide galleys for seafaring when deciding what values to use.

[vmxa1]

Those numbers are as good as any I have seen.

[sabrewolf]

nice stats, donZappo!

going from this, it's clear that non-seafaring have a survival rate of 50% and seafaring civs 75%... which - as you chart shows, makes seafaring more likely survive 5 rounds than non-seafarers survive round 2 !!!

in addition: that one extra move of seafarers (eg. +33% (4 instead of 3) or 25% (5 instead of 4)) makes the travellable distance long and a purely human exploit trait (i don't favour exploits)

p(NS) = 0.5^teas
p(S) = 0.75^teas

p : probablity to survive
teas : turns ended at sea


donZappo: were your tests oceanic or sea tiles?

[Tassadar500]

The biggest difference to me seems like 3 turns at sea. 43.67 compared to 11.43 is HUGE when we talk about suiciding.

[donZappo]

Originally posted by sabrewolf
donZappo: were your tests oceanic or sea tiles?

The results posted are for oceanic tiles. After I finished those tests I started a comparison of sea tiles but the results seemed to be exactly the same. From the handful of tests I ran (5-10) the sinking percentages were within 1% of each other for both seafaring and non-seafaring.

[donZappo]

How about if we:

1) Make curraghs seafaring only
2) Give curraghs a transport of 2
3) Remove the ability for seafaring to build galleys
4) Maybe up the cost of the curragh a bit

This would just make the curragh an early galley replacement and help to reduce the overwhelmin advantage that seafaring has in ancient era suicide runs. Here's the previous chart redone with these changes:

Ocean travel rate ---- Seafaring Distance - Non-Seafaring Distance
-------- 1 --------------------- 15-18 --------------------- 6-9
-------- 2 --------------------- 10-12 --------------------- 4-6
-------- 3 ---------------------- 5-6 ----------------------- 2-3
-------- 4 ---------------------- 5-6 ----------------------- 2-3

Then, if you make the ocean cost 2mp you have a much closer balance between seafaring and non-seafaring civs. Either that, or make it 3mp and really bring the two traits closer to each other, but then you really do monopolize suicide galleys for seafaring on any map with a significant amount of water.

Of course, these arguments or only valid if we do indeed want to preserve the suicide tactic exploit for the human. From what I was reading in this thread it seemed like that's what the AU was leaning towards. If you guys want to cut suicide runs altogether then please don't let that part of the debate die in light of other analysis.

[Tassadar500]

The problem with your idea, donZappo is that the changes are quite large compared too other changes. Maybe others view it differently but this is just my opinion as a Civ 3 player not as the AU Dean.

[Catt]

Don't let this conversation drift into any balance issues associated with the seafaring trait -- to my mind, the issue here should be focused on the capabilities of curraghs and galleys; if a resoultion seems appropriate for the naval units, there may still be a further desire for addressing the seafaring trait in some way, but I would hate to focus a decision on naval units based on the seafaring trait's effects.

I don't see any need to provide transport capacity to the curragh - I thought the only reason to explore that option was to stimulate AI exploration? If merely adding the load flag stimulates AI exploration with curraghs, then adding transport capacity to the curragh simply remakes the unit into an entirely different beast.

Without trying to cut off any debate, is my reading of the thread correct in summarizing: (1) adding the "load" flag without any transport capacity results in AI use of curraghs for coastal exploration; and (2) the only remaining balance issue is the utility of curraghs / galleys / caravels for suicide runs?

Catt

[Strollen]

I don't have a strong opinion about this, but making Oceans and Seas cost 2 MP seems reasonable.

My big question is how to you Mod the game so that more advanced ships aren't impacted by the change.

Do you make Frigate, Destroyers etc. ingnore the movement penalty for oceans or Seas or is their some other way of doing it.

[donZappo]

I say the AU makes ocean travel cost 2mp and removes the ability of curraghs to travel in ocean squares. Since the curragh could still travel 10-12 squares before 25% sinking chances start to come into play I believe that this ability to suicide run is imbalanced so early on. I guess it would be tempered by the fact that early game resources would have to be spent on such runs, but I still feel that suiciding should really come into play when galleys are available.

That being said, I still believe that curraghs and galleys should be restricted from ocean travel altogether. Am I right in believing that this idea has been rejected already, or is it still on the table for discussion?

[donZappo]

Originally posted by Strollen
My big question is how to you Mod the game so that more advanced ships aren't impacted by the change.

Do you make Frigate, Destroyers etc. ingnore the movement penalty for oceans or Seas or is their some other way of doing it.

Making later ships ignore movement costs in sea and ocean would be the easiest way of doing it. If you make ocean completely impassable, then you just add the "wheeled" flag to certain ships in the editor then make ocean "impassible to wheeled units." Only wheeled units would then be affected.

[alexman]

Catt, I can confirm that the AI will build curraghs much sooner if they are flagged as naval transports, even if they can't carry any units, and I think this is what we should do. It seems that there is a minimum ground unit requirement for the AI to build a "naval transport", but for a "naval power" unit there seems to be a minimum city requirement as well as a minimum unit requirement.

The AI might still not build curraghs as soon as the human, but that's OK because ground units should be the #1 priority of the AI anyway. It's the best we can do, I think.

As for limiting suicide missions, I'm for 2MP for curraghs in non-coastal tiles, but I wouldn't object to barred ocean travel. I would definitely like suicide galleys to stay, albeit weakened (2MP in ocean).

With reduced sinking chances, there's no stopping a determined human seafaring civ from getting contacts with another continent. We just have to accept it. The question is whether this civ will decide to use curaghs or galleys to get contact. With one fewer MP and double movement penalty in sea tiles, I bet human seafaring players will decide that it's better to wait until galleys, when their own REX will have slowed down and they can afford to spend some shields for suicide missions. Barring travel in ocean for curraghs may not be necessary, but it wouldn't hurt.