(AI) More flaks and fighters!

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(AI) More flaks and fighters!

#1 Post by Oberlus » Wed Jul 18, 2018 11:55 am

Playing 0.4.8 RC2.

In my last game, Sly, 200 systems 9 AIs, I thought I was going to lose. One of the AIs, Etty, was very good at conquering some good planets early and I think that gave it a good push. By turn 200 it had 10x my estimated military strength, 5x production and 5x research, 50% more population. My doomstack was 3k damage (with fighters) and the AI had several 3k+ stacks and one of 12k+ damage next to the 9k dommstack of another AI (thanks to that I wasn't dead). I was asteroids the AI robotics. I was able to keep a hit and run strategy while I was pumping out more and more scattered asteroid carriers (4 fighters bays, 6 launch bays, 3 DRs, rest armor 30). The main forces of the enemy were self-grav and titanic with black shields and half armour 40 half DRs. When I had nearly the same damage (not counting fighters) than the marauding AI stacks I began attacking them directly, and the results were disastrous for the AI. I was losing 2 of 20 ships and the AI full stacks priced twice my stack. The AI knew about my composition (I was accumulating ships for more than 100 turns) but didn't adapt its own.

I've made some numbers (made before me by other forum contributors that I can't recall, maybe EricF) and the half-SR half-armour strategy is a no-go against fighter focused empires. If you substitute half the DRs (in a Titanic with 8 DRs and 8 armours, this is 4) for flaks, with the same resources you get +45% more ships, +45% more structure, -38% SR damage but you can shoot down the most of the fighters on second round. In the end, with less DRs, it inflicts more damage (via removing the fighter cannon-fodder on turn 3).
The AI had some fighters on its stacks but way less than me (1:10). Obviously more interceptors and/or fighters would be also a good counter for figther-focused empires. The flaks-instead-of-some-DRs is just the minimum you must do to adapt against fighters.

At the same time, I think it may be a waste of AI team efforts to try and consider this since it is likely to vary in the future, since there are many plans about rebalancing and revamping different systems of the game, including weapons.

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Re: (AI) More flaks and fighters!

#2 Post by Dilvish » Wed Jul 18, 2018 2:29 pm

Currently, the AI assesses its ship designs against a 'standard enemy' from what it has observed. It updates that over time as it runs into enemy ships, but it's currently always choosing a single one of the enemy ships that it runs up against, to serve as this 'standard enemy'. It does very much sound like it's about time for us to have it instead compile a small set of standard enemy ship designs. And then the main rating for its own designs would generally be taken as the average combat rating against those various enemy designs.
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Re: (AI) More flaks and fighters!

#3 Post by Morlic » Wed Jul 18, 2018 7:42 pm

I think our current fighter assessment code just isn't very good. When I wrote it, the fighter system was still in its early implementation stage and subject to constant changes and I probably had some misconceptions as well. Now that the dust has settled and we have some more experience regarding fighter impact (and the current AI behavior), we should probably revisit and update that code.

Some stuff which needs to be improved:
* Need to consider cost of enemy ships - if the enemy "standard design" costs a quarter of our carrier, we should probably expect 4 times the shots
* Need some minimum structure to be likely to survive in 1st bout (i.e. have more effective structure than enemy deals damage)
* We should use proper statistics to handle how many fighters are shot down and how many shots are blocked by them (for now just assuming weighted enemy shots)
* We should consider enemy fighters - also for regular designs.

In late game, I think we underestimate the usefulness of fighters significantly.
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