[WIP] U-Boat Killer AI Mod

Nisgeis · 03-24-10, 04:42 PM

Thanks Coldcall. They should get into the vicinity, but the current logic isn't very good - they'll just keep going around where they think you are, dropping DCs. I've got the lost contact procedure working, in that they now will do a spiral search (which was broken in two places, so even if triggered it wouldn't have worked). I'll also have the ammo saving in soon, with a weighting given to how old the contact data is - e.g. as it is now, if the sub was there five years ago, the destroyer will still drop DCs on that spot. Lost contact procedure is hit and miss, as you can travel quite a way from the scene of the crime and they are a bit slow to do a full circle. The 'thermal layer' is also acting like a cloak of invisibility.

Eventually, I will have different behaviours for different situations - e.g. if they are escorting a convoy their priority will be to keep you down and unable to get another shot off, if they are an HK group, they should stay around until you are dead or forced to surface.

All of this depends on realistic battery and CO2, if you are using infinite Battery and CO2, then it will be easy enough to outfox the AI, as you can travel a very long way at 7 knots underwater in an hour. Stay tuned for updates.

Coldcall · 03-24-10, 05:27 PM

Quote:

Originally Posted by Nisgeis

Thanks Coldcall. They should get into the vicinity, but the current logic isn't very good - they'll just keep going around where they think you are, dropping DCs. I've got the lost contact procedure working, in that they now will do a spiral search (which was broken in two places, so even if triggered it wouldn't have worked). I'll also have the ammo saving in soon, with a weighting given to how old the contact data is - e.g. as it is now, if the sub was there five years ago, the destroyer will still drop DCs on that spot. Lost contact procedure is hit and miss, as you can travel quite a way from the scene of the crime and they are a bit slow to do a full circle. The 'thermal layer' is also acting like a cloak of invisibility.

Eventually, I will have different behaviours for different situations - e.g. if they are escorting a convoy their priority will be to keep you down and unable to get another shot off, if they are an HK group, they should stay around until you are dead or forced to surface.

All of this depends on realistic battery and CO2, if you are using infinite Battery and CO2, then it will be easy enough to outfox the AI, as you can travel a very long way at 7 knots underwater in an hour. Stay tuned for updates.

That "missing contact" routine would explain why it takes them a little while to start the active search. Is it on a refresh so they check for eachother every x minutes?

Also forgot to say they were dropping depth charges for a long time but nowhere near my sub.

Nisgeis · 03-24-10, 06:09 PM

That's what the stock behaviour would have been if it had worked, but they never came to investigate. Now they come to investigate, but the next part to get them to spiral search around also wasn't working, I've fixed both parts of that which will be in the next stage, but with the version you have, they'll steam around the last contact point. I'm not going to give any in depth details, as that would probably spoil things :-).

They drop DCs whenever they pass over the last point of contact, in a stupid way, so I will also fix that with some heuristics. I don't want to go mad and change loads at a time, as it will be hard to track what goes wrong. So, I'm keeping it as a progression for the time being, e.g. fix the first part, then the second part.

Trublion · 03-24-10, 11:31 PM

Good Job on the scripts. A few "programming comments" if I may:

In ship-navigation.aix, if I read the code correctly for
ShipHeavyFollowSlowBlind
ShipHeavyFollowCloseDistance
ShipHeavyFollowAcquired

the line
# Ship:GetContactDepth() <= -7.0 and
(Ship:ContactIs(SUBMARINE) or Ship:ContactIs(UNITUNKNOWN) or Ship:GetContactDepth() <= -5.0)....

means that ships will try to reacquire targets no matter if I am submerged or visible. As long as contact is SUBMARINE or UNITUNKNOWN, the depth does not matter. It used to matter, but was commented out.
May I ask the reason, not for sake of argument but more as an enlightenment.

Will-Rommel · 03-24-10, 11:50 PM

Alright, back in my new Lorient base for report :

Run up against a HUGE convoy in the north atlantic, estimated 24-32 merchants carrying war supplies. The escort screen consisted of around 12 destroyers disposed in semi-circular formations at both ends of the convoy + the battleship HMS Royal Sovereign leading the way.

Put 2 fish in the capital ship, she listed badly but made it out at 4 knots, and sank 4 cargos before diving deep to escape the payback.

------ Tech part ------
The destroyers were quite confused because i attacked from inside the convoy with my engines shut down. Some scattered to investigate on the sides, 1 steamed trought the merchants at 34 knots and passed by me without noticing my presence. (submerged at 12m) I heard 2 pings but he was going way too fast to react.

After the battle i surfaced to finish a burning merchant with deck gun. He called a DD back wich steamed on my position full speed ahead. I dived to periscope depth to toy with him, but he didnt seemed to use active nor passive sonar... or maybe they were a green crew? Counted 15 DC drops, incorrect depth and location. (Around 100m from my position, detonation estimated at around 50m deep while i was diving to 120m at this time)

Good experience so far, a bit more fun than stock and more realistic than Ducimus first try. (His escorts were Uber, could track me easy at 180m with engines off)

Coldcall · 03-25-10, 04:47 AM

okay my second encounter was with a small convoy in the Atlantic, protected by 3 destroyers 2 side and one at the back. I hit the convoy from the side, sinking the first in a column of merchants.

I then went to 50 metres, silent running, 3knots, passing under the main body of the convoy.

This time the destroyers reacted very quickly to the attack and "appeared" to home in on the position from which i had fired my torps at the merchant. All three sort of made a beeline for where i had been, and started dropping depth charges.

However escaping was once again easy.

So in 2 encounters now, the escorts have reacted well, which i ahve to say is way better than i experienced in vanilla as they hardly seemed to notice most of the time, unless you sort of crashed into them by mistake.

Finally thre AI is starting to feel like it "could" become a challenge.

Nisgeis · 03-25-10, 05:34 AM

Quote:

Originally Posted by Trublion

A few "programming comments" if I may:
<SNIP>
# Ship:GetContactDepth() <= -7.0 and
(Ship:ContactIs(SUBMARINE) or Ship:ContactIs(UNITUNKNOWN) or Ship:GetContactDepth() <= -5.0)....

means that ships will try to reacquire targets no matter if I am submerged or visible. As long as contact is SUBMARINE or UNITUNKNOWN, the depth does not matter. It used to matter, but was commented out.
May I ask the reason, not for sake of argument but more as an enlightenment.

I'm more than happy for people to comment on the scipt changes, as it's very easy to accidentally put in a logic trap that can never be true, or is always true.

There's a few peculiarities with the contact reports the AI gets. If the AI sees a torpedo, it'll classify you as unknown and guess at a depth. If it sees your periscope or gets you on sonar, it'll classify you as a sub. This was why the AI wouldn't respond beforehand, as the scripts were set to only respond to a sub which meant you had to be seen.

The 'unknown' classification when something goes bang, but they don't see you is also problematic in poor visibiltiy. I fixed the AI response for the convoys in good visibility, but when I went to test in Scapa Flow in bad weather, they still ignored me. I found that if the AI don't see a torpedo, they just hear an explosion, then you get classified as 'Unknown' with a wild depth - in scapa, I was being classified as an unknown at 80 m in the air, so the AI ignored me. So, I removed the depth control as it's not reliable and instead put in sub or unknown or depth. I also added a check for the last time they had a contact with you, so if you are surfeaced in good visibility and they can see you, they will have fresh contact info and it won't try to re-acquire you. If it's foggy or rainy and dark, then they won't be able to see you either, but should still try to get close to where you last were.

Quote:

Originally Posted by Will-Rommel

I dived to periscope depth to toy with him, but he didnt seemed to use active nor passive sonar... or maybe they were a green crew?

Hmmm, they should always have their sensors on, only thing I have found that stops the sensors is the thermal layer, which makes you invisible, but at PD this shouldn't have hidden you. What sort of speed was he doing on his way past?

Quote:

Originally Posted by Coldcall

However escaping was once again easy.

So in 2 encounters now, the escorts have reacted well, which i ahve to say is way better than i experienced in vanilla as they hardly seemed to notice most of the time, unless you sort of crashed into them by mistake.

Finally thre AI is starting to feel like it "could" become a challenge.

Yeah they are still pretty poor

. They will only go over the same area atm, this will change though. Spiral search is next up, but having trouble with role changing...

Thanks for the feedback guys.

03-24-10, 04:42 PM	#1
Nisgeis Ocean Warrior Join Date: Jan 2008 Posts: 2,909 Downloads: 77 Uploads: 11	Thanks Coldcall. They should get into the vicinity, but the current logic isn't very good - they'll just keep going around where they think you are, dropping DCs. I've got the lost contact procedure working, in that they now will do a spiral search (which was broken in two places, so even if triggered it wouldn't have worked). I'll also have the ammo saving in soon, with a weighting given to how old the contact data is - e.g. as it is now, if the sub was there five years ago, the destroyer will still drop DCs on that spot. Lost contact procedure is hit and miss, as you can travel quite a way from the scene of the crime and they are a bit slow to do a full circle. The 'thermal layer' is also acting like a cloak of invisibility. Eventually, I will have different behaviours for different situations - e.g. if they are escorting a convoy their priority will be to keep you down and unable to get another shot off, if they are an HK group, they should stay around until you are dead or forced to surface. All of this depends on realistic battery and CO2, if you are using infinite Battery and CO2, then it will be easy enough to outfox the AI, as you can travel a very long way at 7 knots underwater in an hour. Stay tuned for updates. __________________ -------------------------------- This space left intentionally blank.

03-24-10, 06:09 PM	#3
Nisgeis Ocean Warrior Join Date: Jan 2008 Posts: 2,909 Downloads: 77 Uploads: 11	That's what the stock behaviour would have been if it had worked, but they never came to investigate. Now they come to investigate, but the next part to get them to spiral search around also wasn't working, I've fixed both parts of that which will be in the next stage, but with the version you have, they'll steam around the last contact point. I'm not going to give any in depth details, as that would probably spoil things :-). They drop DCs whenever they pass over the last point of contact, in a stupid way, so I will also fix that with some heuristics. I don't want to go mad and change loads at a time, as it will be hard to track what goes wrong. So, I'm keeping it as a progression for the time being, e.g. fix the first part, then the second part. __________________ -------------------------------- This space left intentionally blank.

03-24-10, 11:50 PM	#5
Will-Rommel Chief Join Date: Jan 2008 Posts: 320 Downloads: 81 Uploads: 0	Alright, back in my new Lorient base for report : Run up against a HUGE convoy in the north atlantic, estimated 24-32 merchants carrying war supplies. The escort screen consisted of around 12 destroyers disposed in semi-circular formations at both ends of the convoy + the battleship HMS Royal Sovereign leading the way. Put 2 fish in the capital ship, she listed badly but made it out at 4 knots, and sank 4 cargos before diving deep to escape the payback. ------ Tech part ------ The destroyers were quite confused because i attacked from inside the convoy with my engines shut down. Some scattered to investigate on the sides, 1 steamed trought the merchants at 34 knots and passed by me without noticing my presence. (submerged at 12m) I heard 2 pings but he was going way too fast to react. After the battle i surfaced to finish a burning merchant with deck gun. He called a DD back wich steamed on my position full speed ahead. I dived to periscope depth to toy with him, but he didnt seemed to use active nor passive sonar... or maybe they were a green crew? Counted 15 DC drops, incorrect depth and location. (Around 100m from my position, detonation estimated at around 50m deep while i was diving to 120m at this time) Good experience so far, a bit more fun than stock and more realistic than Ducimus first try. (His escorts were Uber, could track me easy at 180m with engines off) __________________ -Fighting is a lifestyle-

03-24-10, 11:31 PM	#4
Trublion Watch Join Date: Mar 2010 Location: TAIWAN Posts: 26 Downloads: 119 Uploads: 0	Good Job on the scripts. A few "programming comments" if I may: In ship-navigation.aix, if I read the code correctly for ShipHeavyFollowSlowBlind ShipHeavyFollowCloseDistance ShipHeavyFollowAcquired the line # Ship:GetContactDepth() <= -7.0 and (Ship:ContactIs(SUBMARINE) or Ship:ContactIs(UNITUNKNOWN) or Ship:GetContactDepth() <= -5.0).... means that ships will try to reacquire targets no matter if I am submerged or visible. As long as contact is SUBMARINE or UNITUNKNOWN, the depth does not matter. It used to matter, but was commented out. May I ask the reason, not for sake of argument but more as an enlightenment.

03-25-10, 04:47 AM	#6
Coldcall Chief Join Date: Mar 2010 Posts: 325 Downloads: 42 Uploads: 0	okay my second encounter was with a small convoy in the Atlantic, protected by 3 destroyers 2 side and one at the back. I hit the convoy from the side, sinking the first in a column of merchants. I then went to 50 metres, silent running, 3knots, passing under the main body of the convoy. This time the destroyers reacted very quickly to the attack and "appeared" to home in on the position from which i had fired my torps at the merchant. All three sort of made a beeline for where i had been, and started dropping depth charges. However escaping was once again easy. So in 2 encounters now, the escorts have reacted well, which i ahve to say is way better than i experienced in vanilla as they hardly seemed to notice most of the time, unless you sort of crashed into them by mistake. Finally thre AI is starting to feel like it "could" become a challenge.