Hidden units: Invisible to AI too?

[Servius]

I'd love to get a dev's thoughts on this, but who knows how often they check the threads here. So, short of that, I'd love to hear anecdotal reports if you have any. Here's the question:

In previous TW games, on the battle map, you could hide your units in the woods, but the AI knew they were there. My most vivid memories were back during MTW, where if you hid a unit in the woods, the AI would send one cavalry unit at a walking pace right for it. Once the hidden unit's cover was blown, the rest of the AI force would move up.

I can't personally recall such obvious evidence that the AI knows where hidden units are from RTW or M2TW (my memory of both games is pretty fuzzy), and I can't recall having seen anything that obvious in ETW. ETW also added a lot more units with hiding abilities. Some units (like Rangers) can apparently move unseen on the campaign map, but are seen when they move on the battle map. Other units (like Native American Bowman) can move and stay hidden on the battle map, so long as they walk and don't run. They can even fire their bows and remain hidden. Then there are many units who can hide in just woods, or woods and tall grass, or woods, tall grass, and short grass, etc.

With all this potential for strategic (camp map) and tactical (battle map) trickery and cleverness, I want to know if it actually works against the AI, or just against human players.

>>>>>>>>>>>>>>

Also, in a related but slightly different area, it seems that Generals have no ability to hide. I get the reason for that, but what it means is that you can't have a fully-hidden force on the camp map unless that force lacks a general to lead them. If this is true, then that means that the 'paths less trodden' ability simply keeps players (and maybe the AI) from knowing the full size of stacks on the camp map. Because of the general, they'll know where the stack is, but because of 'paths less trodden' they might not know the full size of the stack. Is this a correct understanding?

[Prussian to the Iron]

in m2, RTW, and ETW, i have never once had a hidden unit that was not attacked by the enemy (on the battlemap, i dont know about campaign map), despite being perfectly camoflauged, unless I was playing on easy difficulty for campaign and battle.

so basically: no. units on the battle-map are not invisible to enemy a.i.

[FactionHeir]

They know where they are hidden in every title.

In ETW, they just walk really slowly up to your hidden units if they are ranged and then run as soon as they get within your firing range, even if your units are not on fire at will. In that, the AI will make a point of going after your hidden units first in many cases.

[Dreadnought2]

I beg to differ...

I've had units that I've moved forward into woods and the AI's army has moved to counter the move...my unit stops in the woods but takes a few seconds to 'hide' so the enemy keep advancing...then my unit becomes hidden and the AI troops immediately lose interest and head off towards my non-hidden units. If they knew where hidden units are, why would this happen?

I've used this with good affect in fort attacks where there are woods between the starting point for my forces and the fort. I've run some of my infantry into the woods on the flank of the fort and the enemy relocate on the walls to counter the move, then my troops 'cloak' in the trees giving them time to recover for the final move towards the fort and the AI troops happily turn around and head back to look at my other troops cheerfully demonstrating in front of the fort.

I've also seen some very good ambushes by light infantry and similar units. Going by the AI's reaction to being caught in the open by these troops, the AI simply had not known they were there.

Cheers,
Dreadnought2

[Slaists]

They know where they are hidden in every title.

In ETW, they just walk really slowly up to your hidden units if they are ranged and then run as soon as they get within your firing range, even if your units are not on fire at will. In that, the AI will make a point of going after your hidden units first in many cases.

Hmm. My experience is quite different. Sometimes I even use a "trap" whereby I have 4 native american musketmen hiding in long grass or scrub away from my main body of my troops. I'd run a single cavalry unit towards the enemy baiting their cavalry out. Running the bait cavalry back through the hidden musketmen would result in total annihilation for the AI cavalry, so, it seemed, the AI could not see the hidden units.

However, I have to note that this worked better before the 1.3.1 patch. CA has explicitly stated the the 'spot view' range has been increased for many units (especially scout types and cavalry). So, post 1.3.1, your hidden units are spotted at farther distance. As a result, one needs to pay closer attention to the terrain where the units are hidden. The 'spotting' distance has terrain adjustments. It's hardest to spot units if they hide in forest; a bit less hard if they hide in bush/long grass, etc., but easiest if they hide in plain view (some unit types can do that).

As to that walking/running part. I believe, what's involved is the AI walking towards its target (as they usually do); spotting your hidden units at the new increased 'spotting range' and then closing in for the kill.

[Prussian to the Iron]

could it perhaps be that, at least in E:TW, certain units (like native indian units) are invisible as they should be, whereas others (like pandours, rangers) are only hidden from the A.I. at easier difficulty levels?

if that's not it, then I cannot explain why some people have the A.I. seeing their supposedly 'hidden' units, whereas others have them behave like they should (at least in regards to hidden units)

[Dreadnought2]

It must be just the fog of war...
Sometimes it works, sometimes it doesn't - just like real life!
Cheers,
Dreadnought2

[Dreadnought2]

In regard to the pandours (who can walk stealthily), I've walked them forward within arty range but outside small arms range without any reaction or arty fire from the AI. As soon as they enter AI-spotting range, they're no longer shown as 'hidden' and the AI starts reacting to their presence.

I've also used this sort of tactic to draw away their cavalry from the main body of the enemy to allow for a flanking attack by my own cavalry. Move a unit stealthily forward and off to one flank of the enemy until you want them to react, then run them into nearby woods (the AI suddenly reacting and sending cavalry towards the 'bait' unit and away from their own infantry and arty) then halting the infantry so they hide - preferably before the enemy cav get within spotting range. The enemy cav are then out of position and hopefully a bit tired from their little run if they do manage to get back to the main body.

Remember too that some light infantry type units can also hide while garrisoned in buildings.

Cheers,
Dreadnought2

[Slaists]

could it perhaps be that, at least in E:TW, certain units (like native indian units) are invisible as they should be, whereas others (like pandours, rangers) are only hidden from the A.I. at easier difficulty levels?

if that's not it, then I cannot explain why some people have the A.I. seeing their supposedly 'hidden' units, whereas others have them behave like they should (at least in regards to hidden units)

I suspect, people are confusing the AI really seeing the hidden units with the AI going for spots that it would go to anyway, even without knowing there were hidden units. For instance, players are likely to hide units in trees on the flanks of their line. However, the AI is very likely to go for the flanks of the player's position by default. So, it might seem, the AI "knows" there is something to go for in the trees. However, the truth of the matter in this case would be that the AI was just executing the standard flanking maneuver and started running towards the hidden units after its cavalry spotted them.

[Prussian to the Iron]

again, I'll have to run some tests to test this. will be harder though.

[Slaists]

again, I'll have to run some tests to test this. will be harder though.

Hide the units in a nonsensical spot far away from your main line. If I do that (for example, to hide cavalry that's supposed to rush towards the AI artillery behind its lines) then VERY RARELY the AI runs into them. Of course, you might encounter the odd case when the AI does the wide sweeping cavalry 'along the map's edges' maneuver to charge your rear, and, as a result, runs into the forces you have hidden.

[Prussian to the Iron]

I'll try that, and every time I'll ever so slightly move the hiding units a bit more to the center to see if the enemy will attack them.

of course, they could just be attacking hidden units and making it look like they are makig a logical decision...

[antisocialmunky]

The only successful battlefield ambush I ever mananged was in STW with 2 Yari Cav hidden in the woods flanking the whole enemy army :) Felt so good about that.

[Sebastian Seth]

This hapened in M2TW: I was defender in siege and spain was attacker. I runned with two hashasims right out of the front gate and whent to two little bushes where I got the hiding mark. The AI played normal and send the siege ram and ladders forward full speed. I took them both out with hashasims and then the spanish charged my hashasims to oblivion.

But AI didnt react to them when they where hidden.

[Prussian to the Iron]

This hapened in M2TW: I was defender in siege and spain was attacker. I runned with two hashasims right out of the front gate and whent to two little bushes where I got the hiding mark. The AI played normal and send the siege ram and ladders forward full speed. I took them both out with hashasims and then the spanish charged my hashasims to oblivion.

But AI didnt react to them when they where hidden.

I think that is more because the A.I. was more focused on taking the city then it was on fighting your hashashim. This sometimes happens, even with non-hidden units coming out of a city to attack the enemy; they dont react, then they get destroyed as they climb the ladders/siege towers and get hit from both sides.

[Veho Nex]

Hide the units in a nonsensical spot far away from your main line. If I do that (for example, to hide cavalry that's supposed to rush towards the AI artillery behind its lines) then VERY RARELY the AI runs into them. Of course, you might encounter the odd case when the AI does the wide sweeping cavalry 'along the map's edges' maneuver to charge your rear, and, as a result, runs into the forces you have hidden.

Rare? They seem to do that in every battle unless I keep my arty smack dab in the center with my main force on both sides...

[Didz]

My own experience suggests that they are hidden. However, its worth noting that certain terrain cannot provide enough cover to keep them hidden, and I've certainly been caught out as a result of wandering into an area of 'open ground' and getting spotted. Its not always easy to tell on the TW maps what the terrain graphic's are meant to represent. Crossing a road is certainly guarantee'd to get your men spotted I know that.

[InsaneApache]

Crossing a road is certainly guarantee'd to get your men spotted I know that.

Not all the time. Climbing fences/walls/roads used to show up my long rifle men until I worked out the knack. Face them up square on and they climb/cross/leap across these obsticles without exposing their presence. I'm just about to take Bogota with them and it's only 1800. I love 'em.

[Servius]

There's another potential variable I've noticed in some of your posts. There may be a difference between units that are hidden by your initial placement (before the battle actually starts) and those that move to cover and become hidden after the battle starts.

From all the posts above, I've seen a trend where the AI seems to know exactly where pre-placed "hidden" units are and sends a scout to un-hide them, vs. units that become hidden only after the battle starts, which the AI seems to ignore.

Prussian Iron, if you're running tests, you may also want to include this as a variable you test.

[Prussian to the Iron]

will do!

[A1_Unit]

The AI hasn't found my hidden units yet...

[Kantalla]

I have had good success with light cavalry in the woods waiting for the enemy line to pass and then pouncing on their artillery. From what I have seen the AI doesn't know exactly where your troops are.

[Prussian to the Iron]

I hate it when people come and post in topics that have been dead for over a week. pisses me off when it appears in my User CP.

[Servius]

Perhaps it should piss you off more as this thread does not yet contain the results of your research!

It seems like a broken feature if the AI can ignore it. If it's not already in, General units should gain a trait that allows them to also go unseen if they lead a stack entirely made up of units that cannot be seen on the camp map.

[Prussian to the Iron]

yeah, sorry bout that. I've been really busy lately, and my computer time is limited. figured it would be better if I spent my hour a day having fun on Mount and Blade or BFME1 and leting someone else do it.

hey you're in Chapel Hill? I think my mom had my last little brother there!

[Servius]

:-) Haha. That was an oddly-worded sentence. You mean your youngest brother was born here? That's awesome. It's a fantastic place to live.

I was also meaning the bit about the abscent research data with a smirk on my face. I'd love to have hard data instead of just recollections, but it's not like anyone's compensating you for the research. If it happens, it happens. :-)

[Kantalla]

Thanks for the warm welcome I figured content on the front page was still current, apologies if it was a bit old.

As previously hinted at, I have had a number of battles with light cavalry concealed in trees, which have jumped on their artillery when the main line has gone by. Usually enemy cavalry from their main line will try to intercept, which if I've timed things right will be too late.

I have tried out some tests to try to verify my suspiscion that the AI doesn't know where your hidden units are. Playing as Sweden on normal difficulty, I took a unit of demi cannons from Ingria to Riga, and then took the entire force in Riga to besiege Jelgava. I waited for the defenders to rally, so I would be on the defensive for testing the AI against hidden units.

Essentially each test had the cannons sitting some distance away from the rest of my army. Hopefully the AI would see the undefended cannons as something to take out. The cannons were set to not fire at will to avoid that disrupting the hidden unit testing. The battlefield has a large forest in the centre of my deployment zone, with a small one off to the left of the zone. Here are the results of a few replays of the battle:

1) Cannons deployed in the left forest, with rest of force to the right of the deployment zone. Courland ignores the cannons and advance to the remainder of the force. At this point I was thinking this was looking like the AI couldn't tell the cannons were there.

2) Similar to the first, but this time the cannons deployed just outside the left forest. Just like the previous battle, Courland ignores the cannons and heads to the rest of the force. I guess the AI was making the same decision I would make - that the fixed cannons are too far away to be a threat, so it is better to take out the rest of the force.

3) Cannon deployed in the central forest, rest of force to the right. Again Courland ignored the cannon in their movement, but when a unit got close about 1/3 of their army switched over to take out the cannons. I think this was just a touch too close for Courland to advance past without engaging the cannons.

4) Cannon deployed just behind the central forest, rest of force to the right. This time Courland sent three units toward the cannons and the rest of their force at my main force. There was a noticeably different behaviour from the AI when the cannons were hidden (and in range) to when they were in the open (and in range).