The AI's Biotic X-Ray Vision through certain objects: A bit of research on the matter

[maturin 12]

That's unfair. You used your Biotic X-Ray Vision.

I wonder if people crying about AI tried playing with AI leader?

When he orders you to engage the enemy you can see a red target - either where AI thinks the enemy is or if he sees the enemy directly - on the enemy itself. When the enemy starts running and runs behind a wall or bush the red target continues to move in that direction with the last known speed of the enemy and it often turns out that it points at nothing when reaching the other side of the wall/bush

Then it either disappears because AI leader can no longer see the enemy or if he spots that enemy in time again - it jumps to that enemy's position.

That's how AIs act in this game. There is no X-Ray vision. This is called logical behaviour. Just because you ran behind some bush doesn't mean you suddenly became invisible and teleported into some parallel dimension where AI cannot engage you.

Exactly.

However, if you play with an AI team leader, you will notice many situations over time where the system glitches out and enemy units are called out through entire villages and hillsides.

These aberrations never seem to occur with well-defined objects like single buildings and bushes at close range (where it matter most, I should add), but they do make people think that the AI cheats more generally. I hope BIS is aware of this issue, but I rather doubt it, seeing as making a ticket for it is impossible.

[metalcraze 290]

However, if you play with an AI team leader, you will notice many situations over time where the system glitches out and enemy units are called out through entire villages and hillsides.

I tend to play missions with AIs relatively often and I haven't noticed any of these issues. In fact I think the last time I saw one like that - it was in one of older AA2 versions.

If AI in fact saw enemies through bushes nobody would've been surviving a single encounter. It would've been over in seconds. And f.e. when I played coops with CiA we managed to survive for hours (and those guys don't even use respawn).

I've played a mission today where between me and enemy AI MG gunner there was a wall of bushes. But not a single time he tried to shoot me or anyone else through them. In fact he was engaging the guys he could see (this was very easy to notice due to tracers).

And I was firing through those bushes at him. Am I cheating and "seeing" him through bushes?

I think the problem here is that people play arcade shooters too much where you wipe out enemies in hundreds due to a very stupid AI that just stays in one place waiting for you to kill him and don't die due to how easy they are nowadays. And then when they encounter a game where AIs try their best to be just as good as a human player - it's suddenly a huge tragedy.

[pooroldspike 129]

As I said earlier, it's a perfectly normal real-life tactic to fire into light cover if you suspect an enemy is in there even though you can't see him, it goes by names such as "searching fire", "suppressive fire", "speculative fire", "area fire" etc.

In fact I posted a video in this very forum last year showing US marines plastering a hut with small arms and killing the unseen terrorist inside, and drew a 3-month ban for posting "explicit content", ha ha..:)

[dmarkwick 261]

Once alerted to your position, the AI will be tenacious in tracking you down using last known, predictive, and sound information.

Pretty much like it would be in real life I expect. Someone being hunted down usually is found.

However, AI will not magically see you if they don't have any compelling reason to see you, like you taking pot-shots at them :)

[pooroldspike 129]

Sometimes the enemy AI can be hopeless at spotting you, as these two recent tests indicate.

In the first test I crawled around prone in clear view of the enemy for over a minute and they never spotted me, and in the second test I was standing in plain view of them at 300metres and they couldn't spot me!-

http://www.thefewgoodmen.com/thefgmforum/showthread.php?7702-Some-general-spotting-tests

[walker 0]

Hi all

I direct you all to the ArmA II Mythbusters thread.

http://forums.bistudio.com/showthread.php?t=103866&highlight=myths

I refer you too

MYTH. The AI Cheats and can see me when it shouldn't and when I would not be able to see it

and

MYTH: The AI sees through bushes!

Kind Regards walker

[pooroldspike 129]

I agree that carefully setup tests are the way to go, but the fly in the ointment is that tests might only be valid for certain versions with or without certain mods, patches and addons etc.

For example my tests are done with vanilla Combined Ops 1.08/1.57, so whether they're valid for anything else I just don't know..

ASSORTED TESTS etc- http://www.thefewgoodmen.com/thefgmforum/forumdisplay.php?123-Armed-Assault-II

[Beagle 684]

Old and simple rule...when using mods that change your game don't blame BI.

I broke OFP and ArmA so many times with mods that I stoped using them at all for now.

[metalcraze 290]

Sometimes the enemy AI can be hopeless at spotting you, as these two recent tests indicate.

In the first test I crawled around prone in clear view of the enemy for over a minute and they never spotted me, and in the second test I was standing in plain view of them at 300metres and they couldn't spot me!-

http://www.thefewgoodmen.com/thefgmforum/showthread.php?7702-Some-general-spotting-tests

Default BIS AI has an eternal problem with a spotting range since OFP.

That's why I use Zeus AI that makes them detect you at longer, human-like distances.

[maturin 12]

I agree that carefully setup tests are the way to go, but the fly in the ointment is that tests might only be valid for certain versions with or without certain mods, patches and addons etc.

For example my tests are done with vanilla Combined Ops 1.08/1.57, so whether they're valid for anything else I just don't know..

ASSORTED TESTS etc- http://www.thefewgoodmen.com/thefgmforum/forumdisplay.php?123-Armed-Assault-II

I think you can be confident that no mod is going to interfere with the viewblocking properties of a bush, nor give the AI clairvoyance without deliberately doing so.

Of course all tests should be carried out without mods and the most up-to-date software, but they should also distinguish between immutable qualities (such as the lack of X-ray vision) and things which can be adjusted, such as gunshot localization and spotting distances.

[Neopas 10]

In the game, when we see an enemy run behind a bush, we fire through the bush and get him even though we can no longer see him, that's a standard real-world tactic too.

So it's only fair that the AI enemy does the same to us isn't it,

Exactly.Why not?

However, if you play with an AI team leader, you will notice many situations over time where the system glitches out and enemy units are called out through entire villages and hillsides.

I am not saying that it can`t be like that sometimes,however there are cases ,when those enemy units are detected by other ,same faction ,units and the information is passed to a friendly AI leader further away but available to engage.Depends on mission design.

My general impression is that AI ,while not perfect,behaves somewhat consistent so it`s useful.

You can`t actually shoot at enemies and expect not to be detected just by relocating around them in 200-300 meters radius,even in a gh.suit, but that`s not a bug in my book.

[pooroldspike 129]

I'M SHAKIN' IT HERE BOSS!

My 'Bushes as concealment' test, (vanilla Comb Ops 1.08/1.57, Regular difficulty)

Mano a mano: A blue (player) and a red Rifleman -

Blue guy runs towards standing Red guy (circled)

Red sees Blue and drops to a crouch and starts shooting-

Red has now gone prone and keeps firing as Blue runs on-

At last Blue makes it behind a bush and the shooting stops. (I waited a good 2 minutes but Red never fired again)

And I held Blues fire throughout the entire test-

Edited April 7, 2011 by PoorOldSpike

[pooroldspike 129]

Another view. Note the range is only 64 metres and the bush is only a fairly scrawny thing-

Another view. Like I said, Red completely stopped shooting the instant Blue went behind the bush-

I decide to taunt Red, so I move Blue sideways out into the open, and Red INSTANTLY BEGINS FIRING-

So I run Blue back behind the bush but Red KEEPS FIRING THROUGH THE BUSH, ouch that hurt-

And the fat lady sings..

CONCLUSIONS- A bush will sometimes provide cover, and sometimes it won't. Early In the test we clearly saw Red cease fire when Blue ran behind the bush, but later Red did NOT cease fire and shot straight through the bush.

I suspect there's an inbuilt 'random' factor within the game coding to make things less predictable and I have no beef with that, as it means we have to expect the unexpected during play.

Other factors may also be involved, such as weather/visibility/difficulty level/how many enemy eyeballs are on the lookout for you/whether you're standing,crouched or prone, etc.

PS- or maybe some areas of the bush itself are thicker than others (undetectable to the players eye) and will provide concealment, whereas if you move a few inches either side, the foliage is not so thick and you get zapped..

Edited April 7, 2011 by PoorOldSpike

[walker 0]

Hi all

First up a bush is Concealment NOT Cover.

http://community.bistudio.com/wiki/ArmA_II_Hints_and_Tips#The_difference_between_cover_and_concealment

Cover is something that stops bullets by being so thick and dense or hard that the bullet cannot get through, Fat Stupid Generals is a good example.

Concealment is something that prevents you being known about.

A bush is concealment!

But all the concealment busters apply with AI as they do with humans.

From Peek-A-Boo behind the blankie to making a noise and any bush seen firing bullets at me gets it full auto and all its pretty leaves ain't gonna stop my rounds hitting what ever is behind it.

Why anyone would think the AI does not know you are behind the bush in such circumstances is down to people playing games with stupid AI like COD.

I have known about Peek-A-Boo behind the blankie since I was about 7 months old.

As to the AI loosing track of you it is down to knows about values and where that knows about values has your position tracked too.

Once again see the ArmA II Mythbusters thread where there are several missions designed as experiments test this along with videos of the test results. Click on the spoiler links to see the explanations.

http://forums.bistudio.com/showthread.php?t=103866

Kind Regards walker

Edited April 7, 2011 by walker

[old_painless 182]

You are obviously quite experienced in this issue. Is it possible for a modder, who creates new bushes and shrubbery, to somehow set the concealment effect/value of a certain object too high or too low? Ie. suddenly the bush is transparent, or too non-transparent.

And can we absolutely sure that such a problem does not apply to any of the stock bushes ?

Does that make sense - does each bush-type have its own level of concealment?

[metalcraze 290]

PS- or maybe some areas of the bush itself are thicker than others (undetectable to the players eye) and will provide concealment, whereas if you move a few inches either side, the foliage is not so thick and you get zapped..

No I think when you ran behind the bush AI 'lost' the track of you, but then when you appeared and went just 2 m back and forth it still managed to guess your position so he killed you through a bush.

If anything the fact that it lost you when you quickly ran behind a bush doing some "longer" distance means that BIS should only make AI better and more eagle-eyed, not dumb it down. The silliest bit however is that AI didn't engage you through a bush even not knowing your exact position behind it. Human players always fire a few rounds into bushes when they see a guy running into them.

But I hope that test will help our crybabies understand that them getting killed isn't a problem with AI, they need to learn to play the game.

Edited April 7, 2011 by metalcraze

[maturin 12]

The AI usually does engage through bushes, but only if they saw you vanish behind it. They should only be used in combat if other people in your unit are being targeted and you think you can shield yourself from a portion of the battlefield.

---------- Post added at 09:16 PM ---------- Previous post was at 09:13 PM ----------

And can we absolutely sure that such a problem does not apply to any of the stock bushes ?

If someone wanted to take the time to examine the files, yes.

Does that make sense - does each bush-type have its own level of concealment?

Each bush has a complex invisible model with viewblocking properties. It is of course less complex than an actual bush, often somewhat smaller and doesn't look like actual foliage, but it's still an awful lot of spiky polys, whereas Arma just used solid diamond shapes.

[walker 0]

Hi all

Whether the AI sees you is a complex set of mathematical calculations that result in what AI the knowsAbout an entity.

An entity is any vehicle and soldiers are a vehicle of the soldier class. An entity can be aither AI or player.

Groups have group awareness; to save on calculations, and to mimic humans passing around a contact report. Groups also communicate with each other, this mimics what humans do over radios.

Visitor

Terrain and terrain clutter like bushes are two separate things. Terrain clutter are objects made in LINDA BIS's vegetation editor, or Oxygen, BIS's object editor, that are then added to the terrain in Visitor BIS's Terrain editor.

LINDA

LINDA has not been released to the the community.

http://community.bistudio.com/wiki/Linda

This is probably because it is very advanced and its products can be sold separately as sevice, and the tool can be sold at a premium to early adopters. That it is part of the business model that provides competetive advantage and that BIS are keeping back to prevent competitors from reverse engineering it. And because as one of the newer tools, it is not very user friendly yet.

There is detailed information about LINDA here

http://pro.bistudio.com/index.php/services/linda-tree-generator.html

And at the top of the FAQs is an explantion of why it is not released:

http://pro.bistudio.com/index.php/services/linda-tree-generator/frequently-asked-questions.html

Oxygen

So if a community addon maker wants to make a vegetation object they are going to make it in Oxygen. Which is not going to be as good as LINDA

Here is a tutorial by Moncalb about building an object in Oxygen

http://community.bistudio.com/wiki/Mondkalb's_Addon_Tutorial

There is a discussion about making vegitation in here Oxygen.

http://forums.bistudio.com/showthread.php?t=94579

So can a badly made bush not work at blocking AI "vision"?

It is the LODs and material that determine the view blocking ability of an object/addon; for instance glass is see through for both AI and humans. These are defined in the LODs and the config of the addon. The complexity of LODs and materials in LINDA is superior to Oxygen so it is probable that a bush generated in Oxygen is not as effective.

Also if a LOD or config value in a terrain clutter object/addon in Oxygen is incorrectly defined then it may not perform as it should in blocking AI lines of "sight".

If the author of a terrain uses an incorrectly defined addon then it follows that the clutter object may not block the AIs lines of "sight" in the simulation.

Or short answer Yes!

Kind Regards walker

Edited April 8, 2011 by walker

[pooroldspike 129]

ANOTHER BUSH TEST

(vanilla Comb Ops 1.08/1.57) Reg difficulty

This time I'm going to make Red guy move (standard default type movement) very close past Blue guy's bush-

Okay, Blue is behind the bush as Red comes over the hill-

Red is running in a slightly zig-zag pattern and there's no sign he's spotted Blue-

Getting closer-

And closer-

[pooroldspike 129]

And at last Red spots Blue and blows him away.

I held Blues fire for the whole test.

CONCLUSIONS-

The bush gave Blue guy total concealment even though he was standing all the time.

He was only spotted when Red came round the bush pointblank.

Perhaps running degraded Reds spotting abilities, I don't know.

Also perhaps more attackers would have had a greater chance of spotting Blue.

[NeMeSiS 11]

Perhaps running degraded Reds spotting abilities, I don't know.

AFAIK it does, but in this case you where completely behind the viewblock lod so it didnt matter, the AI cannot see through it, like you cant see through a concrete wall.

[pooroldspike 129]

And maybe Blue was harder to see because he was in the shadow of the trees, the permutations are endless.

[NeMeSiS 11]

And maybe Blue was harder to see because he was in the shadow of the trees, the permutations are endless.

Still wouldnt matter, he is behind an object that blocks AI view so there could be spotlights aimed at him, animals running away and a civilian doing the ALICE 'Oh god no help its enemies next to me!' AI behavjour right next to him, red cannot see through.

[SteveJA 12]

Another test to prove that the AI cant se through is to get blue to fire at red, blue then gets behind the bush. Once behind, teleport blue somewhere and your'll see red start pumping lead into the bush. :)

[pooroldspike 129]

Another test to prove that the AI cant se through is to get blue to fire at red, blue then gets behind the bush. Once behind, teleport blue somewhere and your'll see red start pumping lead into the bush. :)

If by 'teleport' you mean move away,I tried it a couple of times but the instant Red sees Blue he usually starts shooting and kills Blue before he can get clear.

No sweat, I think we've all pretty well established that-

A- If you're stationary and non-firing, the enemy usually DOESN'T have x-ray vision through bushes and won't shoot at you.

B- But if he saw you go behind the bush, or if you're shooting or wriggling around, there's a good chance that he'll fire through the bush and get you.