What's wrong with the second bush? You can see him, so he probably can see you too?

The problem is that he can see you like the bush is not there at all (no obstruction to his aim, nor the speed at which he spots you). Sure, you can see him at that distance and perfect weather conditions (only his right elbow, and part of NVG's though), but in real game from some distance, good luck with that.

You could argue that the player can do that as well (hide in the same bush and peak through it), but by the time you manage to spot something through those cracks (moving left/right to get a good angle to see anything at all), you will be dead long before you even spot him.
The AI doesn't see that part of the bush at all, he will have no problem spotting you from 100-200m and identifying you as hostile (and he will identify you as hostile almost instantly - since the bush doesn't even exist for him), even though that is not possible for human players at all, not even from the range I recorded the video - you couldn't identify him as hostile based on that elbow - and that's maybe 10m range max.

As you can see on the second bush, branches are covering his head completely. Unless the devs can simulate AI seeing only through those tiny cracks of the bush, only when it's not covering their head, and have some impact on how fast they can identify/can they identify at all, bushes should completely block their vision.
Maybe make that bush denser as well (falls into "nice to have category" I guess) . Though I don't really mind if they don't, because even if players spot AI in that bush, they don't shoot on sight, since there is no way for a player to identify is it friendly or enemy.

I checked the second bush, and you're right; it's way too see-through for AI. Not completely invisible though. It just wasn't that obvious in your video, in my opinion.

Here's another video of the same bush: https://www.youtube.com/watch?v=RQcS5vFBAdg
(I'm the "AI" here. Red arrow means I can see him, green means hidden/safe. The data is drawn from targetKnowledge command, which reflects what the AI would see in my shoes)

The first bush has the same problem.

I tried to keep it as short as possible, that 30 seconds video took me an hour to upload - my internet is pretty terrible.

In any case, I'm glad you made another vid, with your tool it shows the problem perfectly, and it's worse than I thought (I only thought they can see through sides, but it looks like even the middle is problematic).

It should (your vid) hopefully help the devs to acknowledge, and fix the problem quicker.

I think AI can see through every bushes and trees! Not funny on tanoa...

Yep, extremely boring and immersion killing.

dont forget the grass -> https://streamable.com/08b9q

For this reason, Tanoa is a beautiful island on which no one wants to play :)

AI do 'see' through some parts of trees, bushes and grass.

I think the problem is they can identify and accurately target an enemy even if they 'see' a few pixels of a character.

The most annoying thing about ARMA3 for me...

with latest DLC, AI can see through bushes and trees again...

Tanoa is unplayable... again...

Issue persists in 1.84

Just in case devs are not convinced this is an issue, here is an AI shooting through 3 sets of these bushes:
https://www.youtube.com/watch?v=tKJkzXQKXS4

To better understand what happened - after I got shot, the other player hid behind the problematic bushes, AI was behind his set of same bushes 100m away, and in between them was another set of those problematic bushes. AI shot through all three of them until the player went prone, the AI stopped because the grass is now blocking his view.

Here is another situation recorded from fps view:
https://www.youtube.com/watch?v=DQuq7uk93hA

This one is to demonstrate that you definitely can't see them from fps view, while they see you. Accuracy is reduced so I don't get killed first time I peek out.

The number you've dialed is out of service.
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True, I hoped maybe one of the devs spots it on a recent activity tab, but it seems that doesn't work anymore as well (stuck on 27th october).

It's strange that they don't fix this, I once reported the same issue on CUP tracker (AI saw through the tree crown on Chernarus) and it was fixed the very next day. So it can't be that hard to fix.