Sandbag walls

[Balschoiw 0]

Situation:

I got a line of sandbag walls. Behind the sandbags are units on the ground via this setunitpos "DOWN" as they wait for armor to run into a minefield straight in front of them. I also disabled "ai move" as I want to have them grouped but not moving. They can turn on the spot, so it should be ok.

Once the armor runs into the minefield, I tell them via trigger to setunitpos "MIDDLE", combatmode "RED" to engage remaining tanks and infantry but they don´t do the job right. They fire from time to time but mostly get mowed down by infantry from far away without reacting to the incoming fire appropriately.

As I thought the sandbags may be too high, I setpos´ed them 0.2 below ground but basically not much changed.

What is wrong ? Even enemies on the other side of the bags, like 5 meters away sometimes just stare into the direction of the unit behind the sandbags but do not fire.

What is wrong with those sandbag walls ?

Another question:

Don´t the mines have any explosion sound with 1.08 anymore ?

I hear no explosion, but only the tanks explosions. The mines blast silently

[somethingcool 0]

I have expereinced the same things as you mate, and ended up just giving up, seems to be an engine limitation or something stupid!

If you let them move they move outside of the safe area behind the sandbags but suddenly are able to fire effectively, seems ArmA's AI like to take a different approach responding to effective enemy fire ey;)

If you find a way around let me know!

[Doolittle 0]

Unfortunately, there's a bug where AI won't shoot over objects.. http://bugs.armed-assault.net/view.php?id=1634

[Törni 0]

Great. This also explains why AI rarely uses any cover at all. Even in urban areas they like to stay in the open.

A hull down position for an AI tank. Must be dreaming...

[Balschoiw 0]

Quote[/b] ]Unfortunately, there's a bug where AI won't shoot over objects..

Well...they sometimes do shoot , but most of the time they don´t.

I will do some tests on flat ground to make it reproduceable and play around with the setpos.

For me it seems like it´s an invisible box or something that hinders AI to shoot. A stationary mg positioned behind the walls in a bunk (no need to say that I had to setpos the MG +0.2 m aswell as AI refuses to fire when MG is on default ground position) shoots over the sandbags. Even RPG is fired from behind the sandbags if they are lowered a bit into the ground, but regular gunfire seems to be a problem.

What makes me think of that "invisible box" even more is that grenadiers with their high aiming do shoot perfectly behind sandbags.

I guess it´s an error in the sandbag-wall object for some reason.

I will test tomorrow.

[Donnervogel 0]

It's the OFP derived AI. Objects are obstacles for it. If the AI is close to an Object it "feels" obstructed. it has been like that since OFP. I don't know the exact problem but I suspect it's some general flaw in the engine that AI is unable to "interact" with objects. You can see ti with shooting but also with movement (good example is the FDF AP mines which the AI avoided since it "saw" an object in it's way so it went around it

And about the cover. The AI goes to cover (or better it will stand around close to something it thinks is cover so the thing is between him and the unit it wants cover from - you can tell it to do so by scripting for testing) but it usually won't fire from there because of this reason discussed here. So it will step out of cover again in order to engage.

Arma (OFP derived) AI is not able to interact with objects is what I think and I think it won't be really changed anytime soon. But hopefully they will at least enable it to fire over objects.

We need a major engine expansion or Game2 to see proper interaction with objects I think

[madrussian 347]

This problem in OFP had a workaround.

If you simply do a "setdammage 1" on the object in question, the ai will then fire freely over the object in a normal manner (at least w/ guns, not as sure about rpgs).  The nice thing is, with objects like sandbags, they don't look too much different once they get "destroyed".  

Now, sometimes in addition to the "setdammage 1", you had to sink the object slightly using setpos to get the ai to shoot over the objects.

Not sure how this trick will work in ArmA though, but in any event good luck...

[somethingcool 0]

In ArmA the objects mystically dissapear 0.0

[Second 0]

Look at here LOS Subject

And look at parts where boundingbox is mentioned. (Look at Blanco's reply. I think it was 2nd in order.

Pretty many objects are consideret to be much bigger by AI than they actually are to us.

I tried to use graves ( HEY! I might be graverobber, but their color fits to most terrain! ) as foxhole's fragmentwalls, but it was disaster because of the same thing. i even left 1 meter of free space to spot where they are expeted to shoot, but no luck. Attacker noticed defender from about 30-40 meters. But defender didn't see attacker until it was in distance of 3-5 meters from him, and shooting at him.

That what dear member Donnervogel said seems to be true. Closer AI is from some (bad-)object more blind it gets. Doesn't apply to all objects (like actual fortification-objects), but in overall damn too many. This might cause whole urbanwarfare blindness issue.

[Blanco 0]

I don't think LOS is restricted by boundingboxes, if that was the case AI would never fire when there street between the attacker and defencer because boundingbox values for streets are 3 meters high.

View LOD of the sandbags are good, because knowsabout is between 1-4 and they track the enemy. I think the fire LOD are the problem here.

Here's another topic about this subject on OFPEC.

http://www.ofpec.com/index.p....29625.0

[Balschoiw 0]

Damn

This doesn´t look like a thing that can be fixed by us.

Grrr....

[Big Dawg KS 6]

Great. This also explains why AI rarely uses any cover at all. Even in urban areas they like to stay in the open.

A hull down position for an AI tank. Must be dreaming...

That's totally unrelated.

[nettrucker 142]

Try using the " this setDamage 1" in the sandbags initfield command. That was the work around in OFP if I'm not wrong.

[Big Dawg KS 6]

That won't work with the ArmA sandbags because they disappear when destroyed.

[Blanco 0]

Is there something in the config that makes it disappear?

[Second 0]

I would guess that it is 'destrtype' (which is refering to type of destruction). 'Fencewood' object doesn't have anything specified, so i quess it has same 'destrtype' as with buildings.

Intresting thing is that i tried to create fencewood2-addon that was identical to fencewood-object and added 'destrtype = destructiontree' (should fall to it side, i quess). Addon didn't work, no errors displayed but game just didn't just create object... and this happened only after i added that destrtype to it (worked well before that). I was lazy and didn't add it to object menu so i needed to use createvehicle. But i am addon-newbie so it might be just me.

Ps. Am i hearing strange voices, but when hitting sandbag-walls with bullets i get sound of bullet hitting metal... or did i just mix something?

Pss. Oh and they just don't disapear (atleast in my ArmA): They blow up (flash and crumbling), like building... Units near by might get killed because of it. Is this correct (don't know if some addon mess it)?

[nettrucker 142]

Hi everybody

Use - this setDamage 0.95 - in the sandbags initfield. So it won't disappear and Soldiers in position behind the bag will fire over them. I tested it and it works.

Cheers

nettrucker

[johnnyboy 3797]

Quote[/b] ]Use - this setDamage 0.95 - in the sandbags initfield. So it won't disappear and Soldiers in position behind the bag will fire over them.

I tried this, and it only works for me if the shooter is standing (which worked without setting damage). In crouched mode, he still won't fire over the sandbag. And now the sandbag explodes and kills him if the sandbag takes 10 or 20 bullets (i.e., another .5 of dammage). This might be able to be overcome if we put a HIT eventhandler on the sandbag object to keep resetting damage to .95. But its not worth it to me if the AI won't shoot over them while crouched.

[nettrucker 142]

Hello JohnnyBoy

I've tried it yesterday. I put 2 machine gunners behind the sandbags in crouched position in their init fiels I wrote " this setunitPos "MIDDLE" set skill level to max. and they fired, not over long distance but they fired. Well

I dunno if this will ever going to be fixed by BIS. I can't tell you another way to make them shoot over the sandbags.

Cheers

nettrucker

[tekpc007 1]

WOW i just spent an hour making a mission with this addon BOR2 base

made a large force attack this base and no AI in the base would shoot. quite sad...its real game breaker for making battles with large forces and somewhat real base setups.It makes me want to not make any missions .its seems like a real gamebreaker to me. i will vote for this bug but wow only 2 votes?  set damage to is no real solution ;( just my opinion.

[Balschoiw 0]

I agree that this is a very annoying bug and even more annoying is the fact that the old workaround from OFP does not work anymore.

I guess it´s worth a PM to Suma. Need to remind him of embedding a scripting command to silence AI voicecoms anyway.

[Balschoiw 0]

After PM´ing Suma I got his attention to the bugtracker issue

and now uploaded a modified version of Ducus-Sumus mission from OFPEC to demonstrate the bug perfectly.

I´m pressing my thumbs that we will see a solution to this bug that renders AI useless when being placed behind objects.

Edit : Bug assigned by Suma

[Balschoiw 0]

Suma added note on what causes the issues with empty objects and AI, how to fix it for custom addons and indicated that there maybe will be a BIS fix for the issue.

Quote[/b] ]The bug is caused by the function responsible for friendly fire avoidance. Sandbags are considered civilian entities, and therefore friendly, and AI therefore hesitates to fire close to them unless the enemy is very near.

Until we provide a fix, a workaround for addon or mod makers might be to create an addon with alternative sandbags represented with a simulation "camera" instead of usual "house", and use such sandbags in the mission instead of the default ones. Such workaround would have some limitations (sandbags not destructible and not targetable by AI), but it still might be useful.

Another workaround might be to create them with a simulation house, but non-destructible (DestructNo), and then use setDamage 1 on them.

[Balschoiw 0]

Raedor provided us an interim solution for the bug.

Simply unpack the file RAE_sandbafFix.pbo to your Arma addon folder and AI will engage targets behind and infront of sandbags without any problems.

You don´t have to alter your already created missions in any way.

Just tested it and it works great. Still, it can only be an interim solution as we have to pack the pbo-file with our missions.

Download the pbo on the BTS page:

BTS sandbag bug page

Thx Raedor !

[somethingcool 0]

Nice one! Now we have to hope BIS implement a fix in a patch