Enables AI stalkers to hear and react to nearby bullet ricochet.
Now when you fire and hit something nearby a stalker, they'll react the same way as if they'd heard a nearby gunshot: Get into cover and enter a short alert state, before resuming normal behavior if they don't see or hear any more threats.
The distance of which NPCs can hear ricochets are, as an assumption, 7-20 meters depending on the material that's hit. Metal and glass is the loudest, while dirt is one of the quietest. There is a guide on how to change this down below, as that is handled outside of this mod.
Art by Design1: stalker-game.com
Warnings/Untested Features:
- Stealth untested.
If you notice that Stalkers know where you are immediately after firing, without visually identifying you, please inform me and I'll do further testing. May be unbalanced for stealth.
- If firing a silenced weapon and hitting, or missing, causes alerts please inform me. I may add an optional file to change that, if possible.
- "Impact Sounds v2" may cause stalkers to notice the ricochets from farther away. This should be okay however, as that mod is meant to make them louder anyway. I can change that and release my own version that keeps the noise the same but returns the detection range to vanilla, but you have to ask nicely.
- As of yet, I don't know how to, or even know if, stalkers can hear bullets whizzing by. As of now they won't be able to, only bullet impacts
Anything with a strikehtrough means I have since tested and either fixed, or confirmed it doesn't happen.
Q&A:
Does it work?
Yes! The ability for Stalkers to hear the ricochet from ranges beyond their ability to hear the gun being fired has been has been confirmed, and is also somewhat affected by rain.
Is it compatible with my sound mod?
YES. I said earlier that it is compatible with any sound mod that managed their .ogg files' sound parameters correctly. It also doesn't affect how stalkers perceive things, or how aware they are, outside of the one main change.
Otherwise, for any other mod, as long as your mod doesn't touch "xr_danger.ltx", it should be good.
Where's the usual write up on how the mod works?
Coming after a good night's rest. As always I will add this to the mod page, as the only thing better than making a S.T.A.L.E.R. mod is making a S.T.A.L.K.E.R. modder. It's now here!
Why does the mod come with a file with mad ramblings?
Because I needed to keep notes, and I'll replace it soon with actual notes on how the mod works and how things can be changed for preference. I'll later use that to remember and detail the process for how I made and reverse engineered Dead Air's AI to figure out what I needed to change, to educate modders.
Can I tweak detection ranges?
I won't, but you can. A guide on how to tweak detection ranges is located at the bottom of this mod's description.
How The Mod Works:
This might come as a surprise, but the AI in Dead Air were never deaf to the sounds of bullets striking near them to begin with. They could hear them just fine, but their reaction wasn't strong enough. To make them react to ricochets, I extracted and the edited "xr_danger.ltx", in:
- "\gamedata\configs\ai_tweaks\xr_danger.ltx"
I then changed the "bullet_ricochet" variable from its vanilla values (Note that the contents of the file is not shown in full);
[danger_inertion] ;May use condlists from xr_condition
grenade = 6000
entity_corpse = 60000
entity_attacked = 30000
attacked = 120000
bullet_ricochet = 5000
enemy_sound = 45000
attack_sound = 45000
entity_death = 30000
hit = 126000
sound = 25000
visual = 45000
[danger_object] ;Ignore distances squared -- May use condlists from xr_condition
attacked = 90000
bullet_ricochet = 16
[danger_inertion_actor] ;May use condlists from xr_condition
attacked = 120000
bullet_ricochet = 5000
[danger_object_actor] ;Ignore distances squared -- May use condlists from xr_condition
attacked = 0
bullet_ricochet = {=actor_enemy} 16, 0
to:
[danger_inertion] ;May use condlists from xr_condition
grenade = 6000
entity_corpse = 60000
entity_attacked = 30000
attacked = 120000
bullet_ricochet = 120000
enemy_sound = 45000
attack_sound = 45000
entity_death = 30000
hit = 126000
sound = 25000
visual = 45000
[danger_object] ;Ignore distances squared -- May use condlists from xr_condition
attacked = 90000
bullet_ricochet = 120000
[danger_inertion_actor] ;May use condlists from xr_condition
attacked = 120000
bullet_ricochet = 120000
[danger_object_actor] ;Ignore distances squared -- May use condlists from xr_condition
attacked = 0
bullet_ricochet = {=actor_enemy} 120000, 120000
(120,000 each, because it is similar to being attacked directly in [danger_inertion]) Now the AI does react to ricochet. I'm unsure which of those specifically did the job, but it works, so I don't know if it needs to be messed with right now.
What these other parameters do, I'm not too sure. I also don't know why they're split into groups like they are, and how each one is different. Further testing and modding into these values could make some very good and interesting changes, but that will either be another mod, or a big update to this one if I find anything out.
Tweaking Detection Ranges
Not for the small of patience.
- Get your sound mod of choice or unpack Dead Air's sounds with the Dead Air .dbl Extractor Tool.
- Download and install SAVandT (S.T.A.L.K.E.R. Sound Attribute Viewer and Tweaker).
- Either drag your entire sound mod or Dead Air sound library into the file where you installed SAVandT, but for this purpose you just need the "collide" folder, which is located in "gamedata\sounds\material\bullet\collide"
- Open SAVandT and navigate your way to your "collide" folder, and the files within.
- Tweak the value for "Maximum AI Distance" for each .ogg file to whatever value you prefer. Do it one at a time, or if you don't mind ever sound in the game having similar settings, copy one you prefer and paste it across all of them.If you want as well, you can use SAVandT to tweak what type of sound the game registers it as, how loud it is, and how far/near away you can hear it from. SAVandT is a great tool, but highly tedious when editing files in bulk or when dealing with its file explorer.
Tip: I would recommend having Dead Air vanilla's version of these sound files handy as well, just so you can compare AI distances with something reasonable. SAVandT can have multiple instances working of itself working at the same time by launching the app multiple times, but copying and pasting between instances is not possible; Good for comparing parameters but not much else.
- Paste this all into your gamedata folder, or into whatever mod manager you carry.
Thank you sir! I had noticed too that NPCs are not reacting to ricochets. Without having tested this too much I already like it. :D
Not a sir, but the thanks is still well received.
The reason stealth works is because of NPC's being deaf/blind.
If that's the case, no need to download the mod. I also included a guide on how to lower the range of NPCs' hearing for ricochet, so you can keep them somewhat deaf... But the process is tedious.
I would totally second the notion of NPCs being deaf. Many times I would shoot (missed) directly next to them and they would not react at all even though I was only a couple of meters away from them. To clarify they werent reacting to the gunshot-sound nor the ricochets of the ground. So it very much feels like the AI does not react to player footsteps and/or moving in and out of bushes. Also sound detection on stalkers for mutants seems to be non-existant too.
I'm half tempted to throw in a "max_hear_dist" parameter into the m_stalker.ltx and see whether that nets any result since the described parameter is defined in some other mutant config files but not in the stalker configuration file. Yet I don't know if the stalker sound perception is governed by any other file but the m_stalker.ltx.
You may actually want to check out the file that I modified for this addon, and the section where I describe how this mod works. It actually isn't that stalkers can't hear some things, but that their reaction to it was neutered(edit) changing the values around may fix that in some cases, but I don't know. I'll take a dig in... But I can't promise a mod; not even a good chance of one.
Edit: The sounds that monsters make average 30 meters, or 30 whatever the .ogg files measure. That's about 3 times the distance of the bullet ricochets, which means that stalkers should be able to hear it... But having them react is a different thing.
There's also the [stalker_sound_perceive] section in m_stalker.ltx that might do something.
Had a look at the xr_danger.ltx and it does indeed seem like quite a bit of sound perception is managed there. So far I've managed to make hostile NPCs react to my footsteps and reloading/weapon changing sounds. I'm still not sure though whether I'm changing soundlevels or rather detection ranges in the xr_danger.ltx.
As for the [stalker_sound_perceive] I had already altered the parameters there before but with seemingly no impact on gameplay. So I'm inclined to think that the [stalker_sound_perceive] section is more of a fine-tuning for stalkers sound-perception (It might not be used at all).
Currently I'm trying to find a sweetspot for the detection of dropping bodies but it's hard since proper test environments are rare in the game itself.
Edit: I noticed that the value for "attack" in the [danger_object_actor] section is set to "0". I know it's a vanilla DA setting but can that be right? Whereismy's rebalance has that value normalized with the other "attack" values at 150000. I put mine on DA vanilla 120000 instead of 0 and have not encountered problems yet.
Detection ranges aren't actually handled by ltx files. Rather, the .ogg sound files actually have a tweakable value called "Maximum AI Distance". Changing that with SAVandT (Linked in mod description) changes from how far away NPCs can hear a sound.
I'm not too sure what xr_danger actually does. I have a guess, where it simply assigns a "panic" value to stalkers, and when that value is high enough it triggers them to enter an alert. I think it's a flat panic addition as well, so no drop-off with sound- Rather, if they here it, the value you write(12,000 for instance)is the one they always get.
Also, here's the xr_danger.ltx file used in the Realistic Rebalance mod in Anomaly, if you want to check Dead Air against something closer to vanilla stalker: Pastebin.com
I'm pretty sure the source code/game files for CoP are out in a git library somewhere as well, so you don't have to download and extract everything.
I had feared the audibility was governed by the *.ogg files and I'm just too lazy to change those, seeing I would have to scrounge through oodles and oodles of sounds and assign new values.
Do you know whether the soundrange is capped at a certain distance for NPCs at all?
I'm currently tweaking the m_stalkr.ltx and xr_danger.ltx to get a more stealthy gameplay.
As I mentioned before I can successfully sneak up on a single guy and knife kill him before he turns. I also successfully snuck into Cordon military checkpoint and got the RPG-7.
Currently tweaking to get the gunsound recognition right paired with them not instantly going into alert once one NPC of the group dies.
Results are inconsistent so far to say the least but that might well be attributed to the fact that I'm using the "Impact Sounds v2" mod. So sometimes NPCs are not turning when I think they should. Which would make me think I need to increase the "attack_sound" parameter yet I fear when I amp it too high silencers will become virtually useless. *Decisions, decisions...*
I already am referencing with xr_danger.ltx from the Anomaly rebalance, thanks for the link though. :D
Also: Great tutorial on how to mod the sounds. Kudos to you.
I'm unsure if there's a limit to the soundrange. Alife in Dead Air doesn't seem to spawn past 250 meters from the player anyway, so that's an effective cap.
Apologies in advanced for how long this is with as little info as it gives, exhausted from other stuff.
I think what might be an effective balancing of the silence thing is to give a higher range for NPCs hearing gun shots in general, keeping or lowering their ability to hear silenced gun shots. Currently for most guns the NPCs can hear and react to from 75 meters away. That's for all guns excluding silenced guns. The player can hear gunshots from at least 150 meters away, but up to 300 meters away. I can edit the soundfiles, since I've gotten used to the tedium, and make the NPCs react to all unsilenced gunfire from 150 meters away, and maybe some special cases for the louder and more terrifying guns (RPG, Gauss Rifle etc.).
The activation switch from offline to online A-life is indeed set at 250m.
I'm still fiddling with the AI reaction timings trying to give them a reasonable detection, starting at around 150m actually.
Edit: Don't worry, my posts are rather lenghthy too. ;)
I added a max_hear_dist to the m_stalker.ltx and the game is still starting so I'm guessing there is no harm in doing that.
Currently I have max_hear_dist set to 250m but more testing is needed since the AI seems to react to odd things since I put in the parameter, like aggroing onto anomalies.
Do you know offhand which is the loudest gun? Would help alot for testing purposes, right now I'm using the L96A1, seems to be rather noisy. :D
The TOZ 34 has a Maximum AI Distance of 620, while having a Maximum (player) Distance of 900. I'm pretty sure the AI don't actually hear the TOZ from that far away though, so more might be at play or I'm wrong about something.
Looking through the weapon configs and weapon sounds, things got a bit more interesting. Relevant file is weapons_sounds.ltx if you're curious. Some weapons have their own folder for their sounds, while others are just in the default weapon sounds folder. What's interesting is that weapons that have their own folder have much longer detection ranges than those that don't. E.g, The AK12 has similar statistics to teh TOZ and is very loud, but the Ak74u shot sound effect has a maximum AI distance of only 75 and a player range of 300.
This will also force me to correct what I said earlier: Looking through the weapons_sounds.ltx files it seems that non of the weapon shots outside of their own files are even used, and that's what I used to feed you data about Max AI distance being 75, and player distance being from 150-300. I'll take a closer look this time, and I've also got some tea in me.
Edit: Only *one* shot sound outside of its own file is used by any weapon, and it's "n_toz34_shot". It is *not* used in the TOZ34, instead in the... RG6 Grenade launcher? I don't know why it's used there, but it's being used as "snd_shoot_duplet", which is something I know little to nothing about. It might be a dummy.
Edit 2: Found another one. The AK74u uses a shot sound file outside of its own folder. It turns out that some weapons, in their own .ltx files, have set their own sound settings without reliance on weapons_sounds.ltx.
Also, about them reacting to anomalies: When an anomaly triggers it seems to have a range of 100-300 meters, but their registered as "undefined". Some SFX on anomalies are registered as NPC_Attacking, though not the one's I'd think.
Hmm, the anomalies having NPC_attacking parameters would explain quite a bit. Is it by any chance the whirlig or springboard anomalies which have that parameter defined in their files?
Hitting a little bit of a stump while tweaking the AI detection. (Not having an AI-perception meter doesn't make things easier.)
It seems some indoor areas are plainly pitchblack no matter how low or high I set the luminocity_factor in the m_stalker.ltx enemies cannot find me in those places except for when I engage them first (gunsounds), start running (footsteps+velocity) or use my flashlight (light emitter). The enemies do hear me alright I can see them tracking my footsteps when I'm walking slowly. And it has to be the luminocity in some way since once I shine my headlight they immediately attack me when they were searching before.
Also collision detection seems to be off: My monolith test subjects are bumping into me quite frequently and they do not realize I'm an enemy as long as I don't get lit up by any lightsource.
Long range detection speed is another issue, I'm trying to balance out the detection rate to the fall off when actor leaves visibility (hides in bush) but it's tedious and again proper testing environment is lacking. So any mutant that sneaks up to me usually triggers the AI before I do it myself hence ruining my stealth approach.
Also: the [stalker_sound_perceive] section is indeed used. Setting all factor to 0.0 made the AI oblivious to any player or gunsound. As for the other 3 parameters that are defined there I don't really know how or what they would factor in. Setting the anomaly parameter to 0.0 still has the enemy targetting anomalies. The parameter for item could be items dropping on ground or items being used by actor (NVG, drugs), more testing is needed there. The world parameter though is giving me a blank. I don't really know which sound-volume perception is governed by that. It could be sounds like rain yet the effect would be quite subtle and might be intended as an occlusion value but that's guesswork on my part here.
As for the stalkers not noticing you when you're close, there is a "always_visible_distance" in m_stalker.ltx, which does what you think it does. When stalkers are at rest its set to 0, but in their alert state it should be set to 5 meters.
As for everything else I'm at a bit of a loss myself. Right now, instead of Dead Air I'm working on a (bad) translation for the A.R.E.A. mod. I'll still answer any questions and try to help in what ways I can, but not today as I was on a boat and the world is still spinning for me.
Hmm, boat. :D
Still fiddling with the values though I made some progress in balancing Ai detection speed and radius. The "always_visible_distance" is a tricky thing to use since it literally does what it says, the actor will be immediately spotted if LOS is established even for the slightest.
Oh my translation... well good luck with that. :D
So much good info in this comment section, thank you both for your time making awesome addons!
this is one of the most glaring AI flaws i've found in Stalker, espicially when sniping at range and the bots just casually strolling around until you finally hit them no matter how many near misses you have. Good stuff
It's not so much an issue with stalker as it is an issue with call of Chernobyl (which dead air is based off of)
Quite frankly I'm surprised this mod wasn't made earlier. I had fixed it personally but never had the good sense to release. it's such a simple fix too.
Considering Call of Chernobyl had a prominent AI specialized developer I am still at a loss for how he left this disabled.
I think they werent finished with AI. The m_stalker.ltx has some many placeholder values and many spots where it seems that decimals have been forgotten. Balancing AI is tedious and I'd wager a guess here that the DA devs tuned AI after they had removed the HUD elements i.e. sound and visibilty meter just to make it harder on themselves.
One little example is the fog_density value vanilla DA AI has that set to 12, original CoP setting is around 0.1 I think. A factor 12 basically means that Freedom is having a smokebox within every NPCs gasmask. I would think they meant to set the value to 1.2 which in tests has shown viable. I wonder if one could get the promised DA AI by trying to fix the decimal value errors.
Edit: Just tried the standard DA AI with only the fog_factor set to 1.2 instead of 12 and NPCs are reacting way earlier to actor-model than before.
Only did a small test but I remember you could walk up to the military checkpoint in cordon without too much of a hassle in vanilla DA. Stealth with only that alteration wouldn't quite work tho since a FOV of 110 degrees is short to one third of full radius and well good luck sneaking around that with a perception interval of 0.001 s. ;D
Thanks for your job. Could work on Call of Chernobyl?
There is no reason it shouldn't. I suspect Call of Chernobyl uses different values for its xr_danger.ltx file. This means the AI might act differently if you install my mod as-is, and it could break the game's difficulty. If you only copy and paste the values that I included in the "How The Mod Works" portion of the the mod description, onto CoC's xr_danger.ltx file, you should be able to add only the intended effects.