Zed sight and hearing...

[entspeak 374]

I know that zed AI is a work in progress, we aren't seeing the zeds that will be in the final game and there are other issues like zombie pathing in buildings that need to be worked out, so this is not a suggestion on how to make the game work now, but an idea for how, possibly, to proceed and provide an interesting dynamic with zed encounters, allow for stealth, and have serious consequences for recklessness - aspects of survival.

 

I originally brought this idea up a while ago with the mod and there were serious limitations with this because of the limitations of the Arma engine to which the mod was bound. Not long before SA was released, however, the devs for the mod made huge leaps in Zed AI that were very similar to these ideas (see Zed behavior in 1.8.1).  My hope is that the Standalone brings more flexibility when it comes to Zed AI.

 

So, this idea hinges upon a fundamental premise (to which there is one exception): Zeds react differently to sound than they do to sight and they don't aggro unless they see a target.  With that in mind, here are ideas for the various ways zeds interact with their environment.

 

Sight:

 

1. Zeds should have fairly poor vision compared to players - maybe 100m with a 40 degree FOV.  Now, these zeds are different from the ones in the mod in that they no longer simply see straight ahead... if they turn their head, they may see you (at least, that's what I've been told, perhaps a dev can confirm this).  So, this that if they look around, they will see more around them.  In reality sight works like a cone: narrower closer to the face, wider as it spreads outward from the face up to the limit of vision.  Most humans have good peripheral vision, so our FoV is roughly 190 degrees (95 degrees to the sides out of each eye).  With a FoV of 40 degrees, however, zeds will basically have tunnel vision.  The conical nature of it however, means you will be spotted if you are 10m off to the right of a zed at a distance, but you will not be seen if you are 10m off to the right of a zed close up.
2. If a player is in the Line of Sight of a zed, the zed should target him... even if the zed was aggro'd by something else.
3. If a zed loses Line of Sight, it will continue to aggro toward the location at which it lost LoS and begin a slow search for a minute.  If it doesn't see a player... any player, it forgets what it was going after and resuming it's unalerted status.
4. At night, the distance a zed can see should be drastically reduced (if possible, based on the amount of light available).  It would be awesome if shining flashlights, flares, fires, etc... would increase the distance a zed could see.

Sound:

 

Going with the premise that zeds only aggro based on what they can see, how they react to sound will add an incredible amount of dynamics to zed interaction and give players lots of ways of dealing with them.

 

1. The exception to the premise: only very loud sounds should immediately aggro zeds.  What the devs in the mod were able to do is to create ranges at which weapons would aggro zeds and ranges at which it would simply get them to walk toward the sound slowly.  I think the SA can build upon this idea. and this can be different for different kinds of weapons.  So, each kind of ammo (since, I understand audible range is based on ammo type and not weapon type) will have three zed related sound distances: the distance at which a zed will definitely aggro, the distance at which it will only become aware and walk slowly toward the sound, and the distance at which it hears nothing.
2. Zeds aggroing based on sound should run toward the sound for a minute (or until they reach the point at which the sound occurred).  If no players come into their Line of Sight during that time, they do the short search and then forget what they were doing and return to their unalerted status.
3. Going with the premise and its exception, the same sort of idea can be applied to other sounds a player makes: footfalls, direct chat and wounded/sick noises.  I think it would be obvious that in order to instantly aggro a zed with footfalls and voice, you'd have to be pretty much right next to it... so, what should happen more often than not is that loud running and talking should, at most, only cause a zed to become interested and walk toward the location it hears the sound... of course following all the rules for sight mentioned above.  Of course, the distance at which zeds are alerted can be based on movement speed and material that's being run over (cement, grass, carpet, wood floor).  What this means is that you can get into trouble pretty quickly if you run right by a zed... running at a distance, may not cause a problem unless you're sprinting on tarmac... and even then, you're going to get a bit of a head start as they slowly turn toward you... and if you duck around a corner, they might not get that chance.
4. Perhaps, at night, as vision is reduced, zed hearing gets slightly better and the distances at which zeds react gets higher.

The limitation on sight and its interaction with sound will make for an incredibly dynamic gameplay experience, I think.

Edited March 24, 2014 by entspeak

[Pvt_Larry (DayZ) 98]

All very good suggestions I think.  It would definitely allow some degree of stealth in the game, which would have some interesting implications.  How would the zombies react to sound made by other zombies though? Simply run to that location, or make it possible to aggro a group of zombies if you're spotted by a single one?

[entspeak 374]

All very good suggestions I think.  It would definitely allow some degree of stealth in the game, which would have some interesting implications.  How would the zombies react to sound made by other zombies though? Simply run to that location, or make it possible to aggro a group of zombies if you're spotted by a single one?

That's an interesting question.  I think zeds should react to other aggroing zeds by slowly turning and walking toward the location that the original zed heard the sound - almost like responding to a call.  This falls in line with the fundamental premise of not having zeds aggro unless they see a player.  Now, if this responding zed sees a player during that time, it should aggro on that player - even if the player isn't near or didn't make the sound that the original zed responded to.  And zombie aggro sound should only be heard or have an effect over a certain distance and would never be loud enough to instantly aggro another zed.

 

This creates another level of dynamic response.  With aggro based on sound, this shouldn't come up, really - it may, but it's unlikely; because if one zed is within aggro range and another is not, but still within range to be affected by a zed noise, it's likely already going to be within the range of the original noise to be turning and walking toward it on it's own and wouldn't be responding to the zed, but, rather to the original noise.

 

Where this will definitely come into play is with aggro based on sight.  If a player aggro's one zombie, other zeds within hearing distance of that zombie's call will slowly turn and walk toward the position the other zed is heading, but only aggro if they see a player - even if that player isn't the one the original zed is targeting. It's like the other zeds in the area go... "hey, this zombie is on to something... it may be food."  So, the fascinating thing is that it could have a domino effect.

Edited March 24, 2014 by entspeak

[ld-airgrafix 403]

Atm superman vision, when they turned they lost their ears

[entspeak 374]

I understand that.  The post is a suggestion for how the zeds may work in future... not a comment on how they work now.

[Ninja_Meh 115]

ENTS MAN long time no see buddy, we should hit up some standalone together mate, maybe we can make some informative videos on how not to suck balls at this game even in its current test phase state XD

 

would be nice to play with someone who recognises that these issues are all KNOWN by the devs and there is a lot of work going on as we type to fix issues all the time. add my steam bro ninja_o_burisuta

 

iv missed our test group skype ramblings man lol :D add me you bumbasquat

[georgiapeach 34]

Hi,

 

nice summary/ideas.

 

Maybe it is enough that Zs move their head (direct the "cone of sight") to the noise if loud enough. So if a Z hears an aggroed brother he looks in the direction of noise for a few seconds.

 

I like the idea that they can alert each other somehow things could get out of hand fast.