Is it possible to make location-specific DT or DR in New Vegas? I'm specifically thinking of making it so helmets don't apply any DT to the body and only apply if you hit someone in the head while body DT doesn't affect headshots.

I'm not intimately familiar with the game settings, but it seems like this should be possible.
You'll have to raise the DT on all the helmets though, since they're statted according to their coverage. A proper combat helm is likely thicker and tougher than the armor it matches.

That's the plan, if I can get location-specific DT working at all.

It's a [censored] easier than location-dependent armour was in Oblivion, that's for sure.
You can potentially make all armour just add perks using Modify Defender DT, conditionalised on hit location. The downside to that is compatibility with mod-added content, and it'd prevent NPCs from intelligently selecting armour (as everything would have DT 0, or at least DT Minimum Value One Bit Of The Suit Offers). Plus it won't take armour condition into account.

You could do it on the fly with NVSE, by adding a token to nearby actors to watch their slots for item changes, and if they put on something new get it's DT, modAV their DamageThreshold AV to reduce it by that amount, then add a bunch of 'binary bit' factions to the NPC and a perk that mods DT dependent on the membership of those bits (e.g. it has one perk entry for Increase Defender DT by 1, conditionalised on isinfaction Bit1 == 1, one for Increase by 2 conditionalised on Bit2) to enable you to represent the maximum number of DT values with the minimum number of independent perk ranks.
Downside? Messy, costly and still won't take armour condition into account.

I'd lean towards method 1 and make compatibility patches, because method 2 is going to be really clunky and require you to spend several hours setting up 8-'bit' perks for every hit location.

e: Altered to replace items with factions, as items break AI when added during combat.

Alternatively, you could have the DT be normal but have helmets reduce the defender's torso DT and armor reduce the defender's head DT, assuming Modify Defender DT works with negative values (and I can't see why it shouldn't). Excellent - this should be pretty simple, then, if a bit time consuming.

It doesn't, sadly.

I just tested it. It works perfectly (except there doesn't seem to be a minimum DT - in my test I got a DT of -16.0 once I took my armor off )

Will need to include a minimum in that, then. Still too bad armor condition isn't going to be taken into account, though.

Ah, I thought you wanted it per-limb too (so security guard/combat armour doesn't reduce damage to arms by as much). That makes it a lot less time-consuming.

I thought of that, but the primary thing I really want is so that if I shoot some guy in the head who is wearing power armor but no helmet he'll get splattered, but if I use the same weapon and shoot him in the chest he won't even feel it.

I would cheat it a bit...

- No helmet DT? No DT at all if you get hit in the head.

- Helmet with X DT? Calculate the helmet slot's DT (no matter what they're actually wearing) as total DT/2 or DT/3. So an armored trooper with 30DT total would only have 10 or 15 DT in the head slot.

Which would make heads weaker, without having to fiddle with adjusting helmet DT values.

I'm planning on adjusting all armor DT values (as well as weapon damage values and most ammo modifiers). I'd need to modify all of the helmet/torso armors anyways in order to get this to work, so modifying their DT values as well won't be too much of a problem and won't introduce any new compatibility issues.

Well, except that any added armors that balance themselves around the original DT values - would not be balanced after installing your mod that touches all DT values. Most armor mods tend to base themselves on the original DT/DR values in-game.

(Not saying that you can't do as you please, but since I like to install add-on armors, I would personally not install a mod that doesn't play well with 3rd party armors. Depending, of course, on how much you nudge the DT values around.)

This is true, but this mod wouldn't play too nice with such mods anyways, since you'd have completely different behavior from 3rd party armor as per location-specific DT. For example, if you've got body armor that provides 30 DT and head armor that provides 30 DT and the body armor is third-party and not integrated, you'll wind up with 60 DT when shot in the head. That's no fun.

As for how much the DT values would be nudged, at the moment I'm looking at a bit less than doubling the upper-tier armor DT with smaller increases for the lower-tier armors. This is going to go along with weapon rebalancing so that some weapons will have greater armor penetration, but a lot more won't be able to penetrate upper-tier armor without armor-piercing ammunition - rifles (except the AM rifle) top out around 50 armor penetration prior to armor-piercing ammunition, making armor-piercing ammo much more useful for taking down people in power armor (which also tops out around 50 DT). Energy weapons will probably be rebalanced so that they can actually penetrate armor rather effectively, too, unlike their current super-svckiness. I haven't fully decided on how everything's going to balanced yet, but you should wind up with things with similar ammunition dealing similar damage. A big change is that weapons would have wounding modifiers depending on caliber, so while a 12.7mm pistol round won't penetrate armor as well as a 5.56mm rifle round, it will deal a lot more HP damage if the target is unarmored.

In general, I'm not too worried about maintaining balance with third-party mods - this is going to be a general combat damage system overhaul and those tend not to be too balanced with non-integrated third-party mods. I may include a bare-bones vanilla-DT/no weapon changes version, though it's not what I'm actually planning for at the moment.

Does the game get location specific on hitting? Aside from Head/Body? Seems to me like it should..... are there commands available to determine just WHERE something got hit, and then determine what armor type they are wearing, and determine from there???

Yeah, there are functions to get the hit location (Head, Torso, Right/Left Legs, Right/Left Arms), but you need to use NVSE functions to get what type of armor they're wearing (or a whole lot of conditionals).

Well, I got this almost-working - until I found out that actor effects with hit location conditionals don't actually do anything. It's as if the GetHitLocation function is always returning -1, no matter where you shoot the person - at least, that's how it seems to me during testing. Very annoying.

(Also, I was under the impression that perks could be added to non-Player actors, but that is not, in fact, the case:/)

Hm, well GetHitLocation is a picky function. I think the only confirmed uses have been in critical enchants and various offensive perk entry points, shame it doesn't work for defensive ones. Maybe something for the wiki.

Perks not being added to actors is a weird one- didn't they fix that for NV so they could add the companion suite perk? If they didn't, that kinda svcks.

You can add perks to NPCs, but perk entries only run on the player. (Edit: in FO3, and doubt its changed)

If I do AddPerk *Whatever* and then HasPerk *Whatever*, HasPerk always returns 0, so it doesn't look like you can successfully add perks to NPCs.

EDIT:



I just checked - GetHitLocation isn't used in any offensive perk entry points either (and doesn't work in them as far as I can tell).