Advanced car damage: Body damage Instakills the engine (and sometimes turrets)

[Soultechnology]

Mods
Following is what was laoded during testing before this post. This has occured for over a year not, on different muliplayer servers with different mods.

• Arma 3: 2.16 (profiling)
• CBA_A3 v3.17.1.240424
• ACE3: 3.17.1

Description
With Advanced car damage enabled. Damage to the vehicle body can cause the egnine to suddenly take FULL damage. Sometimes also does the same to turret(s) on the vehicle. Some hits to the engine itself also seems to fully detsroy the engine. In vanilla It occurs with the APEX Dagors, and the KARTS gokart.
With mods its common with many light vehicles across many mods tested. First noticed with the RHS uparmored humvees not being so 'uparmored'.

Steps to reproduce:
Place a dagor or gokart, shoot the body, avoid the engine. (amount of rounds to trigger bug may vary)

Expected behavior:
I expect only the body to be damaged, and not the engine effectivly imploding due to cosmetic bodypanel damage from a handfull of rounds. Dont know why turrets are made of glass either.

Where did the issue occur?

• Dedicated / Self-Hosted Multiplayer / Singleplayer / Editor (Singleplayer) / Editor (Multiplayer) / Virtual Arsenal
  (all of the above)

Log Files:
https://pastebin.com/3PR5B8vk

Additional context:
Helped (me) narrow down the issue by using the following code on the target vehicle. Id see the body take damage and it seemed 50/50, when the body took dmaage the engine also took damage. Apon checking it was always FULL damage to the engine. Hits to the engine sometimes also fed back 2 hits to the engine, assuming the second one was what instakilled it.

this addEventHandler ["Dammaged", {
_damagedPart = _this select 4;
systemChat _damagedPart;
}];

This seems small with only effecting these 2 vics, but once othe rmods are involved(cup, rhs, ffaa, anything that adds light vics as far as ive noticed its like half the cars added) Its pretty common and missionbreaking.

Screenshots:
https://youtu.be/cSOz39w_fWM

[johnb432]

Its pretty common and missionbreaking.

Turn it off if it's such a problem - Advanced Car Damage is experimental after all.

[Soultechnology]

Its pretty common and missionbreaking.

Turn it off if it's such a problem - Advanced Car Damage is experimental after all.

Imean, thats the point of making a issue/bug report is it not?
The bit you quoted was just my take on commonality and severity, 2 things you usually wanna include in a bug report.

[Soultechnology]

Doing more and more testing. (on 3.18.0 this time)
While some (car) vehicles have an apperent issue with single rounds killing them. This seems to be a persiting issue to varying degrees with ALL light vehicles. Almost always effects the enigne, but sometimes the turret or gun, and in a few cases the fuel tank.

[Soultechnology]

Welp, kind narrowed it down.
Gonna make a ghetto patch for my unit, but its basically the case"hull" in the finishing switch statement in fnc_processHit.sqf.
Just instakilling bits that arnt hit depending on incoming damage VS vehicle. Was jsut only SUPER noticable on light vics where a 9mm to the door or wing mirror would remove the engine from the vehicle.

[johnb432]

If you manage to come up with a robust patch, I'd be interested in seeing it if you don't mind.

[Soultechnology]

Update:
So, getting bored loking at this so for my group (atleast for now) my fix is gonna be fixing the symptoms not the cause.
bascially, editing the 'hull' case in processHit.sqf As this is causing the damage to other aprts from random hits, but not neecsarily the root casue.

the real cause seems to be body hits counting as structure/hull hits on cars. But this case assume a structure/hull hit is an internal part, and not a flimsy car body.
and on sog cars wheel hits also hit the fuel tank?... im still looking into that one.

May have to make other tweaks to get my fix to play nice and behave as expected. Maybe when i got it ironed out and in use for a bit ill make a pull request if this isnt any closer to getting fixed properly.