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Code Vehicle Armor-Penetration and whatnot.

I've been looking at this myself, I'm just wondering about the shatter mechanics:

Code:
// Use the non-weakened PRRatio for shatter calcs, as we don't want more rounds to shatter the more damaged an armor plate gets
if( bMayShatter && NonWeakenedPRRatio > ShellProjectile.ShatterNumber && !ShellProjectile.bProjectileIsHEAT )
{
	bShattered = true;
	FinalPRRatio = PRRatio * ShellProjectile.ShatteredPenEffectiveness;// PR_Final
}

If I'm using the PTRS with these stats:

Code:
Caliber=14.5
ActualRHA=36
TestPlateHardness=300
SlopeEffect=0.47989
ShatterNumber=1.1
ShatterTd=1.0
ShatteredPenEffectiveness=0.3

against the sides of the t-70:
Code:
...,PlateThickness=15,OverallHardness=450,bHighHardness=true)

Td is based on the raw thickness of the armour vs the shell calibre, so it already passes the ShatterTd value and makes the round prone to shattering. The NonWeakenedPRRatio (assuming I shoot it point-blank at 90 degrees) is probably going to be between 2 and 3 (edit: did some quick mental math, it's like 1.67 or something). The shatter calculation then compares this would-be easy penetration to the ShatterNumber, which then qualifies the round for shattering and multiplies its penetration ratio by 0.3. This would then reduce penetration ability to under 0.89 - creating an immediate undermatch.
Obviously this only kicks in if PRRatio is > 1.1, so I can shoot the sides of a panzer or t-34, but there seems to be a point now where I get penalised for taking a safer shot, which would lead to weird penetration arcs with big dead zones in the middle where the extra penetration isn't enough to overcome the shatter penalty... :confused:

And yes, you don't always get the "expected" or "intuitive" result. It is also related to how fast the round is traveling (from memory) - so a "safe" shot can actually be "too good", causing the round to shatter. I'd love to have the time to analyze it all out in all possible variants!
 
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so a "safe" shot can actually be "too good", causing the round to shatter.
YES I KNEW IT. I thought it seemed funny but here is that sweet sweet confirmation.
The PZB seems to have that issue because its base penetration is higher but all of its shatter properties are the same so it will shatter against some plates the PTRS would penetrate.
 
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Yeah if you guys get stuff like that you could tell me the deets and I can try to calculate wassup.
Would help me hammer out this penetration formula.

Well I will have the "Damage Points" Displayed to the HUD in the next release of TE_TankGunnery. I am just not 100% sure what the "Damage Points" mean..:confused:

This will make more sense once you play the map but..
For Example:
PTRS1941 vs PNZ III

32 Meters
Shooting straight on at left side of Tank

Shot -- Damage
1 -- 125
2 -- 825
3 -- 1440
4 -- 1794
5 -- 1080
5 -- 3128
6 -- 2231
7 -- 2436
8 -- 2641 (Kill Shot)


Another Try with same situation

1st Shot Kill with Damage points at 1344.

On the other hand, land an AT Grenade on the rear deck of the tank for a One Shot Kill and the damage is almost always 2020??
 
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W
32 Meters
Shooting straight on at left side of Tank

Shot -- Damage
1 -- 125
2 -- 825
3 -- 1440
4 -- 1794
5 -- 1080
5 -- 3128
6 -- 2231
7 -- 2436
8 -- 2641 (Kill Shot)


Another Try with same situation

1st Shot Kill with Damage points at 1344.

On the other hand, land an AT Grenade on the rear deck of the tank for a One Shot Kill and the damage is almost always 2020??
That's incredibly strange. According to the Sauce Code the tanks only have a few hundred HP, 600 or 800 off the top of my head.
Maybe whatever is telling you that is counting damage done to the whole vehicle as well as component damage and maybe damage to the armor???
I dunno.
All I really know how to figure is how likely a shot is to penetrate.
 
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That's incredibly strange. According to the Sauce Code the tanks only have a few hundred HP, 600 or 800 off the top of my head.
Maybe whatever is telling you that is counting damage done to the whole vehicle as well as component damage and maybe damage to the armor???
I dunno.
All I really know how to figure is how likely a shot is to penetrate.

I have a theory that each section of armor has independent hit points that get drained, but dont neccesarily kill the tanks. This same section of armor can then still be "damaged" although it no longer affects the overall health of the tank. This is all guesswork and I cant really confirm the numbers I am getting back from the Kismet are in line with the code.
 
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Basically, what Mets is saying. Fire up the gunnery range, grab both rifles and lay down 10m from the side of a tank. The enemy rifle will kill it in one shot, or at least penetrate it every time, the friendly rifle will shatter. AFAIK, the rounds are the same and the rifles nearly so.
 
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I have a theory that each section of armor has independent hit points that get drained, but dont neccesarily kill the tanks. This same section of armor can then still be "damaged" although it no longer affects the overall health of the tank. This is all guesswork and I cant really confirm the numbers I am getting back from the Kismet are in line with the code.
From what I understand, each plate does have a 'strength'. Repeated hits weaken the plates, so I suppose that counts like HP.
Basically, what Mets is saying. Fire up the gunnery range, grab both rifles and lay down 10m from the side of a tank. The enemy rifle will kill it in one shot, or at least penetrate it every time, the friendly rifle will shatter. AFAIK, the rounds are the same and the rifles nearly so.
I think the idea is that the Pzb uses the tungsten carbide cored rounds. They are identical except for a higher actual RHA penetration. If I were the one doing the coding, I would've made the penetration be the same but given the pzb a higher ShatterT/D and ShatterPen/Res.
 
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I thought the Pzb lost the tungsten rounds a while ago? Allied AT heroes were using the PZB to devastating effect against PzIV's.

[url]http://forums.tripwireinteractive.com/showpost.php?p=1354140&postcount=54[/URL]
That refers to the level 26+ Pzb.
That's odd I didn't know there was a difference between 0-25 and 26-49. Very wonk indeed. The Sauce says it has an actual RHA penetration of 45mm of 450 BHN steel. Which is definitely better than what the PTRS does.
Then again,
could my Saucecode be outdated?:confused:
 
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Another odd situation regarding these damage points:

Shoot T34 with PZB between the front two road wheels straight on from maybe 15 meters, no kill but damage of 1300.

Now I switch to P38, which normally does no damage to a tank.

I shoot the same spot that I did with the PZB, It registers 50 points.

Each additional shot goes down 1...49, 48, 47, 46

After numerous reloads, I get it down to 1. Then I am unable to further damage the tank with the P38. Tank is not dead yet either... just odd.
 
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Another odd situation regarding these damage points:

Shoot T34 with PZB between the front two road wheels straight on from maybe 15 meters, no kill but damage of 1300.

Now I switch to P38, which normally does no damage to a tank.

I shoot the same spot that I did with the PZB, It registers 50 points.

Each additional shot goes down 1...49, 48, 47, 46

After numerous reloads, I get it down to 1. Then I am unable to further damage the tank with the P38. Tank is not dead yet either... just odd.
Yeah I mean,
just
I have absolutely no idea.
I'm level 45 with the Pzb and 50 with the PTRS, there's zero apparent change in either AT rifle as you level up. I paid attention...... ;)
Yeah that's what I thought.
That is strange :/
 
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DOSH said:
And yes, you don't always get the "expected" or "intuitive" result. It is also related to how fast the round is traveling (from memory) - so a "safe" shot can actually be "too good", causing the round to shatter. I'd love to have the time to analyze it all out in all possible variants!

thanks for replying, even if I didn't check it for months afterward :D

I even ended up digging up my walkthrough on the code, and finished off the last few lines :eek:

*will post link, pm me if I forget for some reason*
 
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Okay so I derived some formula type dealies
Spoiler!

It's been awhile since I made it so I don't quite remember how I got all of it. Could be out-dated too.

I know from penetration down is my weird way of doing the bell curve. I know there's a better way to do it but don't feel like bothering right now :p
 
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Ooooooh ok most of this is in ROAntiVehicleProjectile.uc
that was probably obvious to people other than me but that's what happens when I don't know the first thing about unrealscript. . .or whatever this is exactly.
Not exactly actually all of the penetration calculations are done in ROTreaded.uc
 
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