Definitive Guide to Fallout Calculations

[johnpaulkenya]

I'm looking for a reference that will show me how each individual skill's success and effect rates are calculated, and how every aspect of combat is calculated as well. I've found some sporadic information here and there, on this forum and elsewhere, but I'm wondering if there's a comprehensive summary I can read. Thank you.

 

[zaopatrzeniowiec]

The best information u can found on wikia. It contains all known math.

 

[johnpaulkenya]

Okay cool.

So i'm looking into the damage part and I find this helpful but confusing algorithm:

ND = net damage value
RD = random damage value produced from weapons hit damage range
RB = ranged bonus (RB=0 unless the player has Bonus Ranged Damage perk)
CM = critical hit damage multiplier (if no critical hit then CM=2, otherwise assigned value from critical hit table)
ADR = armor damage resistance value
ADT = armor damage threshold value
X = ammo dividend
Y = ammo divisor
RM = ammo resistance modifier (only value allowed to be negative or positive in the equation)
CD = combat difficulty multiplier (Easy=75, Normal=100, Hard=125)

Original:
ND = (((RD+RB)*(X*CM)/Y/2*CD/100)-ADT)*((100-(ADR+RM))/100)

Questions (if there's a tut or something that explains all this, I couldn't find any):

Where are the ammo dividend/divisor values drawn from?

Can someone explain the RD value to me like I'm five? The description there is throwing me for a loop.

In fact, if someone wouldn't mind taking the time to detail an example of this algorithm, it would be a huge help.

Thanks.

 

[NovaRain]

Glovz's thread has better explanation.

 

[johnpaulkenya]

Okay that definitely helps, but I'm still lost on some of the values. An example calculation would really help put things into perspective for me.
Also, with respect to the example tables in Glovz's thread, what does the left most column (under adr/adt) represent?

 

[NovaRain]

Also, with respect to the example tables in Glovz's thread, what does the left most column (under adr/adt) represent?

That's the damage done by weapons.

 

[Sduibek]

That takes care of combat damage calculations, what about skills?

 

[johnpaulkenya]

That takes care of combat damage calculations, what about skills?

i too am interested in this

i'm also going to try to put together an ND calculation and see if I've got it right

 

[johnpaulkenya]

followup: this is the ranged damage calculation, is the HtH available as well?

 

[johnpaulkenya]

Okay I've figured out how to apply this formula for all combat but I'm tripped up at two parts: the ammo divisor/dividend, and how to read the "original formula" table on the wiki. (http://falloutmods.wikia.com/wiki/Fallout_engine_calculations#Damage_and_combat_calculations)

I should be good once I understand those two things.

 

[johnpaulkenya]

bump

 

[Glovz]

Okay I've figured out how to apply this formula for all combat but I'm tripped up at two parts: the ammo divisor/dividend, and how to read the "original formula" table on the wiki. (http://falloutmods.wikia.com/wiki/Fallout_engine_calculations#Damage_and_combat_calculations)

I should be good once I understand those two things.

Given there are examples on the wiki so that you can see how the formula works - what exactly are you having issue with?

 

[johnpaulkenya]

well I can't figure out where the divisor/dividend come from, or how they're determined, or what the actual intended effect is from that.

I also can't make sense of the tables, i don't understand how they're labelled.

Original Formula
N LA MA CA PA APA
ADT 0 2 4 5 12 15
ADR 0 25 30 40 40 55
----------------------------------------------
5 8 4 3 2 0 0
6 9 5 4 2 0 0
7 11 6 5 3 1 0
8 12 7 5 4 1 0
9 14 8 6 5 2 1
10 15 9 7 5 3 1
11 17 10 8 6 4 1
12 18 11 9 7 4 2
----------------------------------------------

the ADT and ADR parts I get, but the 5 - 12 rows beneath make no sense to me. I'm sure I'm missing something, hopefully you can point it out for me?

 

[Glovz]

The divisor/dividend or X/Y comes from the ammo as seen on the wiki:
10mm JHP Ammunition
Ammo X/Y 2/1
Ammo RM 25

ADT and ADR come from the armor as seen on the wiki:
N LA MA CA PA APA
ADT 0 2 4 5 12 15
ADR 0 25 30 40 40 55

The possible hit value comes from the weapon:
10mm Pistol has a possible hit between 5-12 before any calculation

The charts on wiki not only show the outcome of applying the formula but the inherent flaw in it when it comes to AP ammo.

My mod/fix which is include as an option in sfall changes that to be what should have been intended without modding weapons, armor, or ammo.

 

[johnpaulkenya]

Ohhhhhhhhhhhhhhkay now this is starting to come together. I didn't realize those were the hit chance, that makes a lot more sense now.

I'm sorry, I must be really thick headed here, I see where the values come from for the examples (the X/Y divisor/dividend) but I don't understand what they represent or how I would derive those values from ammo that ISN'T on the table.

Also, I saw your fix and I'm very interested...now that I know what I'm looking at...

 

[Glovz]

If you look at the ammo proto files using a tool or the mapper, you should be able to find X and Y easy.

How those values were intended to work has always been a little unclear, but they would seem to help differentiate ammo and how much a critical hit has an affect.

As many have found out, the best way to determine what you want is to experiment and see how best to work within the limitations of the engine.

 

[johnpaulkenya]

I'll dig into it. Thank you so much, this was buggin me for weeks.