how does armor mitigate damage? (specifically shields..test included)

[Penitent]

Trying to figure out how sturdy different shields are in relation to hps vs armor values.

How does armor mitigate damage?
For example a shield has 300 hp and 15 armor.  It's is getting struck with blows that do 30 points of raw damage each.  How many strikes before it breaks?

[Cyclopsided]

Trying to figure out how sturdy different shields are in relation to hps vs armor values.

How does armor mitigate damage?
For example a shield has 300 hp and 15 armor.  It's is getting struck with blows that do 30 points of raw damage each.  How many strikes before it breaks?

armor subtracts how much damage is done.
HP is how much damage it will take before breaking.
if armor is high enough it will completely negate damage done to the shield's HP.
Bonus to shields is a modifier that doubles the raw damage of the weapon vs shields.

[Penitent]

armor subtracts how much damage is done.
HP is how much damage it will take before breaking.
if armor is high enough it will completely negate damage done to the shield's HP.
Bonus to shields is a modifier that doubles the raw damage of the weapon vs shields.

Thats how I thought it worked.  I'm running a simple test.

[Penitent]

Actually, it's not quite working out the way you proposed.  It's half true.

I tested several shields.  The person hitting them used a wakizashi, had 4 PS, 73 wpf.  I had 5 shield skill.

According to the "damage-armor/hps" model, we should be able to calculate how many hits it takes to break a shield.  I did a test in game and compared it to the number of hits it should take to break several shields.  I have the calculated hits (based on our formula) vs the actual hits it took to break them:

MW Kite Shield- Calculated hits: 38.42   Actual hits: 36
Heavy Round Shield- Calculated hits: 26.84  Actual hits: 23
Knightly Heater Shield- Calculated hits: infinity (negated)  Actual hits: 29
Knightly Kite Shield-  Calculated hits: infinity      Actual hits: 42

So for the most part, armor behaves by negating the damage caused to it, as predicted. (as seen in the Kite and Round shields...behaved as predicted!). 

However, if the armor on the shield is higher than the damage caused, it does NOT negate all the damage.  The armor bust be behaving differently here.  I wonder how?

(note: there is bound to be some randomness to the damage caused, the distance the attacker is to the shield, etc.  This preliminary test gives us an idea though.)

[Digglez]

the lower the powerstrike the less variable incoming damage will be.  also make sure attacker isnt holding attacks ever, just single click then let go...and stationary

[Cyclopsided]

Armor isn't a 1 for 1 damage increase. There's a formula I'm sure, and I don't know it.

[Penitent]

Armor isn't a 1 for 1 damage increase. There's a formula I'm sure, and I don't know it.

oh, well that's what I'm wondering!

[San]

Treat shield armor as body armor.

Use the damage calc to determine average damage on your shield: http://infinitum.dyndns.org/crpg/calc.htm

Every point in shield reduces damage by 8%. At 5 shield skill it's 40% reduction, so you can do: (dmg * .6) I think, the final shield damage.

Then do (total shield hp) / final shield damage.

For knightly heater, it's 33 body armor and 232 hp.

I used 4 PS, 28 cut. 74 wpf on 33 body armor is 14.5 damage. That comes to around 26.67 hits
I assumed there would be slight wpf reduction, so an effective 65 wpf would come out to 13.5 damage on average. With shield skill damage reduction, it came out to 28.64 hits.

[Phew]

The math also works out so that even though each shield skill only reduces damage by 8%, overall your shield takes about 15% more hits to break per additional shield skill (linearized about 5 shield skill).

Also, the math supports that heirlooming your shield is a good investment. At +3, most shields gain durability roughly equal to having 2-3 higher shield skill (the lower the shield's base HP, the more relative benefit you get from looming), in addition to increased speed. Compare that to heirlooming your weapon to +3, which acts like having about 1 higher power strike in most cases.

I like to think about looming in terms of equivalent free skill points, which illustrates why you should always loom armor before weapons. +3 armor is like getting 3-5 free points in Ironflesh! (linearized about medium armor vs. 2h sword). Would you rather trade 3 generations for 1 skill point in power strike or 4 skill points in Ironflesh?

Yes, I spend hours with the damage calculator San linked...