Hi,
I hope, this is the right place to post this. A Member of the German Shaman Forums gave me the link, so that i can get some feedback for my math. I hope you all can understand, or at least follow me, because my english is not the best.
I thought a while about how Windfury works in connection with dual wield in a mainly mathematical manner, though i made a few tests for getting some hints. I think i now got the right formula for calculating windfury especially in conjunction with Stormstrike.
I think the only way to calculate a chance for a windfury proc is by calculating the number of strikes a windfury proc occur in average. The Number of Hits consist of the hits which are usually done during the 3 second cooldown and the expected value of the procchance when a wf proc is possible.
Pwf=1/(X+N)
Pwf is the procchance, X is the "Magic number" and N is the number of strikes during the cooldown.
Calculation of N:
First i'll introduce the direct way of calculating N without stormstrike(with, its much more complicated). When a Weapon starts a windfury, it resets its swingtimer, so with a 2.2 weapon we have to wait 2.2 seconds until the weapon may attack again, so it will allways strike once during the 3 seconds, never 2 times. The weapon in the other hand isn't in such a well defined state, there could be one or 2 attacks.
When both Weapons have the same speed, the Formula for N is:
Ws=Weaponspeed
N=floor(3/Ws)+3/Ws
With two different speeds, it starts to get complicated. Mainly its the same formula but we have to weight it with the weaponspeeds. While a 1.6 weapon strikes only once during the 3sec cooldown when it produces a windfury proc, it might do 2 strikes, when the other hand procs.
Wm=weaponspeed Main Wo=weaponspeed off
P=the chance the main/offhand weapon procs windfuror. the higher the speed difference, the higher the chance
Pm=1/(Wm/Wo+1)
Po=1-Pm
N=Pm*(floor(3/Wm)+3/Wo)+Po*(floor(3/Wo)+3/Wm)
The Magic Number cannot be directly calculated, but it can be tested. I made these tests(i don't want to waste your time with these stupid stochastic calculations), and X seems to be 3.
This works very well and so one can say that the WF procchance is nearly 33%.
Ok, now the easy part ends. This calculation only works, when you don't ever dare to use stormstrike, stormstrike changes the procchance!
first of all, lets calculate the damagebonus a stormstrike gives. It's mainly a calculation of how much damage the 2 additional attacks do compared to the normal damage.
SSBonus=(10*hitchance/Wm+10*hitchance/Wo+2*yellowhit)/(10*hitchance/Wm+10*hitchance/Wo)-1
the Damagebonus gets more accurate, when you use a 11 instead of a 10, because one cannot use SS every 10 seconds due to lag and other bad things.
What happens, when stormstike is used? 3 things might happen:
1. The stormstrike is done in the 3second cooldown. no wf can occur
2. The stormstrike procs wf
3. The stormstrike can proc wf but doesn't (due to bad luck

)
Point 1 and 2 have to be added to N.
The first one is done by multiplying N with the SSBonus. When stormstrike increases the damage by x%, the strikes also have to be increased by the same amount. Though we don't know, when a wf proc occurs(we get this information with a small delay, like 0,5sec), we have to assume that we geht x% more strikes during the 3second cooldown.
What happens in the second case?
when stormstrike procs wf, bot weapon swingtimer aren't defined, so we cannot say that any weapon does only 1 strike in the following 3 seconds. so we have to add a calculation for that.
SSN=SSBonus*(3/SM+3/SO)+(1-SSBonus)(1+SSBonus)*N
=SSBonus*(3/SM+3/SO)+(1-SSBonus^2)*N
The SSBonus*(3/SM+3/SO)+(1-SSBonus) part is for case 2, (1+SSBonus) is for case one.
I hope, you could understand me, and that this calculations can help to improve the damage calculations for shamans
