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Apr 9 2023 10:51pm
bow zon using windforce

20fg to someone who can explain this to me in simple terms that a special person can understand. I dont even want to try to research it because its going to go over my little head

ive been trying to hit higher frames with different combinations. I got a merc with faith.

so there is a certain frame i hit. I was trying to get to the that particular frame by equipping 30 more ias from gear to see if i could ditch the faith

i got the same frames with faith buff + the 30 ias. so i just took off 30 ias gear to add MF.

but then i heard of the runeword called hustle. so i made one

i proc the burst of speed and hit an entire other frame that i didnt even know about with the faith buff, which is cool

But i just wanted to hit the frame i was searching for ORIGINALLY w/o the 30 ias extra gear and/or ditching the faith. Burst of speed only grants 21% ias. Why do i get the extra frame with burst of speed but not from the 30 ias extra gear?



Finally. It also matters on my bow type? Even though windforce hydra bow has 40 ias. other bases can shoot faster with less ias? Im lost. Going to bed. Ill send 20 fg to someone who give me a clear answer, if thats possible
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Apr 9 2023 11:16pm
first of all attack speed does not change continuously with ias, but stepwise. thats why your attack speed only differs if you hit certain numbers (called breakpoints). secondly, the fanaticism aura from faith/beast rw and burst of speed calculate differently (they modify the attack rate and not the attack speed). long story short: calculating attack speed is a complicated multi-step process that no one does by hand. use one of these calculators:
D2L: https://d2.lc/IAS/
D2R: https://warren1001.github.io/IAS_Calculator/

you have to plug in your class, weapon base type and attack/skill (yes, all of that does have influence on the result...) as well as fana lvl and BoS lvl. you will then get a table which lists how much is you will need for certain breakpoints, the lower the breakpoint the faster your attack (given numbers are frames, that means the time between two consecutive attacks. that's why you want them to be low). keep in mind that the total ias needed can come from any gear (or weapon-only if listed) except the numbers for fana and BoS (bc they already change the table itself, as previously mentioned)

I hope this is good enough for a rough explanation. if you have further questions, just ask
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Apr 9 2023 11:44pm
Quote (reggaeman23 @ 10 Apr 2023 06:51)
bow zon using windforce

20fg to someone who can explain this to me in simple terms that a special person can understand. I dont even want to try to research it because its going to go over my little head

ive been trying to hit higher frames with different combinations. I got a merc with faith.

so there is a certain frame i hit. I was trying to get to the that particular frame by equipping 30 more ias from gear to see if i could ditch the faith

i got the same frames with faith buff + the 30 ias. so i just took off 30 ias gear to add MF.

but then i heard of the runeword called hustle. so i made one

i proc the burst of speed and hit an entire other frame that i didnt even know about with the faith buff, which is cool

But i just wanted to hit the frame i was searching for ORIGINALLY w/o the 30 ias extra gear and/or ditching the faith. Burst of speed only grants 21% ias. Why do i get the extra frame with burst of speed but not from the 30 ias extra gear?



Finally. It also matters on my bow type? Even though windforce hydra bow has 40 ias. other bases can shoot faster with less ias? Im lost. Going to bed. Ill send 20 fg to someone who give me a clear answer, if thats possible


1. Items adds IAS, while skills adds SIAS (skill's ias).
2. IAS from items is converted to EIAS (effective ias) which have diminishing return.
3. After that, EIAS and SIAS are summed, making SIAS much more effective then IAS from items because SIAS isn't affected by previous diminishing return of the calculation.

AnimationDuration = ceiling((AnimationLength * 256) / flooring(256 * (1 + SIAS + EIAS - WeaponSpeedMod) / 100)) -1
where EIAS = flooring(120 * IASItem / (120 + IASItem)) <- that's diminishing return's calculation

For example 60 IAS is equal to 40 EIAS
60IAS = 40EIAS = 40SIAS
30IAS = 24EIAS = 24SIAS

Some weapons have additional penalty. Example throwing potions. However Barbarian isn't affected by that penalty.
Also there are different animationsLenght for some skills, also if few skills the calculation formula changes slightly.


This post was edited by olrios on Apr 10 2023 12:02am
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Apr 10 2023 03:37am
Quote (reggaeman23 @ Apr 10 2023 07:51am)
bow zon using windforce

20fg to someone who can explain this to me in simple terms that a special person can understand. I dont even want to try to research it because its going to go over my little head

ive been trying to hit higher frames with different combinations. I got a merc with faith.

so there is a certain frame i hit. I was trying to get to the that particular frame by equipping 30 more ias from gear to see if i could ditch the faith

i got the same frames with faith buff + the 30 ias. so i just took off 30 ias gear to add MF.

but then i heard of the runeword called hustle. so i made one

i proc the burst of speed and hit an entire other frame that i didnt even know about with the faith buff, which is cool

But i just wanted to hit the frame i was searching for ORIGINALLY w/o the 30 ias extra gear and/or ditching the faith. Burst of speed only grants 21% ias. Why do i get the extra frame with burst of speed but not from the 30 ias extra gear?



Finally. It also matters on my bow type? Even though windforce hydra bow has 40 ias. other bases can shoot faster with less ias? Im lost. Going to bed. Ill send 20 fg to someone who give me a clear answer, if thats possible


Bcoz if you ask from Blizzard 1 + 1 is not 2, it’s 1,5.
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Apr 10 2023 12:58pm
Quote (Soppamies @ Apr 10 2023 05:37am)
Bcoz if you ask from Blizzard 1 + 1 is not 2, it’s 1,5.


blizzard does love their diminishing returns even in other games
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Apr 12 2023 09:31am
EIAS is what is used to determine a FPA.
FPA = Frames Per Attack.

Basicly meaning that an attack use forexample 7 frames to perform an attack.
But the hit itself can hit before the 7th frame.
Quote (olrios @ Apr 10 2023 07:44am)
1. Items adds IAS, while skills adds SIAS (skill's ias).
2. IAS from items is converted to EIAS (effective ias) which have diminishing return.
3. After that, EIAS and SIAS are summed, making SIAS much more effective then IAS from items because SIAS isn't affected by previous diminishing return of the calculation.

AnimationDuration = ceiling((AnimationLength * 256) / flooring(256 * (1 + SIAS + EIAS - WeaponSpeedMod) / 100)) -1
where EIAS = flooring(120 * IASItem / (120 + IASItem)) <- that's diminishing return's calculation

For example 60 IAS is equal to 40 EIAS
60IAS = 40EIAS = 40SIAS
30IAS = 24EIAS = 24SIAS

Some weapons have additional penalty. Example throwing potions. However Barbarian isn't affected by that penalty.
Also there are different animationsLenght for some skills, also if few skills the calculation formula changes slightly.


This, but also:
Sequence attacks can have wsm penalties.
Like forexample jab, it has 30wsm penalty.

Some attacks also has next delay:
https://forums.d2jsp.org/topic.php?t=81090548&f=87

Baseframe is the same as AnimationLenght in this formula.
Hitframe is when u actually hit, some attacks use that value instead of baseframe. Some wepons/animations have a different animation speed, example is assassin attacking with claws. Which is 208. Casting traps, kics etc use the standard 256 even though claws are used.
AnimationDuration is usually called FPA here(frames per attack).

It's also worth to mention the breakpoint system is 25frames.
So if u have a 7fpa attack with hitframe on 6 it means u do 25/7 = 3,57 attacks per second.
Meanwhile ur attacks will land at frame 6, 12, 18, 24 etc...

The cap for EIAS is usually 75, meanwhile werewolf and werebear has 150 cap.
Frenzy, Dragon claw, double swing, double throw has Velocity Increase instead of EIAS. Their cap is 150. It's a different formula as well.

Slow also affect EIAS. Just subtract it like with wsm.

The only dimishing return value is IAS.

Here is a pretty good explanation, even though its a little outdated for werewolf the explanations are good :)
https://forums.d2jsp.org/topic.php?t=92642105&f=148

Actually found an old guide now:
https://forums.d2jsp.org/topic.php?t=89662420&f=148

This post was edited by gel87 on Apr 12 2023 09:42am
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Posts: 9,333
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Apr 12 2023 11:01am
Quote (gel87 @ Apr 12 2023 08:31am)
EIAS is what is used to determine a FPA.
FPA = Frames Per Attack.

Basicly meaning that an attack use forexample 7 frames to perform an attack.
But the hit itself can hit before the 7th frame.

This, but also:
Sequence attacks can have wsm penalties.
Like forexample jab, it has 30wsm penalty.

Some attacks also has next delay:
https://forums.d2jsp.org/topic.php?t=81090548&f=87

Baseframe is the same as AnimationLenght in this formula.
Hitframe is when u actually hit, some attacks use that value instead of baseframe. Some wepons/animations have a different animation speed, example is assassin attacking with claws. Which is 208. Casting traps, kics etc use the standard 256 even though claws are used.
AnimationDuration is usually called FPA here(frames per attack).

It's also worth to mention the breakpoint system is 25frames.
So if u have a 7fpa attack with hitframe on 6 it means u do 25/7 = 3,57 attacks per second.
Meanwhile ur attacks will land at frame 6, 12, 18, 24 etc...

The cap for EIAS is usually 75, meanwhile werewolf and werebear has 150 cap.
Frenzy, Dragon claw, double swing, double throw has Velocity Increase instead of EIAS. Their cap is 150. It's a different formula as well.

Slow also affect EIAS. Just subtract it like with wsm.

The only dimishing return value is IAS.

Here is a pretty good explanation, even though its a little outdated for werewolf the explanations are good :)
https://forums.d2jsp.org/topic.php?t=92642105&f=148

Actually found an old guide now:
https://forums.d2jsp.org/topic.php?t=89662420&f=148


Thanks for the simple explanation. 🤣
Sounds like I'd have to take a college class to understand ias in d2

This post was edited by reggaeman23 on Apr 12 2023 11:01am
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Apr 18 2023 09:22pm
https://warren1001.github.io/IAS_Calculator/
just use this and youll be fine tells you the ias you need from items gear etc
tells you your bps and all that good stuff
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