Craft skill formulas

[Akrion]

Does anybody happen to know how the creator of the Craft Calculator came to the formulas for calculating craft efficiency based on skill? I'm looking specifically for how I can calculate required resources for construction, as I've been working on a construction calculator of sorts and right now it's assuming optimal.

[Chasing]

The calculation is

(Optimal efficiency - Minimum Efficiency) / (Optimal Resource Amount - Minimum Resource Amount) = Skill Efficiency Step Amount.

You then add the Skill Efficiency Step Amount to the Minimum Efficiency until you hit Optimal Efficiency (this should match the difference between optimal and minimum resources needed).

Each time you add a step you need to round the result upwards. So if an answer was 160.1 then the result would be 161 (160.2 = 161 etc).

You can't round the Efficiency Step Amount as it will skew the result.

For construction its a little easier as you only have 3:1 and 2:1 ratios across all the building components so there is only one step.

Also to note is that not all buildings have the same XP requirement for placing the same resource as other buildings (Have a look at T6 storehouses vs a T6 silo).

[Akrion]

Thank you, Chasing! :3

[Chasing]

Just realised I said 'XP requirement' I meant 'skill requirement'

[Akrion]

Just realised I said 'XP requirement' I meant 'skill requirement'

You also wrote (Optimal Resource Amount - Minimum Resource Amount) when I can only guess you mean (Maximum resource Amount - Minimum Resource Amount) .. ?

Also it doesn't seem to add up correctly if you round the result up each time you add a step. It only seems to work when you round up after adding every step.

(Opt Eff. - Min Eff.) / (Max Res. - Min Res.) = Skill Eff. Step

Skill Eff. Step * Step count + Minimum Eff. = Result to be rounded up.

[Chasing]

Yep my grammar/language,

when referring to minimum resource amount that means the most resource at minimum skill

Lets see if I can explain with an example

Chainmail Mithril Belt

Minimum Skill is 900 (18 bars), Optimal skill is 1100 (9 bars)

(Optimal efficiency - Minimum Efficiency) / (Optimal Resource Amount - Minimum Resource Amount) = Skill Efficiency Step Amount.

(1100-900) / (18-9)
therefore
(200) / (9) = 22.22222222r

So 9 steps to go from 18:1 to 9:1

18:1 = 900
17:1 = (900 + 22.22222222r) = 922.2222222r = 923 rounded
16:1 = (922.2222222r + 22.2222222r) = 944.444444r = 945 rounded
15:1 = (944.444444r + 22.2222222r) = 966.666666r = 967 rounded
14:1 = (966.666666r + 22.2222222r) = 988.888888r = 989 rounded
13:1 = (988.888888r + 22.2222222r) = 1011.111111r = 1012 rounded
12:1 = (1011.111111r + 22.222222r) = 1033.333333r = 1034 rounded
11:1 = (1033.333333r + 22.222222r) = 1055.555555r = 1056 rounded
10:1 = (1055.555555r + 22.222222r) = 1077.777777r = 1078 rounded
9:1 = (1077.777777r + 22.222222r) = 1100

If you check this against HCC you can see it matches.

Sorry I didnt explain it clear enough.

[Akrion]

After a bit of thinking and fiddling around, along with some help from Raptress, I was able to accomplish what I was looking for:

step = (maxSkill - minSkill) / (maxRes - minRes);
tier = (currSkill - minSkill) / step;
efficiency = ceil(maxRes - tier);

Now I can calculate resource efficiency based on current skill and chosen tier. Thanks again for the step formula, Chasing.

Edit: A little background in how I came up with the above for those that might be interested:

I figured that the step should give you enough information to work with when you combine it with current skill to come up with resource efficiency, it was just coming up with a way to do it that took me a little while.

Ultimately I concluded that if you subtracted the minimum required skill of the tier you're working with from your current skill, you'll either have a positive number of how far past the minimum you are, a negative number of how far behind the minimum you are, or 0 (being at the minimum).

Once this hit me, the rest became fairly clear because now with the tier accounted for I'm left with the base skill points. Divide this base by the step and you get the step count. Then you just subtract the step count from the maximum required resources and you're left with current required resources.

Even better is that when you subtract minimum skill from current skill, you can be left with a negative. And when you put that number into (maxRes - tier), or (30 -(-5)) as an example, you get a number higher than the max, 35 in the case of the example, which can be used to determine skill being too low.