Mana cost rounding errors.

[nikitkuzi]

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What platform are you running Path of Building on?

Windows

What is the value from the calculation in-game?

1. Craclking lance of Disintegration level 3 (15 base mana cost) with CWDT support (2.5 multi) + enhance (1.2 multi) + conc effect (1.4 multi). Total mana cost should be 63
2. Craclking lance of Disintegration level 2 (14 base mana cost) with CWDT (2.5 multi) + enhance (1.2 multi) + archmage with 850 max unreserved mana. Total mana cost should be 168

What is the value from the calculation in Path of Building?

1. Craclking lance of Disintegration level 3 (15 base mana cost) with CWDT support (2.5 multi) + enhance (1.2 multi) + conc effect (1.4 multi). Total mana cost should be 63, but its 62 in POB. In the calculation tab it shows that it multiplies by 4.19999.
2. Craclking lance of Disintegration level 2 (14 base mana cost) with CWDT (2.5 multi) + enhance (1.2 multi) + archmage with 850 max unreserved mana. Total mana cost should be 168, but its 171 in the POB. In the calculation tab it shows that base mana cost is 57 (14 + 43). 43 comes from Archmange support with 850 unreserved mana. 850 * 0.05 = 42.5. So total base cost should be 56.

How to reproduce the issue

1. Craclking lance of Disintegration level 3 (15 base mana cost) with CWDT support (2.5 multi) + enhance (1.2 multi) + conc effect (1.4 multi). Total mana cost should be 63
2. Craclking lance of Disintegration level 2 (14 base mana cost) with CWDT (2.5 multi) + enhance (1.2 multi) + archmage with 850 max unreserved mana.

PoB for PoE1 build code

https://pobb.in/vUucOnSt7-P4

Screenshots

No response

[jokre33]

I wanted to add to this with another example:

My TS deadeye:

• PoB (pobb.in): https://pobb.in/GlAR21JdjdSZ
• Actual Character: https://www.pathofexile.com/account/view-profile/jokre33-0836/characters?characterName=JokreTShot

PoB Version: Beta 2.67.2 (latest on the weekly beta branch as of writing)

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Tornado Shot:

• in game Mana Cost: 11 (tested and actually removes 11 Mana) (tested with soul catcher: It removes 11 Mana every time, didn't have a single -10 even after 30 shots, so Mana Costs are definitely rounded)
• PoB Mana Cost: 10 in the side bar, 11 in Calcs (but 10 again if you click on it)
• calculated Mana Cost: 13 (base) * 4.2588 (support gems) * 0.58 (inspiration 21/30) / 1.3 (mana cost efficiency) - 14 (2x -7 on rings) = 10.70104

Frenzy:

• Working correctly: 6 everywhere
• calculated Mana Cost: 10 (base) * 4.4928 (support gems) * 0.58 (inspiration 21/30) / 1.3 (mana cost efficiency) - 14 (2x -7 on rings) = 6,0448

Blink Arrow:

• in game Mana Cost: 17
• PoB Mana Cost: 16 in the side bar, 17 in Calcs (but 16 again if you click on it)
• calculated Mana Cost: 20 (base) * 2 (second wind) / 1.3 (mana cost efficiency) - 14 (2x -7 on rings) = 16.7692307692

Snipers Mark:

• in game Mana Cost: 37
• PoB Mana Cost: 36 in the side bar, 37 in Calcs (but 36 again if you click on it)
• calculated Mana Cost: 33 (base) * 2 (mark on hit) / 1.3 (mana cost efficiency) - 14 (2x -7 on rings) = 36.7692307692

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I'm assuming this is an issue of truncating (or rounding down) vs "regular" rounding, since Frenzy (with a decimal below .5) is correct, while the other 3 (with decimals above .5) aren't.

[LocalIdentity]

@jokre33 your issue is fixed by #10254