fix: extra validator for maimai DX score verification

[j1nxie]

checked up with a few friends and 100.5% seems to be the minimum for an ALL PERFECT score, so adding it as a validator for scores.

there isn't a validator for the other way around since scores higher than 100.5% can be not ALL PERFECT.

[zkrising]

can you explain the maths behind this? if it's always the case for now and every future chart, then yeah

[beer-psi]

To put simply, the 101% in maimai DX scores is split into 2 parts: 100% base score and 1% break bonus.

All note types (tap, hold, slide, touch, break) award full base scores on PERFECTs, no surprises here.

However, break bonus varies based on how precise a break note was hit, with the minimum bonus for a PERFECT hit being half of full bonus.

Assuming all breaks were hit with minimum bonus, that leaves us with 1 / 2 = 0.5% break bonus => 100.5% score being the minimum for ALL PERFECTs.

This doesn't apply the other way around (100.5+ does not mean an ALL PERFECT) because you could get higher break bonuses and use that to tank the losses from hitting non-perfects.

More details on the maimai DX scoring system: https://github.com/SpiritsUnite/maimai-score-details#maimai-scoring-system

[zkrising]

what if a chart has no breaks?

[beer-psi]

all official charts are guaranteed to have at least one break, it's been 10 years of maimai and no charts with zero breaks exist.

[j1nxie]

to be fair, we support only official charts from SEGA, which will clearly guarantee at least 1 break note, due to the fact that the game checks for 101% for ALL PERFECT+ lamps. in which case, 100.5% being the minimum for ALL PERFECT will also apply.

[zkrising]

ok, but what happens if there was a chart with no breaks in the future?

[j1nxie]

then at that point, fuck SEGA, and we might have to drop all the validators at that point, since if that was the case the max score would be 100% and AP+ validation would be removed too.

[zkrising]

i think it's more likely that in the 0 breaks case you end up with +1% for breaks no matter what. has anyone actually tested this is what i'm getting at

[zkrising]

bad news: no breaks => 100% max. technically speaking maimaidx has a chart dependent max, but do we care? do you care? i don't. sega don't care either. nobody cares.