Implement stamina consideration for Mono (single-coloured) patterns.

[Lawtrohux]

Upon the release of the most recent rework, stamina has once again been reworked with a fix for certain mapsets that contain stupidly high bpm, single coloured patterns out of the scope of the assumed concepts behind the stamina system.

• Introduces a monoStaminaFactor that essentially outputs a percentage of single-color (mono) patterns within a map. This factor is used to adjust the difficulty where mono patterns are identified by strain to be the only difficulty of the map (e.g., maps like StrangeProgram have a 100% monoStaminaFactor).
• Scaling now reflects this value, factoring in the monoStaminaFactor to penalise mono-heavy maps performance side.
• Flashlight bonus multiplier is also now scaled by this attribute, if monoStaminaFactor is of a high value, less of a bonus will be applied
• Moved the isConvert bool outside of difficulty value only, and disables the specific global mod bonuses pertaining to converts.
• Easy has been given a harsher penalty, to adjust to the new statistical accuracy changes.

The design is that maps without this very specific consideration are mostly unaffected, meaning that regular mapsets should see no change, returning either a very low value of monoStamina, or for most, a total value of 0.

Some examples of scores that are changed by this directly are:
Halti's StrangeProgram score
Live: 1410.7
Rework: 860.2
Change: -550.5

Ney's Alive score
Live: 1123.8
Rework: 823.5
Change: -300.3

Ney's Mad Machine score
Live: 843.2
Rework: 663.1
Change: -180.1

Full credits to @Natelytle for the concepts of this fix.

[smoogipoo]

NaN value generated on https://osu.ppy.sh/beatmapsets/717343#osu/1537214 :

ruleset: taiko

╔════════════════════════════════════════════════════════════╤═══════════╤═════════╤══════════════════╤═══════════════════╤═════════════════╤═════════════════╤═══════════════╤════════════════╤═════════════╗
║beatmap                                                     │star rating│max combo│stamina difficulty│mono stamina factor│rhythm difficulty│colour difficulty│peak difficulty│great hit window│ok hit window║
╟────────────────────────────────────────────────────────────┼───────────┼─────────┼──────────────────┼───────────────────┼─────────────────┼─────────────────┼───────────────┼────────────────┼─────────────╢
║1537214 - Kizuna AI - FUCK YOU! (Kawashiro) [Moa's Beginner]│       0.21│     3.00│              0.00│                NaN│             0.00│             0.12│           0.12│           45.50│       108.00║
╚════════════════════════════════════════════════════════════╧═══════════╧═════════╧══════════════════╧═══════════════════╧═════════════════╧═════════════════╧═══════════════╧════════════════╧═════════════╝

[smoogipoo]

Have applied my own fix to the NaN values so I can have a good state for spreadsheet gen. Feel free to adjust as necessary.

!diffcalc
RULESET=taiko

[github-actions]

Target: #30460
Spreadsheet: https://docs.google.com/spreadsheets/d/1ipeHlZpWZ6_OaouatD66DImwZaQEezBJ73M-bzBd_is/edit

[Natelytle]

The fix is good, just an oversight on my part.

[smoogipoo]

@tsunyoku @peppy how do you two feel about this? Personally I don't think it's too much, but it is more than just a hotfix.

It needs:

• A new DB attribute (29).
• A diffcalc rerun (taiko).
• A ppcalc rerun (taiko).

The other option is my alternative PR (#30456) which restores older code and is easier to digest as a "hotfix", but that will still require diffcalc + ppcalc reruns.

[tsunyoku]

Given #30456 (comment), I think there's an interest in pushing your convert PR as well as this.

I agree that this is definitely more than a hotfix, however taiko is going to require a full rerun regardless (as mentioned) so I'm not necessarily concerned about that as the changes are simple enough. I can't imagine this causing further issues as this can only nerf values, and we're not introducing an entirely new skill or anything like that.

All things considered, I think this should be fine.

The alternative would be deploying smoogi's hotfix immediately, and then later bringing in this one when things are more settled. However, I'm not convinced this is going to be particularly useful as it will require monitoring another deploy just for a relatively small fix and these 2 changes combined are likely to produce more satisfactory values. We're probably better pushing both changes or nothing in my opinion, unless this change is rejected by the taiko committee for unrelated reasons (which I don't see happening).

[peppy]

Hmm, let's get this in and run a recalc, then see what people are saying.

[peppy]

@tsunyoku can you confirm that @smoogipoo 's change should also be merged in for release, by your intuition?

[tsunyoku]

@peppy yes, smoogi's fix should be included