Rank the Alternate and Single Tap mods

[rikimasan]

The alternate mod only adds a tapping restriction to force a full alt playstyle. It is practically a do nothing mod for those who already play full alt. It should be ranked.

[tsunyoku]

If we're ranking Alternate doesn't it make most sense to rank Single Tap too? It's the same concept, just doing opposite things... neither should affect PP so I don't see this being any different than other ranked mods such as Muted.

[tsunyoku]

Approving from a committee perspective - still requires input from the client team.

[Detze]

The Alternate mod changes gameplay by acting as a conditional tap blocker, making it advantageous compared to not using the mod in situations where the player does not want to tap while possibly still tapping physically. Advantage would be easy to observe when using Alternate together with a mod that punishes extraneous taps with a Miss. The Alternate mod allows aiming differently, as well as tapping differently on overlapping notes, as it can be used to convert between tapping rhythms, especially when rebinding the keys in a specific order and using more than two keys to tap. There are countless examples of how this can result in an output that would not be possible when not using the mod with the same physical input:

• it is possible to tap at x BPM by tapping at 1.5*x BPM while playing with 3 keys, or by tapping at 2*x BPM while playing with 4 keys, with keys rebound in a specific order, or by alternating keys only every second tap while playing with 2 keys
• isolated doubles can be played by appropriate singletaps and triples
• the finger-control pattern of repeating single-then-double can be played as repeating quads
• repeated doubles can be played as streams while playing with 3 keys
• ...and many more.

In fact, with Alternate it is possible to play any finger-control pattern by streaming at the same BPM using keys in an appropriate order. The mod also corrects disadvantageous repeated taps of a key, which can be used to improve accuracy / avoid missing compared to not using Alternate. One example would be mashing with Rapid Trigger set up to be very sensitive, and another playing with more than two keys, as avoiding repressing the previously pressed key during depressing it due to limited finger independence would no longer be necessary.

In the pp algorithm there does not seem to be any accounting for gameplay patterns which are only possible with Alternate, so using Alternate should probably result in a pp and score penalty.

[rikimasan]

The Alternate mod changes gameplay by acting as a conditional tap blocker, making it advantageous compared to not using the mod in situations where the player does not want to tap while possibly still tapping physically. Advantage would be easy to observe when using Alternate together with a mod that punishes extraneous taps with a Miss. The Alternate mod allows aiming differently, as well as tapping differently on overlapping notes, as it can be used to convert between tapping rhythms, especially when rebinding the keys in a specific order and using more than two keys to tap. There are countless examples of how this can result in an output that would not be possible when not using the mod with the same physical input:

• it is possible to tap at x BPM by tapping at 1.5x BPM while playing with 3 keys, or by tapping at 2x BPM while playing with 4 keys, with keys rebound in a specific order, or by alternating keys only every second tap while playing with 2 keys
• isolated doubles can be played by appropriate singletaps and triples
• the finger-control pattern of repeating single-then-double can be played as repeating quads
• repeated doubles can be played as streams while playing with 3 keys
• ...and many more.

In fact, with Alternate it is possible to play any finger-control pattern by streaming at the same BPM using keys in an appropriate order. The mod also corrects disadvantageous repeated taps of a key, which can be used to improve accuracy / avoid missing compared to not using Alternate. One example would be mashing with Rapid Trigger set up to be very sensitive, and another playing with more than two keys, as avoiding repressing the previously pressed key during depressing it due to limited finger independence would no longer be necessary.

In the pp algorithm there does not seem to be any accounting for gameplay patterns which are only possible with Alternate, so using Alternate should probably result in a pp and score penalty.

I am not really seeing the abuse case practically.

For this to be relevant you would need to have the patterns be stacked, otherwise this already exists. You just send the extra tap into nothing. When things are stacked, you would still need to read the pattern correctly to know to do the abuse and learn to play improperly all so you can burn extra stamina tapping when you didn't need to?

If I'm missing something, would you be able to create a short example beatmap or link an existing one that I can play to see what you mean?

Edit:
Going through your examples, for reasons mentioned above I will assume that these are stacked patterns since if they aren't you could have extra taps without alternate as well and it would still work.

it is possible to tap at x BPM by tapping at 1.5x BPM while playing with 3 keys, or by tapping at 2x BPM while playing with 4 keys, with keys rebound in a specific order, or by alternating keys only every second tap while playing with 2 keys

I think you're suggesting that you can stream keys/2 * bpm for input but have it so excess keys have their inputs eaten by the alternate mod? This just means you're still streaming the correct bpm on the 2 active keys. Non-issue.

• isolated doubles can be played by appropriate singletaps and triples

wasn't sure what you meant by isolated, if it was just a double in a vacuum you can tap whatever you want after the double.

• the finger-control pattern of repeating single-then-double can be played as repeating quads

intended rhythm: L   R L   L   R L
cheesed rhythm:  L L R L   R R L R

I don't see the way you bind your keys for this to work.

• repeated doubles can be played as streams while playing with 3 keys

intended rhythm: L R   L R
cheesed rhythm:  L R R L R

I can see this working for someone playing on 3 keys but I don't see how it is easier to learn to swap to playing 3 keys for repeated doubles?
Also, this same behavior can be reproduced by having the 3rd key being unbound entirely without the alternate mod...

All the different ways to create cheese seem like they require a significant learning effort and are limited to abuse in only 1 pattern type to the point that it's easier to just actually learn to play the pattern.

[Hiviexd]

If this is going to happen, there also wouldn't be an issue with ranking Single Tap in osu!taiko too FWIW.

[bdach]

I have no opinion on this, but I see 3 upvotes on the OP, an approval from the pp committee, and the only dissenting voice appears to be @Detze with no support. So using democracy rules this can probably be considered.

@ppy/team-client does anyone have anything to say here?

[Lawtrohux]

Taiko-side pp committee is happy too.

[rikimasan]

@bdach 2 days without comment = LGTM, ship it :^)

Edit: was meant to be light hearted way to thread bump, my apologies

[Detze]

The abuse case would be a newly-enabled gameplay pattern requiring less finger-control (or even aim-control) skill to achieve the same or better result.

this same behavior can be reproduced by having the 3rd key being unbound entirely without the alternate mod

The purpose of the examples was to show that the Alternate mod changed gameplay by allowing gameplay patterns that would not be possible without using Alternate with the same settings. In certain cases, indeed an equivalent effect is achievable without Alternate with different settings. However, to prove there is no harm ranking an input-blocking mod without penalty, all scenarios have to be shown to not be advantageous compared to not using the mod, not just the examples given. For Single Tap, this is clear, but for Alternate, it is not.

Unbinding a key will provide an equivalent effect without Alternate only if one iteration of the repeating physical tapping pattern is cyclic with respect to the number of keys. If it is not, then this idea isn't possible, and Alternate enables a novel way of tapping a pattern.

When things are stacked, you would still need to read the pattern correctly to know to do the abuse and learn to play improperly all so you can burn extra stamina tapping when you didn't need to?

The cognition overhead is not a meaningful obstacle at all, the pattern can be memorized if not read. It can take more skill to withhold taps at certain rhythms compared to simply streaming, that's the whole point of the finger-control skillset. That's why before ranking Alternate it should be considered whether the newly-enabled gameplay patterns introduce any new advantages.

Even if not every pair of notes in the game is overlapping, the fact that some are and Alternate could provide a novel way to obtain an advantage while playing them would be enough grounds to award a penalty to the mod, IMO.

All the different ways to create cheese seem like they require a significant learning effort and are limited to abuse in only 1 pattern type to the point that it's easier to just actually learn to play the pattern.

[citation needed]
There are players who normally use 3 or 4 keys to play (it is a natively supported playstyle in osu!lazer afterall), for whom it might not be a problem to tap in a newly-enabled manner. As stated above, withholding presses can be more difficult, so 'more presses' does not necessarily mean 'more difficult'. It is not at all clear that none of the newly-enabled gameplay patterns are not more difficult.

Using Alternate also might improve mashing accuracy (which is already a common pp cheese), since if one key is pressed twice in a row, then its hit is probably inaccurate. This should also be considered.

An additional tap can be also accidental and lead to a Miss/non-Great, which is not uncommon and Alternate could nivellate. I am not a fan of the use of Alternate being encouraged like this, as well as having the choice without downsides to enable different possible ways to hit the beatmap's (overlapping) notes from the usual ones without Alternate.

I see 3 upvotes on the OP, an approval from the pp committee

The osu! pp committee's approval is from before this discussion (as well as several upvotes).

It is unfortunate that the ranking of Alternate and Single Tap is coupled together in one PR. I have concerns only about ranking Alternate without penalty, not Single Tap, as there is of course nothing wrong with ranking the Single Tap mod without penalty. Note that the Alternate mod does not exist for Taiko, only osu!.

[bdach]

@rikimasan I'm in no particular hurry here. Please save such comments to yourself, thanks.

[stanriders]

@smoogipoo any reason this was changed to pp-dev? Pretty sure mod becoming ranked shouldn't really be tied to a diffcalc release

[smoogipoo]

That was a mistake. May be others because I went through all PRs in the project tracker.