It's hard to create a really good ranking system, player skill is best judged by players imo. Nevertheless, there are some things you can do to create at least a decent ranking system.
Ideas for a decent ranking system:If only osu!mania maps would count towards ranking, the system would already be 50x better than the previous one.
This isn't necessary though if you have a system where players get more pp for performing well on harder maps.
The difficulity here is determining how hard a map is. Density is one thing but it's not very accurate to determine difficulity by just that. There might be one specific point in the map where it is a lot harder than the rest, or there may be a lot of LN walls. LN walls of density 9 can be harder than normal maps of density 11 imo. It is imo almost impossible to make a system that judges difficulty perfectly, but this is definitely not necessary for a good ranking system. Just keep some key concepts in mind next to density (like bursts, LN, jacks, OD, HP etc) and you'll have a fairly good judgement system.
Another difficulity is determining
how much more pp you give for clearing hard maps compared to easy maps. For me, this is hard to put a number on. But I think the number should be there with the idea in mind that advanced players should be encouraged to play harder maps. This will probably involve a lot of trial and error.
Other things:Not everyone is obsessed with accuracy, some players like to hard clear so I don't think you should put too much emphasis on accuracy.
(ofcourse, 99.5% should be worth a lot more than 90%, but not like 100x more). This is also clearly not linear: 95% to 100% is much harder than 90% to 95%. But do not exaggerate on this else you will force players into becoming obsessed with accuracy. Accuracy is important yes, there's nothing wrong with that playstyle, but players shouldn't be forced into it.
DT and HR (only those two mods) should earn you more score and thus more pp imo.
The bonus score system on key modes is fine imo since they are only for autoconverts and if you implement a system where clearing hard maps would earn you more than easy maps, autconverts become worthless for more experienced players anyway. Although this does give a false sense to newer players that lower keymodes are easier so you might want to give it some tweaks.
I think it might be a good idea to only let a players top 100 (or so) performances count towards pp. This would make it unfarmable. The one and only way to increase pp should be to increase your actual player skill. Also a system like this would make determining
how much more pp you give for clearing harder maps a much easier process since as long as you give
even a little bit more pp for clearing harder maps, players will already be encouraged to play harder maps because they can't improve their pp gained from their 100 easy maps anymore. The number would then just represent how important you think accuracy is.
Also basically all of this is very well put:
Aqo wrote:
- average map density
- peak density for a 3~8 seconds length of the hardest part of the map
- amount of jacks and how long/fast jacks are they
those are the main 3 things that make mania charts hard to get a good result on; and they're often absent in most autoconverts, which leads those autoconverts to just be an acc-farm-fest.
there -ARE- some autoconverts that are hard and deserve rank imo, like extreme fantasy, dj amuro - F, etc
but either way, stuff like A ranks on much harder charts should be worth more than S ranks on very easy charts. The algorithm should be able to determine "difficulty of getting S" per chart based on the 3 above criteria and awards points accordingly, where a B rank gives roughly no points (because you can pretty much just mash fast enough and get B on most things), A rank (90-95) gives a fair amount of points depending on amount of bads and eventually S ranks giving much more but with a more linear addition from extra acc.
yes, SS is -much- harder than 97% on the same chart, but SS [Normal] shouldn't beat 95% [Hard] or SS [Hard] shouldn't beat 95% [Insane] and so on. (the difficulty names are just to illustrate difficulty progression. difficulty names are pretty much meaningless in mania, not hard to find something called [Easy] harder than most ranked [MX] charts lol)