rosu-pp-py

Difficulty and performance calculation for all osu! modes.

This is a python binding to the Rust library rosu-pp which was bootstrapped through PyO3. Since all the heavy lifting is done by Rust, rosu-pp-py comes with a very fast performance. Check out rosu-pp's README for more info.

How to use rosu-pp-py

The library exposes three classes: Calculator, ScoreParams, and CalculateResult.

1. The first step is to create a new Calculator instance by providing the constructor the path to a .osu beatmap file like so

calculator = Calculator('/path/to/file.osu')

2. Next, you need to create ScoreParams. It has the following fields:

- mods: Optional[int],          // bit value for mods, defaults to 0 (NM) see https://github.com/ppy/osu-api/wiki#mods
- acc: Optional[float],         // if neither acc nor hitresults are specified, acc defaults to 100.0
- n300: Optional[int],          // defaults to value based on acc
- n100: Optional[int],          // defaults to value based on acc
- n50: Optional[int],           // defaults to value based on acc
- nMisses: Optional[int],       // defaults to 0
- nKatu: Optional[int],         // only relevant for osu!ctb
- combo: Optional[int],         // defaults to full combo
- score: Optional[int],         // only relevant for osu!mania
- passedObjects: Optional[int], // only consider this many hit objects; useful for failed scores; defaults to all objects

Note that all fields are optional. If nothing is specified, the parameters are equivalent to the parameters of the best possible NM score. ScoreParams can be created either by calling the constructor without arguments and then set the fields manually like so

params = ScoreParams()
params.acc = 98.76

or they can be created by passing kwargs to the constructor directly like so

params = ScoreParams(acc = 98.76)

3. The last step is to provide the ScoreParams to the Calculator through the function calculate. This function takes one argument which must be either a single ScoreParams or an Iterable[ScoreParams], i.e. anything that python can iterate over like a list, set, ...

Example

from rosu_pp_py import Calculator, ScoreParams

calculator = Calculator('./maps/1980365.osu')

params1 = ScoreParams(
    mods = 8 + 16,  # HDHR
    acc = 97.89,
    nMisses = 13,
    combo = 1388,
)
params2 = ScoreParams(mods = 24)

[result] = calculator.calculate(params1)
results = calculator.calculate([params1, params2])
assert result == results[0]
print(f'PP: {results[0].pp}/{results[1].pp} | Stars: {results[1].stars}')

Return object structure

The Calculator::calculate function will provide you a list of CalculateResult, one for each score you specified parameters for. CalculateResult contains the difficulty and performance attributes. Most of its attributes are optional based on the map's mode. In the following, O/T/C/M will denote for which mode the given attribute will be present:

mode: int
    Gamemode of the map, 0=O, 1=T, 2=C, 3=M. (O/T/C/M)
stars: float
    Star rating of the map. (O/T/C/M)
pp: float
    Performance points of the score. (O/T/C/M)
ppAcc: Optional[float]
    Accuracy based portion of the performance points. (O/T/M)
ppAim: Optional[float]
    Aim based portion of the performance points. (O)
ppFlashlight: Optional[float]
    Flashlight based portion of the performance points. (O)
ppSpeed: Optional[float]
    Speed based portion of the performance points. (O)
ppStrain: Optional[float]
    Strain based portion of the performance points. (T/M)
nFruits: Optional[int]
    The amount of fruits in the map. (C)
nDroplets: Optional[int]
    The amount of droplets in the map. (C)
nTinyDroplets: Optional[int]
    The amount of tiny droplets in the map. (C)
aimStrain: Optional[float]
    Aim based portion of the star rating. (O)
speedStrain: Optional[float]
    Speed based portion of the star rating. (O)
flashlightRating: Optional[float]
    Flashlight based portion of the star rating. (O)
sliderFactor: Optional[float]
    Nerf factor for sliders. (O)
ar: float
    Approach rate of the map. (O/T/C/M)
cs: float
    Circle size of the map. (O/T/C/M)
hp: float
    Health drain rate of the map. (O/T/C/M)
od: float
    Overall difficulty of the map. (O/T/C/M)
bpm: float
    Beats per minute of the map. (O/T/C/M)
nCircles: Optional[int]
    The amount of circles in the map. (O/T/M)
nSliders: Optional[int]
    The amount of sliders in the map. (O/T/M)
nSpinners: Optional[int]
    The amount of spinners in the map. (O/T/C)
maxCombo: Optional[int]
    The max combo of the map. (O/T/C)

Installing rosu-pp-py

Installing rosu-pp-py requires a supported version of Python and Rust.

Once Python and Rust and ready to go, you can install the project with pip:

$ pip install rosu-pp-py

or

$ pip install https://github.com/MaxOhn/rosu-pp-py

Learn More

• rosu-pp documentation
• Rust documentation.
• PyO3 documentation.
• Python documentation.