PerformancePoints++

Calculate osu! difficulty and performance attributes for all four gamemodes in ISO C++98.

• All four gamemodes, with the mods each one supports.
• Ported from osu!lazer and verified against its 2026.730.0 release; the parser is from fosu de01f188f2be7831f619ca09882cf2f55b0c9720.
• Python bindings use the C ABI through generated ctypes code. One wheel per platform supports CPython 3.10 and newer.
• Node bindings use Node-API. One build works across supported Node.js versions.
• C# bindings use the same C ABI. One assembly works on .NET Framework 2.0 and modern .NET.

Install

The library is built and installed with CMake:

cmake -S . -B build
cmake --build build
cmake --install build

A consumer finds the package with find_package and links the target it needs:

find_package(pppp CONFIG REQUIRED)
target_link_libraries(your_target PRIVATE pppp::fosu)
pppp_place_engine(your_target)   # puts the SIMD engine next to your_target

Usage

#include <pppp/backend.h>
#include <pppp/beatmap.h>
#include <pppp/pppp.h>

pppp::Beatmap beatmap;
pppp::Status status = beatmap.load_file("map.osu");    // or beatmap.load_buffer(data, size)
if (!status.ok()) { puts(status.message()); return 1; }

// The parser engine the loader chose, read-only: pppp::EngineKind::SCALAR, AVX2 or NEON.
// e.g. `pppp::backend() == pppp::EngineKind::AVX2` on an x86-64 host.

pppp::Mods mods;
if (!mods.parse("HDDT").ok()) return 1;                 // "DT:speed_change=1.4" for settings
// pppp::Mods::from_legacy(pppp::mods::LEGACY_MOD_HIDDEN, beatmap.mode) for osu!stable's bitmask
// mods.push_back(pppp::mods::MOD_HD) for a single mod

pppp::DifficultyAttributes diff_attrs;
if (!pppp::Difficulty().mods(mods).calculate(beatmap, diff_attrs).ok()) return 1;
if (const pppp::OsuDifficultyAttributes* osu = diff_attrs.osu()) printf("aim %.2f\n", osu->aim_difficulty);

pppp::ScoreInfo score;
score.mods = mods;
score.statistics[pppp::HIT_RESULT_GREAT] = 600;
score.statistics[pppp::HIT_RESULT_OK] = 1;
score.max_combo = diff_attrs.max_combo(); score.accuracy = 0.9994;

pppp::PerformanceAttributes pp_attrs;
if (!pppp::Performance(beatmap, diff_attrs).score(score).calculate(pp_attrs).ok()) return 1;

printf("%.2f* %.2fpp\n", diff_attrs.star_rating(), pp_attrs.total());

Python

import pppp

beatmap = pppp.Beatmap.from_file("map.osu")

difficulty = pppp.Difficulty(mods="HD,DT").calculate(beatmap)
performance = pppp.Performance(mods="HD,DT", max_combo=789, accuracy=0.992, misses=2).calculate(beatmap, difficulty)

print(difficulty.star_rating, performance.total)

C#

using Pppp;

using (Beatmap beatmap = Beatmap.FromFile("map.osu")) {
    DifficultyAttributes difficulty = new Difficulty { Mods = "HD,DT" }.Calculate(beatmap);
    PerformanceAttributes performance =
        new Performance { Mods = "HD,DT", MaxCombo = 789, Accuracy = 0.992, Misses = 2 }.Calculate(beatmap, difficulty);

    Console.WriteLine(difficulty.StarRating + " " + performance.Total);
}

Node

import { Beatmap, Difficulty, Performance } from "@7mochi/pppp";

const beatmap = await Beatmap.fromFile("map.osu");

const difficulty = new Difficulty({ mods: "HD,DT" }).calculate(beatmap);
const performance = new Performance({ mods: "HD,DT", maxCombo: 789, accuracy: 0.992, misses: 2 }).calculate(beatmap, difficulty);

console.log(difficulty.starRating, performance.total);

Options

CMake option	Default	What it does
PPPP_WITH_FOSU	ON	the .osu parser and its adapter
PPPP_ISA	auto	parser engine: auto, scalar, avx2 or neon
PPPP_BUILD_TESTS	top-level only	the test suites (fetches doctest)
PPPP_BUILD_PYTHON	OFF	the native library the Python package loads
PPPP_BUILD_NODE	OFF	the Node-API extension module
PPPP_BUILD_CAPI	OFF	the C ABI shared library the C# bindings use
PPPP_WIN2K	OFF	the shim that keeps binaries loadable on Windows 2000
PPPP_INSTALL	top-level only	the find_package(pppp CONFIG) package
PPPP_WARNINGS_AS_ERRORS	OFF	-Werror on the library's warnings
PPPP_PGO	OFF	profile-guided optimization: GENERATE instruments, USE consumes the profile (make build-pgo runs both, training on the parity suites)
PPPP_PGO_DIR	<build>/../profile-data	where the profile is written and read (GCC keeps it beside each object)

Development

The toolchain comes from the flake:

nix develop        # cmake, ninja, gcc, clang, python, node, .NET and pre-commit
make test-auto     # build and run the suites
make check-format  # the C++ formatting, checked
make build-pgo     # a PGO Release build in build_pgo (GCC or Clang)

Formatting, the Python types and the file hygiene are also enforced by pre-commit. The dev shell installs the hooks when you enter it; to run them by hand:

pre-commit run --all-files

clang-format and nixfmt come from the dev shell; outside it the hooks fall back to nix develop.

AI Disclaimer

The port was done with AI assistance (DeepSeek V4.1 Flash and Opus 5), working file by file against ppy/osu. I have gone through most of the code to check that it's correct and to fix what isn't. Not all of it though, some files have not been checked yet and I'm still working through the rest. If you find something, an issue is welcome.

If you would rather not use something written with AI assistance, there are other options for the same problem:

• osu-native with my bindings: osu-native-py, osu-native-go and osu-native-jar.
• rosu-pp with rosu-pp-py, rosu-pp-ffi and rosu-pp-js.