JStarsReborn

JStarsReborn

An unofficial Windows x64 PC port runtime for J-Stars Victory VS+ (PS4, CUSA01593 version 01.02). It runs the original x86-64 game code from your own, already-decrypted dump natively, and replaces the console's system services, graphics (a shadPS4-derived Vulkan renderer), audio (WASAPI) and input (XInput and keyboard). A launcher, JStarsReborn.exe, checks and prepares the dump and starts the game.

No game files, keys, firmware or decryption tools are included or downloaded. The game folder is only ever read.

Legal: unofficial fan project, not affiliated with or endorsed by the game's publisher, developer or rights holders. Use only a dump you made yourself from a copy of the game you legally own. Piracy is not supported in any form. Provided as is, without warranty. Read the full DISCLAIMER.md.

State (0.5.1, pre-release): on the owner's Windows 11 PC the game boots, shows the title, creates and loads its own save data, and runs the menus and Free Battle matches, driven by scripted test input and by a live controller. Movies are skipped (no decoder) and trophies are an empty set. Whether it plays well and sounds right has not been confirmed by a human tester yet. See CHANGELOG.md for the full list of known issues.

Online play is still in testing. It is peer-to-peer (no server) and off by default: turn it on in the launcher's Online page. A host can open its ports with UPnP and share a room code; players on the same network or with the code see the host's Friendly Match room. Joining a room, and so an actual match between two players, does not work yet. Nothing contacts PlayStation Network and no account is used. See docs/ADR-007-online.md.

Using it (Windows)

1. Build the release (below), or use a release ZIP, and unzip it anywhere (paths with spaces are fine).
2. Start JStarsReborn.exe, choose your game folder (the one with eboot.bin, sce_sys and sce_module), press Play.
3. Close the game window to end a session. Settings, saves, prepared data and per-session logs live in %LOCALAPPDATA%\JStarsReborn.

Controls: an Xbox-compatible (XInput) controller, or the keyboard when no controller is connected (mapping in docs/INPUT.md and on the launcher's Controls page).

Layout

Path	What it is
src/launcher/	the launcher (Win32): pages, session tracking, diagnostic report, preparation front end
src/prepare/	native preparation: SELF/ELF parsing, relocation, import binding, linking libc.prx and libSceFios2.prx into one boot image
runtime/	the execution runtime (C): loader, kernel/OS replacements, file system, save data, audio, input, GPU host glue
gpu/	the vendored shadPS4 renderer (pinned revision, local patch in gpu/patches/, see gpu/VENDOR.md)
tools/	build and release scripts, the Python reference preparation tools, Windows verification runners, vkprobe
tests/	launcher core tests, scripted pad inputs for automated runs, older foundation tests
docs/	architecture decisions (ADR-005, ADR-006), import audit, input, build and release instructions
evidence/	logs and records of the runs on the owner's hardware that the change log refers to
src/app, src/core, src/setup, ...	the 0.2.x DX12 foundation and setup tool (JStarsFoundation target), kept for history

Building

The release is cross-compiled on Linux with mingw-w64 (GCC 13, posix threads) plus clang-18 for four renderer units: see docs/BUILD_RELEASE.md. In short:

cmake -S gpu -B build-gpu-win -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=$PWD/gpu/cmake/mingw-w64-x86_64.cmake
ninja -C build-gpu-win
tools/build_release.sh build-gpu-win/libjstars_gpu.a build/release

Checks that run on Linux: tools/prepare_native_check.sh (native preparation is byte-identical to the Python tools), the launcher core tests, and the runtime host self-test (runtime/jstars-boot --selftest-host).

A native Windows host-service test build is also available through tools/windows_build. Its verified 266-check result is from 656e15c; it is not the GPU game launcher. Linking the supplied GCC renderer with the installed llvm-mingw C++ libraries remains unresolved.

History

• 0.2.x: native DX12 foundation, setup tool and audit (PROJECT_AUDIT.md).
• 0.3.0 (build w): execution runtime plus Vulkan renderer; a whole scripted Free Battle on Windows hardware (docs/checkpoints/README-CHECKPOINT-0.3.0.md, evidence/windows-gpu-0.3.0/).
• 0.4.0: launcher, native preparation, normal play sessions, renderer storage-format fix (evidence/windows-launcher-0.4.0/).
• 0.5.0 (pre-release): online in testing: real sockets, local sign-in answers, Matching2/Signaling, room hosting and search; launcher online setting.

License

See also DISCLAIMER.md.

The runtime, renderer and launcher together are GPL-2.0-or-later (the vendored shadPS4 code is GPL-2.0-or-later); see THIRD_PARTY_NOTICES.md and licenses/. J-Stars Victory VS+ and its characters belong to their owners; this project is not affiliated with them.