PE2PC

PE2PC: Parasite Eve II, native on PC

A native PC port of Parasite Eve II (PlayStation, USA release) built on the decompilation by GabeRealB. The game's own code, decompiled to C, is compiled for the PC and runs natively; a small runtime written for this project stands in for the console (graphics, sound, CD, controllers, memory cards). No emulator and no code from Sony.

This repository contains no game data. To play, you need dumps of your own discs (SLUS-01042 and SLUS-01055, as .chd or .cue images). The port reads the game's data from them at run time.

Status

Playable on Windows: both discs, movies, music and sound, saves, controllers. It plays as the console does and adds what a PC can, all optional:

• Higher resolution, up to 8x the console's 320x240, rendered on the graphics card, with exact (sub-pixel) vertex positions so models neither wobble nor crack, and perspective-correct textures.
• Smooth motion at 60 fps: the game still runs at its 30, and frames in between are drawn with the 3D models halfway, with no added delay.
• Filtering: smoothed 3D textures (bilinear) and smoothly enlarged pre-rendered backgrounds (bicubic).
• Presentation: a CRT look (scanlines and aperture grille) and integer scaling.
• Modern movement: the stick points where to go, relative to the camera, in exploration and in battle; or the original tank controls with a quick turn (back + run).
• Sharp text: the dialogue, the menus, the loading captions and the disc change's lines drawn from high-definition fonts (the built-in DejaVu Sans Bold and Courier Prime) instead of the game's small pictures of text, at internal resolutions above the console's.
• Mods (experimental, turned on in Settings): replace the pre-rendered backgrounds and full-screen pictures and the textures with your own at any resolution, the music with recordings, the movies with video files, any of the game's files, and the dialogue with translations; cheats and memory patches; the game's pictures, textures, music, movies, files and dialogue extracted from your discs with pe2 --extract to make them (see docs/MODDING.md).
• Cheats (in pe2.toml, [cheats]): infinite HP or MP, one-hit kills, every hit critical, and EXP and BP multipliers.
• Comfort: a launcher worked by mouse, keyboard or controller (English or Portuguese), remappable keys and controller buttons, pause, screenshots, borderless full screen, and Discord showing where you are in the game, with your EXP and BP.

Memory cards are raw .mcd images, so saves move both ways with DuckStation.

How it was made

This port was developed with AI assistance: much of its code, tools and documentation was written with Claude Code (Anthropic). That is why it came together quickly.

Every step was directed and supervised by a person. Snaity set the goals and the rules the project keeps (no game data, no Sony code, the game's own behaviour as the reference), reviewed each change, played and tested it in the game, compared it with the console through DuckStation, and made every commit. Bugs were tracked down by measuring the running game, not by guesswork, and fixes went in only after they held up in play.

Playing

You need Windows 10 or 11 and a graphics card with Vulkan or OpenGL 3.3.

Take the latest release, or the last build of main (the nightly pre-release: untested beyond CI), or build it as docs/BUILDING.md explains; then start pe2.exe. The launcher's Setup asks for your disc images, memory cards and a quality level; after that, Play starts the game. Settings and Controls change everything later.

Default keys (Controls remaps them):

PlayStation	Keyboard	Controller
D-pad	Arrow keys	D-pad (or left stick)
Cross / Circle / Square / Triangle	Z / X / A / S	A / B / X / Y
L1 / R1 / L2 / R2	Q / W / E / R	LB / RB / LT / RT
Start / Select	Enter / Backspace	Start / Back

Key	Does
Alt+Enter	Borderless full screen on and off
P	Pause and resume
F9	Screenshot (in the data folder's screenshots/)
F10	Swap discs by hand (the game normally asks and it happens by itself)
Esc	Quit (asks first, unless turned off in Settings)

Where your files go

Settings (pe2.toml), the default memory cards, screenshots and the game's log live in the data folder: %APPDATA%\PE2PC on Windows (Settings has a button that opens it). For a portable setup, put an empty portable.txt next to pe2.exe and everything stays in its folder. pe2.example.toml documents every setting.

Layout

Path	Contents
decomp/	Submodule with the game's C code (fork of the decomp)
port/	C side: the PC's own Psy-Q headers and library routines, software GTE
crates/pe2-host/	Rust host: launcher, window, graphics, sound, CD and the rest of the runtime
tools/	Build, debugging, verification and release tools
snapshot/	What the build takes from the decomp's PSX build, without the game's data, to build without the discs
docs/	Architecture, building, modding and releasing

Golden rule

Never commit disc images, extracted files, includes generated from the disc, saves or screenshots. The pre-commit hook (python tools/install_hooks.py) runs tools/check_no_game_data.py and blocks them.

Credits

• Port: Snaity (Adriano Teodoro), developed with AI assistance (Claude Code, by Anthropic) under Snaity's direction and review (see How it was made).
• Launcher art (the background, the PE2PC logo and the icon): made with AI image generation under Snaity's direction; CC0 1.0 as the rest of the project.
• Decompilation: GabeRealB and its contributors. The port stands on their work.
• Parasite Eve II: Square, and everyone who made the original game.
• Hardware documentation: Martin Korth's psx-spx (Nocash PSX Specifications), which the runtime's GPU, SPU, GTE, MDEC and CD-ROM are written from.
• Sub-pixel precision: the idea of PGXP, by iCatButler.
• Fonts: DejaVu Sans Bold, built in for the dialogue and the menus (Bitstream Vera license with DejaVu's changes in the public domain), and Courier Prime for the loading captions and the disc change (SIL Open Font License 1.1); their licenses are in crates/pe2-host/res/fonts/.
• Reference: DuckStation, used to compare behaviour (none of its code is used).
• Libraries: wgpu, winit, egui/eframe, gilrs, cpal, chd-rs, iced-x86, rfd, ab_glyph (the fonts), discord-rich-presence, png, image-webp, toml, toml_edit, serde, pollster, windows-sys, lewton, claxon and hound (mods' music), openh264 with Cisco's OpenH264 (BSD-2-Clause, © Cisco Systems), mp4 and Symphonia (mods' movies), and the crates they build on. Thanks to all their authors.

Legal

Parasite Eve II is © Square (now Square Enix). This project is not affiliated with or endorsed by them, and includes none of the game's data: you supply your own copy.

The project's own code is dedicated to the public domain under CC0 1.0, as the decompilation in decomp/ is. The fonts in crates/pe2-host/res/fonts/ keep their own licenses, and so do the libraries pe2.exe is built from: each release carries their notices in THIRD-PARTY-NOTICES.txt (python tools/third_party.py writes them).