Do I need the original game files to run OpenPREY?

Yes. The project does not include the original game's assets, so you need your own copy.

How is OpenPREY licensed?

project: GPLv3 (OpenPREY engine code); Human Head Studios: original Human Head Studios SDK EULA (Game library code in OpenPrey-GameLibs). The repository itself is the authoritative source.

Does OpenPREY include game assets?

No. You must own a legitimate copy of PREY (2006) to play.

OpenPREY

PortActive

An existing game or its source code brought to another platform.

Links, repository & details

About

OpenPREY is a free, open-source replacement engine for PREY (2006), built on Quake4Doom, that runs an existing copy of the game on Windows, Linux and macOS. It is under active development with an issues tracker. It does not include game assets, and a legitimate copy of PREY (2006) is required.

How it differs from the original

It adds controller play, widescreen and ultrawide support, HDR rendering, dynamic shadow maps and post-processing effects, and uses an SDL3-based window backend with several window modes and monitor selection.

Getting started

Install PREY (2006) from original media or another legitimate distribution, download the latest OpenPREY release for your platform, extract it and launch OpenPREY-client_x64. It usually finds the game install itself; if not, launch with +set fs_basepath pointing at the PREY folder. On Linux it currently runs through XWayland on Wayland desktops.

Known issues & limitations

The project is under active development and still has remaining issues.

What you need to run it

Original game files required. The project ships code only; you provide your own copy of the game (Windows, Linux, macOS version).

You must own a legitimate copy of PREY (2006); the project does not include game assets.
On Linux, the project currently runs through XWayland on Wayland desktops, and `DISPLAY` must be set.

Features

The project offers HDR rendering, dynamic shadow maps, and post-processing effects.
Supported window modes include windowed, borderless, desktop-native fullscreen, and exclusive fullscreen.
Aspect ratio and field of view are derived automatically from the current render size.

How to install

Get PREY (2006) from original media or another legitimate distribution; CD-era install layouts are supported.
Download the latest release archive for your platform from the Releases page.
Unpack the archive to any folder.
Windows players do not need to install extra software.

Summarised from the project's README.

Licensing & legal

The GPLv3 applies to the engine code only; the game library code is derived from the PREY SDK and falls under the Human Head Studios SDK EULA.

Additional notes

Build system: It is built with Meson and Ninja, with nightly builds for Windows, Linux and macOS from GitHub Actions.

FAQ

What is OpenPREY?: OpenPREY is an open-source port. An existing game or its source code brought to another platform. The original game ran on Windows, Linux and macOS.
Do I need the original game files to run OpenPREY?: Yes. The project does not include the original game's assets, so you need your own copy.
How is OpenPREY licensed?: project: GPLv3 (OpenPREY engine code); Human Head Studios: original Human Head Studios SDK EULA (Game library code in OpenPrey-GameLibs). The repository itself is the authoritative source.
Does OpenPREY include game assets?: No. You must own a legitimate copy of PREY (2006) to play.