OpenEmperor

A clean-room reimplementation of Emperor: Rise of the Middle Kingdom for native macOS on Apple Silicon. 0.1.0-alpha.2 includes a playable city sandbox and an optional original-economy experiment. Gameplay and visual parity remain incomplete; original campaigns and savegames are unsupported.

You need your own installed or extracted Emperor game data. Original assets are read directly and are never bundled.

Build and run

Install Xcode Command Line Tools, CMake and OpenSSL 3. CMake fetches pinned SDL3 and JSON dependencies when needed and uses system zlib.

cmake -S . -B build -DCMAKE_BUILD_TYPE=Release -DCMAKE_OSX_ARCHITECTURES=arm64
cmake --build build --parallel
./build/openemperor

On first launch, select the Emperor data directory, then New Sandbox, a supported map and a rules profile. Existing saves retain their rules.

For the optional original economy, choose O Original economy, Cities/Xia.map, Normal and Paid four-house starter. Start the sandbox and press Space to run it. The player guide covers production, house development, saving and the remaining limitations.

Controls

• Space pauses or resumes; . advances one paused tick.
• Arrow keys pan; the mouse wheel zooms; Z cycles 1×/2×/4×.
• F5 / F9 save and load; Escape returns to the menu.
• Help lists the current profile's tools and shortcuts.

Saves and settings normally live in ~/Library/Application Support/OpenEmperor/OpenEmperor/ on macOS.

See known issues for current limitations and documentation for gameplay, development, testing and packaging.