OpenGromada

Reverse engineered engine that is used in variety of games developed by Sigma Games and some of 3rdparty games using this engine. Naming comes from the internal naming of the engine in registry code.

Features

• Supports AS1/ZS1, Theseus, Crazy Lunch, Locoland/Steamland.
• Cross-platform and cross-arch support
• Widescreen resolution support
• Gamepad support
• Bumped engine limits up to 8192. Use GETSPRITE_VID + nvid for the entire range

Building

Requirements:

• CMake/Premake
• C++20 compiler
• SDL3
• Steamworks SDK (optional, needed only for Steam's AS1)
• FFmpeg 6+ (optional, needed for Locoland videos)

cmake -S . -B build/native -DCMAKE_BUILD_TYPE=Release
cmake --build build/native --parallel

The single-configuration executable is build/native/OpenGromada on Unix-like systems or OpenGromada.exe on Windows.

Place the executable beside objects.res and the game's data directories. Alternatively, point to that directory with --data-path="/path/to/game".

Runtime options

Option	What it does
--renderer=auto|gpu|software	Selects actual game rendering. auto tries the GPU and falls back to software if initialization fails. gpu requires the GPU. software uses the CPU renderer.
--gpu-driver=vulkan|direct3d12|metal	Forces a graphics driver. Requires --renderer=gpu. Without this option SDL selects the driver.
--resolution=WIDTHxHEIGHT	Sets the resolution. --resolution=auto (alias: desktop) uses the desktop resolution. You can also give --width and --height.
--fullscreen / --windowed	Selects fullscreen or windowed mode. New profiles start in fullscreen at the desktop resolution. Automatic windowed mode fits the window inside 1280x800.
--native-resolution	The default. The game renders gameplay at the native resolution, inside a frame with a maximum size of 1280x720 (1152x720 on 16:10 screens). Menus always render at the full native resolution. On maps with small terrain, the game can select a smaller frame to hide unbuilt areas.
--no-native-resolution	Uses the profile's base height frame. The frame width follows the screen aspect.
--render-width=WIDTH	Limits the width of the render frame to WIDTH. If you also give --native-resolution, the native mode wins.
--ui-scale=auto|1|2|3	Sets the size of the HUD and menu art. auto selects a scale from the resolution, with a maximum of 2x during gameplay. Explicit values are exact.
--vsync / --no-vsync	Turns vertical sync on or off.
--red-blood	Shows the original red blood effects.
--data-path=PATH / --data-dir=PATH	Sets the folder that holds the game data.
--game=as1|zs1|theseus|crazy-lunch|locoland	Selects a title explicitly.
--probe-game=json	Prints detection, configuration, resource sections, candidates and runtime/movie availability, without starting the game.
--pref-path=PATH	Sets the folder for saves, settings, and logs.
--config=PATH	Selects the startup configuration before opening resources.
--script=PATH	Overrides the startup map/script. Directly starting a later campaign map can skip initialization performed by earlier maps.

File locations

Writable configuration, progress, saves, and logs use SDL's per-user preference directory. The default locations are:

• Linux: ${XDG_DATA_HOME:-$HOME/.local/share}/SigmaTeam/
• Windows: %APPDATA%\SigmaTeam\
• macOS: ~/Library/Application Support/SigmaTeam/

License

Sustainable Use License