Gecko - Fallout 2 map editor

Gecko is a modern cross-platform Fallout 2 map editor.

Screenshot

Building from source

This repository contains dependencies as git submodules. When you clone the repository make sure to use the --recursive flag or once cloned download submodules with git submodule update --init --recursive

Important: Use Release build for performance - Debug builds are significantly slower for map loading.

Dependencies

Qt6 (Core, Widgets, Svg) - Primary UI framework
SFML 3+ - 2D graphics rendering
spdlog - Logging framework
vfspp - Virtual file system for game archives
ZLIB - Compression support

Linux

# Install dependencies (Ubuntu/Debian)
sudo apt install qtbase6-dev qtbase6-dev-tools libsfml-dev libspdlog-dev

# Enter the cloned git repo folder
cd geck-map-editor
mkdir build && cd build
cmake ..
make

Windows

The easiest way to build GECK on Windows is to use vcpkg for dependency management and the latest Visual Studio for compilation.

vcpkg.exe integrate install
vcpkg.exe install --triplet x64-windows sfml qt6

Now just open the project in Visual Studio (File > Open > CMake...) and then build it (Build > Build All).

macOS

Install dependencies using Homebrew:

brew install sfml qt6 spdlog

# Set CMAKE_PREFIX_PATH to Qt6 installation
export CMAKE_PREFIX_PATH="/opt/homebrew/opt/qt6:$CMAKE_PREFIX_PATH"

mkdir build && cd build
cmake ..
make

Usage

Setup

Copy master.dat and critter.dat from your Fallout 2 installation to the resources subdirectory (gecko.app/Contents/Resources on Mac)
(Optional) Extract data files using dat-unpacker with the --transform option to convert filenames to lowercase

Controls

Navigation

Arrow keys or Right-click + drag: Pan the view
Mouse wheel: Zoom in/out
Window resize: View automatically adjusts

Selection Modes

The editor supports multiple selection modes accessible via the toolbar:

ALL: Select any element type with intelligent cycling
- Priority: Roof Tiles → Objects → Floor Tiles
- Cycling: Click same position repeatedly to cycle through available elements
OBJECTS: Select only objects
ROOF_TILES: Select only roof tiles
FLOOR_TILES: Select only floor tiles

Selection Controls

Left mouse click: Select element at cursor position
Multiple clicks on same position: Cycle through overlapping elements (in ALL mode)
Right mouse click: Clear all selections

Multi-Selection

Click and Drag: Area selection (FLOOR_TILES, ROOF_TILES, or OBJECTS modes only)
Ctrl+Click: Toggle item selection (add if not selected, remove if selected)
Alt+Click (Option+Click on macOS): Add item to existing selection
Shift+Click: Range selection for tiles (select area between first selected tile and clicked position)
Ctrl+A: Select all items of current selection mode type
Ctrl+D: Deselect all items

Object Manipulation

R key or Ctrl+R: Rotate selected object(s) - works with single or multiple selected objects

File Operations

Ctrl+N: Create new map
Ctrl+O: Open existing map
Ctrl+S: Save current map
Ctrl+Q: Quit application

Development

Code Formatting

./format.sh  # Formats all .cpp and .h files with clang-format

Testing

# From build directory
ctest
# Or run tests executable directly
./tests

Architecture Notes

Uses Qt6 for UI framework and SFML for 2D game rendering
Follows modern C++20 best practices with RAII and smart pointers
VFS integration allows reading from both loose files and DAT archives
All file paths use std::filesystem::path for cross-platform compatibility

Compatibility

The goal is to be compatible with vanilla Fallout 2, including loading maps created with the original Mapper.

Contributing

Contributions are welcome! Please ensure your code follows the project's coding standards and includes appropriate tests.

Credits

This project wouldn't be possible without the excellent work from:

Falltergeist - Fallout engine reimplementation
Klamath - Fallout file format library
FRM-Viewer - Fallout graphics format viewer
Dims Mapper - Legacy Fallout 2 map editor
darkfo - Web-based Fallout engine
Tabler icons

Gecko

Install / Use

README