🃏 Freecell

A live instance is running on gnikdroy.github.io/freecell

Freecell implementation in C. Play Freecell in a native build or in the browser (WebAssembly). This repo contains the game core, simple rendering/platform glue, and build rules using CMake + Ninja.

This implementation uses the same RNG as the original Microsoft FreeCell, so game deal numbers match the original implementation.

⚡ Quick summary

• Language: C
• Build system: CMake + Ninja
• Supported toolchains: Clang (native) and Emscripten (WASM) — only these two are tested.

✅ Requirements

• CMake (>= 3.15)
• Ninja
• Clang (native builds)
• Emscripten SDK (for web builds)
• Python (used by build generation steps, e.g., GLAD)

🛠️ Build instructions

1. Native (Clang + Ninja)

# create and enter build dir
mkdir build
cd build

# configure with Clang explicitly
cmake -G Ninja -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ..

# build the app and tests
cmake --build . --config Release --target freecell
cmake --build . --config Release --target tests

Result: executable(s) in build/ (e.g. build/Freecell.exe on Windows).

2. 🌐 Web (Emscripten / WASM)

mkdir embuild
cd embuild

# use emcmake to set the emscripten toolchain for CMake
emcmake cmake -G Ninja ..
cmake --build . --config Release --target freecell

Result: JS/WASM artifacts and Ninja manifest live in embuild/.

▶️ How to play

Basic Freecell rules (as implemented here):

• Layout: 8 tableau columns, 4 free cells, 4 foundation piles (one per suit).
• Objective: move all cards to the foundation piles, Ace → King in suit order.
• Moves:
  • Move the top card of any tableau column to a free cell, another tableau column, or a foundation (if it fits).
  • You may move a sequence of cards between tableau columns if there are enough empty free cells and/or empty tableau columns to perform the move (standard Freecell sequence-move rule).
  • Free cells hold one card each.
• Deal numbers: deals are reproducible and match the original Microsoft FreeCell numbering thanks to the identical RNG.

Controls: use the UI produced by the build (native or web). The UI offers dealing/new game and card interaction; exact controls depend on the build target (native window vs browser).

▶️ Running

• Native: run the produced binary, e.g.:

./build/Freecell.exe

• Web: open the generated HTML/JS from embuild/ in a browser (or serve the directory).

🧪 Tests

• Native tests: run build/tests.exe (or equivalent binary produced by the build).
• Web tests: see the Emscripten outputs in embuild/ (e.g. tests.js if generated).

🗂️ Project structure

• CMakeLists.txt — top-level CMake configuration and targets.
• src/ — source code
  • src/game/ — game logic
  • src/core/ — utilities and single-file third-party sources
  • src/rendering/, src/platform/ — rendering and platform glue
• include/ — public headers

🤝 Contributing

• Follow existing C style.
• Test both Clang native and Emscripten builds after changes.
• Open issues or PRs for bugs or feature requests.