Reviewed-on: #6
Simian
Simian is a small Raylib + AngelScript test project, refactored to be easy to extend and to show a safe hot-reload workflow for AngelScript.
This README was updated to reflect the current layout, build paths, and the small CMake wrapper approach used to optionally build ImGui / rlImGui when those folders are present.
What changed
- The original single-file demo was split into modules: Application, ScriptEngine, ScriptBindings and HotReload.
- Hot-reloads are performed safely: scripts compile into a temporary module first and only replace the running module on successful compilation. Compilation errors will no longer crash the running app.
- CMake wrappers live in
cmake/to build third-party projects that don't ship a CMakeLists.txt (example: ImGui, rlImGui). This keeps submodules untouched. - A
Justfilewas added with convenient recipes for configure, build, run and cleaning.
Quick start (Windows)
Open a developer prompt for Visual Studio or use PowerShell / cmd configured for MSVC.
Clone with submodules:
git clone --recurse-submodules <repo-url>
cd Simian
Using the included Justfile (optional):
# from project root
just configure # runs cmake -S . -B build -G "Visual Studio 17 2022" -A x64
just build # builds Debug by default (uses cmake --build)
just run # runs the built executable (Debug)
Or use raw CMake commands:
mkdir build; cd build
cmake -G "Visual Studio 17 2022" -A x64 ..
cmake --build . --config Release
# run:
build\Release\simian.exe
If you are using cmd.exe, the same commands apply (adjust quotes for generator if needed).
Linux / Unix
git clone --recurse-submodules <repo-url>
cd Simian
mkdir build && cd build
cmake -G "Unix Makefiles" ..
cmake --build .
./simian
Project layout (important files)
Simian/
├─ CMakeLists.txt # top level CMake
├─ Justfile # convenience tasks (configure/build/run/clean)
├─ include/ # public headers (Application, ScriptEngine, ScriptBindings, HotReload)
├─ src/ # implementation
├─ scripts/ # AngelScript source files loaded at runtime
├─ external/ # git submodules (raylib, angelscript, optional imgui/rlImGui)
└─ cmake/ # local CMake wrappers (imgui, rlImGui)
Hot-reload notes
- The app watches
scripts/for changes. When a script is updated it is compiled into a temporary AngelScript module. - If compilation succeeds, the temp module replaces the live
mainmodule and new functions are used. If compilation fails, the running module is left intact and a single-line error is shown on-screen. - This avoids crashes that happen when a script with compilation errors would otherwise replace/break function pointers while the engine is executing.
ImGui / rlImGui (optional)
The repository prefers to keep upstream code as submodules. Some upstream projects (like certain ImGui tags or rlImGui) don't provide a CMakeLists.txt. To support those without editing submodules, the project includes small wrappers in cmake/:
cmake/imgui/builds ImGui core (and optionally backends) whenexternal/imguiis present.cmake/rlImGui/builds the rlImGui integration and links it to theimguitarget if available.
If you prefer to use the upstream CMake (when present), the top-level CMakeLists.txt will prefer external/rlImGui's CMake if it detects one; otherwise it falls back to the wrapper.
To add ImGui/rlImGui as submodules:
# from repo root
git submodule add https://github.com/ocornut/imgui.git external/imgui
git submodule add https://github.com/NeoSpark314/rlImGui.git external/rlImGui
git submodule update --init --recursive
Then re-run CMake from a clean build directory.
Troubleshooting: if Git warns about "embedded git repository" when adding files, convert the folder to a submodule (remove cached tracked files, then add as submodule) — this README intentionally avoids modifying submodule contents.
Tests / Verification
Quick smoke test after building:
# run the Debug build
build\Debug\simian.exe
You should see the Raylib window. The running console prints from script when the default script executes (e.g. "[Script] Hello from AngelScript!").
If a script has a compilation error, the app will continue running and a brief error message is presented on the top-left of the window.
Updating submodules
Keep submodules pinned for reproducible builds. To update them safely:
cd external/raylib && git fetch && git checkout <commit-or-branch>
cd ../angelscript && git fetch && git checkout <commit-or-branch>
cd ../.. && git add external/raylib external/angelscript && git commit -m "Update submodules"
Notes
- The project was developed and tested on Windows with Visual Studio; Linux builds are supported but may need X11 / audio dev packages installed depending on your environment.
- The codebase avoids changing tracked submodule contents; use the
cmake/wrappers when a submodule doesn't include a CMake build.
License
- Raylib: Zlib License (see https://github.com/raysan5/raylib#license)
- AngelScript: MIT License (see https://github.com/angelcode/angelscript/blob/master/license.txt)
- Simian: Not open source (yet)