SDL3CPlusPlus/README.md

SDL3CPlusPlus

A minimal SDL3 + Vulkan spinning cube demo.

Build

1. Dependencies

   • Install or update Conan 2.x.
   • Run:

     conan profile detect
     conan install . -of build -b missing -s compiler=msvc -s compiler.version=194 -s compiler.cppstd=17 -c tools.cmake.cmaketoolchain:generator="Visual Studio 17 2022"
     

     so Conan pulls in lua, SDL3, Vulkan, and the rest of the graph defined in conanfile.py.

2. Configure

   • Default (Visual Studio): cmake -B build -S .
     • This uses the Visual Studio 2022 generator.
   • Ninja (clang/MinGW): configure into a clean folder, e.g., cmake -G Ninja -B build-ninja -S .
     • CMake already appends C:\ProgramData\chocolatey\bin to CMAKE_PROGRAM_PATH, so Ninja and Chocolatey LLVM tools are discoverable without extra PATH edits.
     • Ninja is a single-config generator. When no multi-config generator has been used, the project defaults CMAKE_BUILD_TYPE=Release; override it with -DCMAKE_BUILD_TYPE=Debug if you need another configuration in that folder.
   • Ninja with MSVC: open a Developer Command Prompt (call "%VSINSTALLDIR%VC\\Auxiliary\\Build\\vcvarsall.bat" x64 or run that batch file from PowerShell) and configure with

     cmake -G Ninja -B build-ninja-msvc -S . -DCMAKE_BUILD_TYPE=Release
     

     Keep using the same prompt (so cl.exe carries the SDK/CRT paths) and build with cmake --build build-ninja-msvc --config Release.
     • Quick one-liner that initializes the MSVC environment and runs the Release build from a regular shell:

       cmd /c "call \"%VSINSTALLDIR%VC\Auxiliary\Build\vcvarsall.bat\" x64 && cmake --build build-ninja-msvc --config Release"
       

       When you run the command from PowerShell wrap the cmd invocation in single quotes so the embedded double quotes stay intact:

       cmd /c 'call "%VSINSTALLDIR%VC\Auxiliary\Build\vcvarsall.bat" x64 && cmake --build build-ninja-msvc --config Release'
       

   • Optional clang-tidy: add -DENABLE_CLANG_TIDY=ON
     • CMake searches both C:\Program Files\LLVM\bin and C:\ProgramData\chocolatey\bin, so standard LLVM/Chocolatey installs are found automatically.
     • The wrapped clang-tidy binary prints [clang-tidy] starting . and [clang-tidy] finished (exit .) markers so you can spot linting in verbose logs even when no diagnostics appear.

3. Build

   • cmake --build build --config Release --target sdl3_app (or point at build-ninja if you used Ninja).
   • Shaders land in build/shaders or build-ninja/shaders, so the executable can load cube.{vert,frag}.spv.

Run

cmake --build build --target spinning_cube
./build/spinning_cube

If you rely on the Conan runtime environment (some dependencies export env vars), source build/conanrun.sh on Linux/macOS or run build\\conanrun.bat on Windows before launching the binary.

Runtime configuration

1. main.cpp now uses a JSON-driven entrypoint.
   • Pass sdl3_app --json-file-in <path> to load runtime settings such as the Lua script path, window size, and lua_debug.
   • The loader enforces valid types and resolves relative scripts next to the configuration file.
2. Generate a starter JSON with the shipped script locations:

   sdl3_app --create-seed-json config/seed_runtime.json
   

   The helper assumes scripts/cube_logic.lua lives beside the executable and writes normalized paths.
3. Store or override the app-wide config with sdl3_app --set-default-json [path].
   • Windows uses %APPDATA%/sdl3cpp; other platforms use $XDG_CONFIG_HOME/sdl3cpp/default_runtime.json, falling back to ~/.config/sdl3cpp.
   • Providing a path duplicates that JSON into the platform default without editing the runtime values.
   • When the default file exists the executable reads it automatically; otherwise it falls back to the built-in script discovery logic.

GUI Demo

scripts/gui_demo.lua shows off the Lua GUI framework (buttons, text boxes, list views, and SVG icons) rendered on top of the Vulkan scene. Launch it with ./build/sdl3_app --json-file-in config/gui_runtime.json (or use that config via sdl3_app --set-default-json) to run the interactive overlay in the window.

Dependency automation

This project ships a renovate.json configuration so Renovate can open PRs that bump the Conan packages listed in conanfile.py. Either install Renovate locally (npm install -g renovate or npx renovate) and run it from the repo root, or enable the Renovate bot on your GitHub/GitLab install to pick up the configuration automatically.