Web package (--with-web-ci)

Generate a project with a web/Emscripten pipeline aimed at browser game development:

cppboot -n mygame --with-web-ci

The generated project builds its C++ library to WebAssembly, ships an HTML5 canvas demo structured like a game (an emscripten_set_main_loop loop driven by requestAnimationFrame, simulation separated from rendering, real delta time), and runs browser tests in headless Chrome on CI.

What gets generated

mygame/
  src/web/
    CMakeLists.txt   # canvas demo target (Emscripten only) + game-dev hooks
    main_web.cpp     # game loop: Update(dt) + EM_JS canvas renderer + HUD
    shell.html       # fullscreen-canvas shell page (--shell-file)
  tests/web/
    CMakeLists.txt   # GoogleTest compiled to wasm, SUFFIX .html, --emrun
    web_test.cpp     # version + JS-interop checks, run inside a real browser
  .github/workflows/web.yml

The root CMakeLists.txt gains Emscripten-aware guards: optional dependencies default off, the CLI demo app and benchmarks are hard-disabled for browser builds (the canvas demo replaces them), the core library is always built static, and tests/ switches to the browser test page under Emscripten. A new <MACRO>_BUILD_WEB_DEMO option (default on for top-level builds) controls the demo so library consumers don’t build it.

Game-development defaults

The demo target links with:

• -sALLOW_MEMORY_GROWTH=1 — no fixed heap ceiling
• -sUSE_WEBGL2=1 — WebGL2 context available when you graduate from canvas-2D
• --shell-file src/web/shell.html — a dark, fullscreen, DPI-aware canvas page you own completely (no Emscripten branding)

Commented, ready-to-enable hooks in src/web/CMakeLists.txt:

• Assets: --preload-file assets@/assets bundles a directory into the virtual filesystem — read with ordinary std::ifstream("/assets/...").
• SDL2: -sUSE_SDL=2 on both compile and link options for input, audio, and textures.

main_web.cpp shows the intended structure: keep per-frame simulation in Update(GameState&, double dt), render at the end of the frame, and never block the main thread — the browser owns pacing.

Requirements

Context	Needs
Generating the project	nothing extra
Building locally	an activated Emscripten SDK (emcmake, emcc on PATH) + Ninja
Running tests locally	Chrome (emrun drives it headless)
CI	nothing — ubuntu-latest + mymindstorm/setup-emsdk

Build and run

emcmake cmake -S . -B build/web-release -G Ninja -DCMAKE_BUILD_TYPE=Release
cmake --build build/web-release --parallel
emrun build/web-release/bin/mygame.html     # serves locally and opens the demo

Browser tests (GoogleTest compiled to wasm; exit code propagates through --emrun):

emrun --browser=google-chrome \
  --browser_args="--headless=new --no-sandbox --disable-gpu" \
  --kill_exit --timeout 120 build/web-release/bin/mygame_web_test.html

CI and releases

.github/workflows/web.yml runs on pull requests and pushes to the default branch:

1. Configure/build Debug and Release with emcmake (tests on).
2. Run the browser tests in headless Chrome for both configurations.
3. Verify the canvas demo (mygame.html/.js/.wasm) was produced.
4. Package mygame-web-wasm32-release-<version>.zip: the installed wasm32 static library + headers (consumable via find_package from any Emscripten CMake build), the playable demo under demo/, the pinned EMSCRIPTEN_VERSION, and the LICENSE.

The Release workflow gains a build-web job with the same build/test/package steps; on a v* tag or manual dispatch the zip is attached to the GitHub Release next to the desktop zips (and the Android AAR / iOS XCFramework when those flags are enabled).

Publishing the demo: the demo/ directory in the package is a static site — drop it on GitHub Pages, itch.io, or any static host. Serve over HTTP (wasm does not load from file://).

Limitations

• --with-web-ci cannot be combined with --with-modules (C++20 module scanning is untested with the Emscripten toolchain, and the package ships the classic header tree).
• --shared is honored on desktop platforms only; the web build always produces a static wasm library.
• The Emscripten SDK version floats (setup-emsdk with latest); the release package records the exact EMSCRIPTEN_VERSION used.

Android (--with-android-ci) and iOS (--with-ios-ci) complete the platform set.