`src/Main.cpp`

With Lysa Nodes the Application class only needs the render() call and the main loop.

Constructor

Application():
    lysa(contextConfiguration),
    scene(std::make_unique<RotatingAssetScene>(window)) {
 
    if (!lysa::ctx().fs.directoryExists("app://shaders")) {
        lysa::Log::critical(
            "'shaders' directory not found – run the application from the "
            "project root or build the 'shaders' CMake target first.");
        return;
    }
}

RotatingAssetScene(window) wires everything: it adds all nodes, calls attach(window), and subscribes to engine events. After the constructor returns the scene is fully operational; the application needs no further setup.

Shaders directory validation happens in the constructor rather than run() to surface the error before the main loop starts.

`run()`

void Application::run() {
    lysa::ctx().events.subscribe(
        lysa::MainLoopEvent::PROCESS,
        [&](const lysa::Event&) {
            window.getRenderTarget().render();
        });
 
    lysa.run();
}

A single subscription calls render() after the scene tree has processed the frame. Event subscriptions fire in registration order (FIFO); because RotatingAssetScene::attach(window) was called during construction — before Application::run() — the scene's PROCESS handler is always invoked first.

Lifetime and destruction

After lysa::Lysa::run() returns (when lysa::ctx().exit is set to true by MainWindow on CLOSING), the Application destructor releases objects in reverse declaration order: scene, then window, then lysa. This ensures that GPU resources owned by the scene are released before the device is destroyed.

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