Scenes

Scenes are the unit the game switches between — logo splash, menu, gameplay, pause overlay, etc. engine::SceneManager (src/engine/scene_manager.{h,cpp}) holds a stack and routes the per-frame hooks; scenes call back via Manager()->Switch<T>() / Push<T>() / Pop() to navigate.

Transitions are queued and applied at the top of Update(), so a scene can safely call Manager()->Switch<...>() from inside its own OnUpdate without invalidating this.

Operations

Render() walks the stack from the lowest opaque scene up, so an overlay (IsOverlay() == true) keeps the scene below visible.

Scenes shipped

PauseMenuScene is the only IsOverlay() == true scene right now — the gameplay underneath stays rendered so the dim panel reads as a true pause.

The shared placeholder chrome (centered title + bottom hint) lives in scenes::ui::DrawPlaceholderFrame (src/scenes/placeholder.{h,cpp}); the five “🔲 placeholder” scenes call into it. Delete placeholder.{h,cpp} once every placeholder has been replaced with real content.

Boot flow

There’s no LogoScene — the .exe launch path paints the logo directly:

1. InitWindow → GL context ready
2. Game::ShowSplashFrame paints assets/textures/jl.png to the backbuffer. The OS shows it immediately.
3. Heavy init runs (engine::LoadFonts(AsciiPlusCJK), ImGui context, layer attach) — the user keeps seeing the splash.
4. Main loop starts, GameLayer::OnAttach does scenes_.Switch<MainMenuScene>().

This sidesteps the 1-2 s “frozen window” feel that the CJK font atlas bake would otherwise produce.

Quitting

A scene asks to terminate via Manager()->RequestQuit(), which sets a flag. Game::Run polls it after each Tick:

while (!WindowShouldClose() && !game_layer_->QuitRequested()) {
  Tick();
}
Shutdown();

The flag is honoured at a frame boundary, so Shutdown() always runs on the clean teardown path (font atlas freed, window.state saved, GL context closed in order). Scenes never call exit() or CloseWindow() themselves.