Components

This page lists every project and engine namespace of MicroEngine with its responsibility and its dependencies, and then traces what calls what during a run. Use it to find where a change belongs: the core, the backend, a game, or the browser host.

Projects

Project	Kind	Responsibility	References
src/MicroEngine	Library	Backend-independent core: loop, scenes, input, graphics model, world, audio synthesis, UI, saves, achievements, headless platform	Nothing outside the .NET base library
src/MicroEngine.Sdl	Library	SDL 3 backend (SdlPlatform, SdlAudioDevice): the default on Windows, Linux, macOS, Android and iOS	MicroEngine, NuGet ppy.SDL3-CS, NVorbis
src/MicroEngine.Raylib	Library	raylib backend (RaylibPlatform, RaylibAudioDevice), a raylib-only DesktopLauncher, BrowserLauncher, BrowserSaveStorage	MicroEngine, NuGet Raylib-cs 8.1.0
src/MicroEngine.Desktop	Library	DesktopLauncher with the official desktop catalog (sdl, raylib, sdl-software, headless)	MicroEngine.Sdl, MicroEngine.Raylib
games/MeadowRun, games/CourtyardKey, games/TrailDuel, games/NeonRift	Executable	One complete game each: rules, scenes, art, audio, content	MicroEngine.Desktop
samples/HelloEngine	Executable	Minimal example game	MicroEngine.Desktop
tests/MicroEngine.Tests	MSTest	Engine contracts	MicroEngine
tests/MicroEngine.Desktop.Tests	MSTest (native)	SDL and raylib draw the same frames; replacing audio; platform errors	MicroEngine.Desktop
tests/<Game>.Tests	MSTest	Game rules, headless playthroughs, content checks	The game project
web/Host (MicroEngine.Web.csproj)	WebAssembly executable, built by internal tooling	The page bridge (WebHost) and page files; builds one selected game per package	The selected game project, and through it the desktop platforms; it runs on MicroEngine.Raylib
experiments/web/RaylibProbe	Experiment, outside the build	WEB-0 feasibility record	—

The core references no backend library. Games reference only MicroEngine.Desktop, which brings the backends and the core with it. The phone hosts in platforms/ are outside the solution.

Core namespaces

Namespace	Folder	Responsibility	Main types
MicroEngine	Math/	Value types and maths helpers	Color, RectF, MathX, Ease
MicroEngine.Core	Core/	Game lifecycle, the loop, platform boundary, runs and scripts, saves, content files, achievements	Game, GameSettings, IPlatform, GameRunner, GameLoop, GameSession, RunOptions, InputScript, HeadlessPlatform, SaveStore, ISaveStorage, FileSaveStorage, ContentFolder, Achievement, AchievementTracker
MicroEngine.Scenes	Scenes/	The scene stack, transitions, per-scene coroutines and tweens	Scene, SceneManager, Transition, CoroutineRunner, Tweener
MicroEngine.Input	Input/	Device state and named actions	Key, PadButton, IInputSource, InputMap
MicroEngine.Graphics	Graphics/	CPU images, procedural art, PNG decoding, sprites, animation, camera, parallax, particles, lighting, font, drawing interfaces	PixelImage, Art, SpriteAtlasBuilder, SpriteAtlas, Sprite, Animator, Camera2D, ParallaxLayer, ParticleSystem, LightMap, BitmapFont, IRenderer, IGraphicsDevice, Texture
MicroEngine.World	World/	Tile maps, swept collision, autotiling, entities	TileLayer, TileGrid, TileMotion, Autotile, TileRenderer, Entity, EntityList<T>
MicroEngine.Audio	Audio/	PCM clips and WAV decoding, the device interface, mixing, synthesis, sequenced music	AudioClip, IAudioDevice, SilentAudioDevice, AudioMixer, Synth, Song
MicroEngine.UI	UI/	Text boxes, menus, themes, achievement banners and list	Typewriter, DialogueBox, SelectionList, UiTheme, AchievementToasts, AchievementsScene

The manual covers each area: lifecycle, scenes, rendering, input, audio, assets, UI, persistence, achievements, backends.

Backend types

Type	Responsibility
RaylibPlatform	IPlatform over raylib: window, scaled and letterboxed canvas, renderer, texture creation, keyboard and gamepad, captures, F11 and Alt+Enter fullscreen on desktop. In a browser it leaves fullscreen and minimum size to the page
RaylibAudioDevice	IAudioDevice over raylib audio, including streamed OGG/MP3 music
SdlPlatform	IPlatform over SDL 3: window (full screen on phones), SDL renderer into a virtual-size texture, keyboard, gamepad, touch controls, lifecycle events, captures; CreateProfile(renderer) fixes a render driver
SdlAudioDevice	IAudioDevice over SDL audio streams; WAV and OGG (NVorbis) music; usable with another platform
GameLauncher (core)	Parses launcher flags, builds RunOptions and a PlatformRequest, resolves a profile from a PlatformCatalog, calls GameRunner.Run, returns an exit code
DesktopLauncher	GameLauncher with the official desktop catalog (in MicroEngine.Desktop) or with raylib only (in MicroEngine.Raylib)
BrowserLauncher	Sets SaveStore.DefaultStorage to BrowserSaveStorage and returns a GameSession that creates a RaylibPlatform per run
BrowserSaveStorage	ISaveStorage over localStorage, keys microengine/<Game>/<slot>

What calls what

Desktop

flowchart TB
  accTitle: Desktop launch
  accDescr: Program.cs calls DesktopLauncher.Run, which parses the arguments into RunOptions, resolves a platform profile from the catalog, creates the platform and calls GameRunner.Run.
  program["Program.cs"] --> launcher["DesktopLauncher.Run(game, args) <br/> → GameLauncher.Run"]
  launcher --> parse["LaunchArguments.Parse"] --> options["RunOptions <br/> (script, captures, <br/> seed, limits, mute)"]
  launcher --> platform["catalog.Resolve(--platform) <br/> .Create(PlatformRequest) <br/> (SDL, raylib or headless)"]
  launcher --> runner["GameRunner.Run( <br/> game, platform, options)"]

flowchart TB
  accTitle: Desktop game loop
  accDescr: GameRunner.Run drives the GameLoop: Start loads the game and pushes the first scene; each Tick runs the fixed steps and then draws the frame; Finish unloads the game.
  runner["GameRunner.Run(game, platform, options)"] --> loop
  subgraph loop["GameLoop"]
    direction TB
    subgraph start["Start"]
      direction LR
      load["Game.Load"] --> push["Scenes.Push(first scene)"]
    end
    subgraph tick["Tick (repeat)"]
      direction LR
      subgraph step["per fixed step"]
        direction TB
        apply["InputScript.Apply"] --> sample["InputMap.Sample"] --> update["Scenes.Update"] --> mixer["AudioMixer.Update"] --> flush["achievement <br/> banners and flush"]
      end
      subgraph frame["once per frame"]
        direction TB
        clear["Clear"] --> draw["Scenes.Draw"] --> banners["banners"] --> capture["capture"]
      end
      step --> frame
    end
    subgraph finish["Finish"]
      unload["Game.Unload, <br/> achievements flushed"]
    end
    start --> tick --> finish
  end

Browser

flowchart TB
  accTitle: Browser call flow
  accDescr: main.js calls WebHost, which uses a GameSession from BrowserLauncher.CreateSession; the session starts, ticks and ends the game loop.
  main["main.js"] --> host["WebHost.Start/Frame/Outcome/Stop <br/> (web/Host/Program.cs, [JSExport])"]
  host --> session["GameSession from <br/> BrowserLauncher.CreateSession(GameEntry.Create)"]
  session --> start["Start"] --> create["new game + <br/> new RaylibPlatform"] --> loopStart["GameLoop.Start"]
  session --> tick["Tick"] --> loopTick["GameLoop.Tick <br/> (one per <br/> requestAnimationFrame)"]
  session --> stop["end"] --> finish["GameLoop.Finish"] --> disposed["platform disposed"]

GameEntry is generated at build time from the game’s entry in the browser build configuration, so the browser builds the game with the same constructor expression as its desktop Program.cs.

Tests

flowchart TB
  accTitle: Test call flow
  accDescr: A test creates the game, initializes it with a HeadlessPlatform and steps it, or runs it with GameRunner.Run.
  test["test"] --> create["new MyGame(tempDir)"] --> init["game.InitializeForTest( <br/> new HeadlessPlatform())"] --> step["game.StepForTest() <br/> (InputMap.Sample + one fixed step)"]
  test -- or --> run["GameRunner.Run(game, <br/> new HeadlessPlatform(), <br/> new RunOptions { <br/> Script = ... })"]

Where a change belongs

Change	Place
A rule specific to one genre or game	games/<Name>
Something genre-neutral, or needed by two games	src/MicroEngine (with tests in tests/MicroEngine.Tests)
Anything that touches raylib or the browser	src/MicroEngine.Raylib or web/
A new windowing or audio library	A new IPlatform implementation; no game changes
A significant architectural change	Also a recorded design decision