CelestialGDX

An esoteric fork of LibGDX to cut down on stuff and improve maintainability.

This fork is completely undocumented, untested outside of my specific usecase, breaks ABI in more ways than I can count, and doesn't follow the upstream code style. Please don't use it.

Changes

• Nuke everything except desktop LWJGL3 backend
• Remove tests
• LOTS of code cleanup
• Update to Java 21
• Lwjgl3Application addLifecycleListener/removeLifecycleListener is no longer thread safe
• Many uses of reflection were removed
• Made some fields in Lwjgl3Application public for ease of use
• Lwjgl3Application's constructor is now protected
  • Use the static "create" method (or extend it) and pass an ApplicationCreator that makes an instance of your game listener
  • This is so your game can have final constants for the window, graphics etc
• Lwjgl3Application can no longer be created multiple times
• InputProcessor.scrolled now takes doubles and is no longer flipped
• FileHandle is now abstract and isn't bound to system files
  • FileType has been removed. Gdx.files methods will still work (except the FileType one), but they now return instances of SystemFileHandle or ClasspathFileHandle
  • WritableFileHandle is another abstraction that contains a write() method
  • GdxRuntimeException has been replaced with throws IOException
• Window icons now take Pixmaps instead of files
• Default HdpiMode is now Pixels
• AssetManager is no longer backed by nested maps
• AssetManager now gets the loader by class; per-file-extension loaders cannot be set anymore. This may change
• TEMP: 3D model loading by AssetManager will not work
• TEMP: Only Orthogonal tiled map rendering is supported right now
• GLFW events are now polled before rendering
• ApplicationListener.resize is no longer called on frame 1
• AssetManager loads assets in parallel now
  • Each asset is loaded on a virtual thread
  • Obtain a dependency by AssetLoadingContext.dependOn
  • If you need to do something on the main thread, use AssetLoadingContext.awaitMainThread
  • If you need to do CPU-bound work, use AssetLoadingContext.awaitWork to submit to a separate thread executor (and avoid blocking the carrier threads)
    • All asset loaders need to be rewritten for this!
• Tiled map loader has been mostly rewritten
  • Tiled maps no longer "own" resources (and thus aren't Disposable anymore), they are handled by asset dependencies now
  • Embedding textures into TMX files is no longer supported, you must have a separate TSX file
  • Tsx files are now their own asset, which TMX files will depend on. By default it looks for them in the same folder as the TMX, override this using the parameter
  • Object reference properties are no longer resolved, the property will now remain an int; you must resolve the object yourself later
  • You can now register custom types by TiledLoaderUtils.registerParser
  • Tiled maps made in 0.15 will no longer work (deprecated features removed)
  • MapLayer no longer contains object, its now only in ObjectLayer
  • MapObject is now abstract
  • Custom object types can now be registered by MapObject
  • TiledProjectLoader, TmxMapLoader and TsxTilesetLoader are now available by default in AssetManager
  • com.badlogic.gdx.maps.tiled -> com.badlogic.gdx.maps, since only tiled maps are supported now
  • convertObjectToTileSpace now defaults to true
  • Object immutable properties (like name, type, id and optionally tile) are now in an ObjectProfile record
  • Object list has been removed from MapLayer, it is now its own ObjectLayer class
  • Tile rotation is no longer read from objects with a gid
  • Objects are no longer rendered. It is up to your game to interpret them
  • Tilemap renderers now only render one layer at a time instead of going through all layers in the map. This is to allow games to render things like entities in between layers
  • Tilemap renderers can no longer own batches nor start/end them for you. You must do this yourself now
  • Renamed:
    • AnimatedTiledMapTile -> AnimatedMapTile
    • StaticTiledMapTile -> StaticMapTile
    • TiledMapTileLayer -> TileLayer
    • The "Map" was removed in object class names (i.e. PointMapObject -> PointObject)
    • The "Tiled" in renderer was changed to "Tile" (TiledRenderer -> TileRenderer)
    • Probably more, I lost track
• AssetManager's default log level is now ERROR instead of NONE
• The default SpriteBatch shader is no longer LOWP and no longer uses deprecated GLSL features
• The layout attribute a_texCoord0 was renamed to a_texCoord
• List has been renamed to UiList to prevent conflicts
• Only GL 3.2 is supported now. This is also the default

Removed

• SynchronousLoader / AsynchronousLoader
• FileHandle:
  • file, type, listFiles, exists, isDirectory, lastModified
  • all write-related methods
• FileHandleStream
• "Managed" resources, since Application is now singleton
• FileType
• Lwjgl3Window doesn't handle sync callbacks anymore, post to Lwjgl3Application instead
• Box2D / Bullet
• Multi-window support from LWJGL backend and subsequently a ton of syncrhonization code
• Automated tests
• Non-continuous rendering (along with ApplicationListener/LifecycleListener's pause and resume)
• ApplicationListener.create - do stuff in your constructor instead
• glfw_async, on Mac, you must call with -XstartOnFirstThread
• LwjglCanvas
• The entire reflection util package
• gdx-tools - use upstream
• ReflectionPoAol
• LWJGL initialBackgroundColor
• Audio - use gdx-miniaudio instead
• Netcode - use stdlib instead
• Preferences - use your own solution
• InputEventQueue - it calls InputProcessor instantly now
• Keys.ANY_KEY
• These methods in InputProcessor / Input:
  • touchDragged, getTextInput, vibrate, setKeyboardHeightObserver, isPeripheralAvailable, getRotation, getNativeOrientation, getDeltaX, getDeltaY, resetPollingStates
• FirstPersonCameraController / CameraController
• TextInputWrapper
• GestureDetector
• ActorGestureListener
• ScrollPane flickScroll
• AtlasTmxMapLoader, use a custom ImageResolver in the parameter instead
• SpriteBatch.maxSpritesInBatch
• TMJ map loading support. export to TMX instead
• tide map loading support, because tide is abandoned. use tiled instead
• MapLayers, use a List
• MapObjects, use a List
• Map, use TiledMap
• MapRenderer interface
• OrthoCachedTileMapRenderer
• Base64-related classes
• Nullability annotations - use jetbrains annotations instead
• AssetDescriptor.file
• GLDebugMessageSeverity and related methods
• SharedLibraryLoader - use LWJGL Platform.get()
• Seamless cubemaps, since it's not supported by GLES
• ANGLE GL2 backend
• GL profiling classes

Notes

• For gdx-controllers, bypass Controllers and create JamepadControllerManager directly instead
• The Gdx class remains for compatibility, but please don't use them - mutable static constants are questionable for maintainability. Use the function constructor in Lwjgl3Application and get the window to initialize your constants
• GDX GL classes are deprecated. Use GL classes from GLFW instead ()

TODO maybe

• rewrite Sync (fps cap) implementation
• possibly remove 3D
• remove use of deprecated code
• remove reflection entirely
• remove Json class (it is a MESS) in favor of Jankson
• unspaghetify TextureAtlas
• remove more useless stdlib replication classes
• make TextureRegion and its subclasses immutable
• try CachedThreadPool instead of virtual threads for asset loader
• optimize tiled renderer by turning the entire layer into one mesh
• support angle with GLES3
• finish replacing internal code to directly use LWJGL and remove all libgdx GL classes

This isn't a full code cleanup because I want to make my game. I'm only modifying stuff that affects me.

Setup

Gradle (Kotlin)

maven {
	name = "teamcelestial"
	url = "https://maven.teamcelestial.org/public"
}

configurations.all {
    // celestialgdx bundles the LWJGL backend
    exclude(group = "com.badlogicgames.gdx", module = "gdx-backend-lwjgl3")
    
    val version = "1.0.0-SNAPSHOT"
	// if using version catalogue:
	// val version = libs.versions.celestialgdx.get()
    
	resolutionStrategy.dependencySubstitution {
		fun sub(artifact: String) = substitute(
			module("com.badlogicgames.gdx:$artifact")
		).using(
			module("me.thosea.celestialgdx:$artifact:$version")
		).because("fork")

		sub("gdx")
		sub("gdx-freetype")
    }
}

Gradle (Groovy)

maven {
    name "teamcelestial"
    url "https://maven.teamcelestial.org/public"
}

configurations.all {
    val version = "1.0.0-SNAPSHOT"

    // celestialgdx bundles the LWJGL backend
    exclude(group: "com.badlogicgames.gdx", module: "gdx-backend-lwjgl3")

    resolutionStrategy.dependencySubstitution {
        def sub = { String artifact ->
            substitute module("com.badlogicgames.gdx:$artifact") using module("me.thosea.celestialgdx:$artifact:$version") because "fork"
        }
        sub("gdx")
        sub("gdx-freetype")
    }
}

Currently, the version is 1.0.0-SNAPSHOT.