Preferences & save data

backend.ClientPrefs

A static class holding every user setting as a plain field. Options menus mutate the fields directly; gameplay reads them directly. There is no settings object to pass around.

A sample of what lives there (see the generated reference for the complete list):

Group	Fields
Gameplay	downScroll, middleScroll, opponentStrums, ghostTapping, noReset, complexAccuracy, noMarvJudge, ezSpam, antiCheatEnable, safeFrames
Visuals	noteSkin, splashType, noteSplashes, oppNoteSplashes, maxSplashLimit, oppNoteAlpha, hideHud, timeBarType, scoreStyle, healthBarStyle, iconBounceType, simplePopups
Feedback	hitsoundVolume, hitsoundType, missSoundEnabled, showNPS, showComboInfo, botWatermark
Performance	camZooms, showNotes, smoothHealth, comboStacking, enableColorShader, charsAndBG
System	showFPS, showRamUsage, showMaxRamUsage, debugInfo, autoPause, checkForUpdates, discordRPC, peOGCrash
Crossfades	crossFadeMode, crossFadeLimit, boyfriendCrossFadeLimit
Mobile	mobileCAlpha, mobileCEx

Persistence

Function	What it does
loadDefaultStuff()	snapshots the default keybinds into defaultKeys (called from Main.setupGame)
loadPrefs()	copies values out of FlxG.save.data into the static fields (called from InitState)
saveSettings()	reflects the fields back into FlxG.save.data and flushes

Both directions use Reflect over the class fields, with blacklists so derived or structural data is not round-tripped:

"saveBlackList" => ["keyBinds", "defaultKeys", "defaultArrowRGB", "defaultPixelRGB", "defaultQuantRGB"],
"loadBlackList" => ["keyBinds", "defaultKeys", "defaultArrowRGB", "defaultPixelRGB", "defaultQuantRGB"]

Keybinds are saved separately as save.data.customControls. Volume/mute keys are pushed back into TitleState.muteKeys / volumeDownKeys / volumeUpKeys after loading so Flixel picks them up.

Adding a setting

1. Add a public static var to ClientPrefs with a sensible default.
2. Add an Option to the right substate in options/ (see Options menu).
3. Read it where it matters. Nothing else is needed — save/load is reflective.
4. If the value affects timing or rendering globally, call the relevant recalculate*() (e.g. Conductor.recalculateTimings()) when it changes.

Where the save lives

InitState binds the save as:

FlxG.save.bind('funkin', CoolUtil.getSavePath());

CoolUtil.getSavePath() returns the company/app path used by Flixel's FlxSave (ninjamuffin99/Funkin-compatible on desktop so saves migrate from other engines). On Android/iOS — and, thanks to the FlxSave haxelib patch, on Flash/AIR — the save is a plain SharedObject instead of a sys-based file.

Keybinds

• ClientPrefs.keyBinds:Map<String, Array<FlxKey>> maps a control name to its keys.
• backend.Controls exposes the named actions gameplay and menus check (ACCEPT, BACK, NOTE_LEFT, …).
• backend.PlayerSettings sets up the input device(s) at boot.
• backend.InputFormatter turns a key into the label the controls menu shows.
• options.ControlsSubState is the rebinding UI.

Highscores

backend.Highscore stores per-song and per-week records (score, accuracy, misses, rating) in the same FlxG.save, keyed by formatted song name and difficulty. data.Song and states.FreeplayState read it to show the record on the song list.

Achievements

backend.Achievements (flag ACHIEVEMENTS_ALLOWED) holds the unlock table, also saved via FlxG.save. Achievements.load() runs during Main.setupGame(). objects.AchievementPopup shows the toast, states.AchievementsMenuState lists them, and mods can define their own in mods/<mod>/achievements/.

Script-visible save data

Scripts get an isolated namespace rather than access to FlxG.save: initSaveData, setDataFromSave, getDataFromSave and flushSaveData (see the Lua API reference).

These saves are keyed only by the name you pass to initSaveData (stored in PlayState.instance.modchartSaves, backed by FlxSave under CoolUtil.getSavePath()/<folder>, default folder psychenginemods). There is no per-mod namespacing: two mods that call initSaveData('save') share the same file and will overwrite each other's keys. Prefix your save name with your mod's id (initSaveData('mymod_progress')) to stay out of other mods' data.