Transition crash fix again + changeable transition script (#493)

* fix transition crash when skipping

* transition crash fix again

* rename transition script var

* better transition scripting

* add more transition script functions

* move post create to actually be after

* change this

* actually destroy the script

* add a variable to disable skipping the transition

* opa

idk felt better like this

---------

Co-authored-by: ⍚~Nex <87421482+NexIsDumb@users.noreply.github.com>

source/funkin/backend/MusicBeatTransition.hx

@@ -1,15 +1,24 @@
 package funkin.backend;
 
+import funkin.backend.scripting.events.CancellableEvent;
+import funkin.backend.scripting.events.TransitionCreationEvent;
+import funkin.backend.scripting.Script;
 import flixel.tweens.FlxTween;
 import flixel.FlxState;
 import funkin.backend.utils.FunkinParentDisabler;
 
 class MusicBeatTransition extends MusicBeatSubstate {
+	public static var script:String = "";
+	public var transitionScript:Script;
+
 	var nextFrameSkip:Bool = false;
 
 	public var transitionTween:FlxTween = null;
 	public var transitionCamera:FlxCamera;
 	public var newState:FlxState;
+	public var transOut:Bool = false;
+
+	public var allowSkip:Bool = true;
 
 	public var blackSpr:FlxSprite;
 	public var transitionSprite:FunkinSprite;
@@ -20,16 +29,30 @@ class MusicBeatTransition extends MusicBeatSubstate {
 
 	public override function create() {
 		if (newState != null)
-			add(new FunkinParentDisabler(true));
+			add(new FunkinParentDisabler(true, false));
 
 		transitionCamera = new FlxCamera();
 		transitionCamera.bgColor = 0;
 		FlxG.cameras.add(transitionCamera, false);
 
 		cameras = [transitionCamera];
-		var out = newState != null;
 
-		blackSpr = new FlxSprite(0, out ? -transitionCamera.height : transitionCamera.height).makeGraphic(1, 1, -1);
+		transitionScript = Script.create(Paths.script(script));
+		transitionScript.setParent(this);
+		transitionScript.load();
+
+		var event = EventManager.get(TransitionCreationEvent).recycle(newState != null, newState);
+		transitionScript.call('create', [event]);
+
+		transOut = event.transOut;
+		newState = event.newState;
+
+		if (event.cancelled) {
+			super.create();
+			return;
+		}
+
+		blackSpr = new FlxSprite(0, transOut ? -transitionCamera.height : transitionCamera.height).makeGraphic(1, 1, -1);
 		blackSpr.scale.set(transitionCamera.width, transitionCamera.height);
 		blackSpr.color = 0xFF000000;
 		blackSpr.updateHitbox();
@@ -43,7 +66,7 @@ class MusicBeatTransition extends MusicBeatSubstate {
 		} else {
 			transitionSprite.screenCenter();
 		}
-		transitionCamera.flipY = !out;
+		transitionCamera.flipY = !transOut;
 		add(transitionSprite);
 
 		transitionCamera.scroll.y = transitionCamera.height;
@@ -55,41 +78,59 @@ class MusicBeatTransition extends MusicBeatSubstate {
 		});
 
 		super.create();
+		transitionScript.call('postCreate', [event]);
 	}
 
 	public override function update(elapsed:Float) {
+		transitionScript.call('update', [elapsed]);
 		super.update(elapsed);
 
 		if (nextFrameSkip) {
-			finish();
-			return;
+			var event = new CancellableEvent();
+			transitionScript.call('onSkip', [event]);
+			if (!event.cancelled) {
+				finish();
+				return;
+			}
 		}
 
-		if (!parent.persistentUpdate && FlxG.keys.pressed.SHIFT) {
+		if (allowSkip && !parent.persistentUpdate && FlxG.keys.pressed.SHIFT) {
 			// skip
 			if (newState != null) {
 				nextFrameSkip = true;
 				parent.persistentDraw = false;
 			} else {
-				finish();
+				var event = new CancellableEvent();
+				transitionScript.call('onSkip', [event]);
+				if (!event.cancelled) {
+					finish();
+				}
 			}
 		}
+		transitionScript.call('postUpdate', [elapsed]);
 	}
 
 	public function finish() {
+		var event = new CancellableEvent();
+		transitionScript.call('onFinish', [event]);
+		if (event.cancelled) return;
+
 		if (newState != null)
 			FlxG.switchState(newState);
 		close();
+
+		transitionScript.call('onPostFinish');
 	}
 
 	public override function destroy() {
-		if (transitionTween != null)
-			transitionTween.cancel();
+		transitionScript.call('destroy');
+
+		if (transitionTween != null) transitionTween.cancel();
 		transitionTween = FlxDestroyUtil.destroy(transitionTween);
-		if (newState == null && FlxG.cameras.list.contains(transitionCamera))
-			FlxG.cameras.remove(transitionCamera);
-		else
-			transitionCamera.bgColor = 0xFF000000;
+		if (newState == null && FlxG.cameras.list.contains(transitionCamera)) FlxG.cameras.remove(transitionCamera);
+		else transitionCamera.bgColor = 0xFF000000;
+
+		transitionScript.destroy();
 		super.destroy();
 	}
 }

source/funkin/backend/scripting/events/TransitionCreationEvent.hx

@@ -0,0 +1,18 @@
+package funkin.backend.scripting.events;
+
+import flixel.FlxState;
+
+/**
+ * CANCEL this event to prevent default behaviour!
+ */
+final class TransitionCreationEvent extends CancellableEvent {
+	/**
+	 * If the transition is going out into another state
+	 */
+	public var transOut:Bool;
+
+	/**
+	 * The state that is about to be loaded (only on trans out)
+	 */
+	public var newState:FlxState;
+}

source/funkin/backend/system/MainState.hx

@@ -53,6 +53,7 @@ class MainState extends FlxState {
 		}
 		#end
 
+		MusicBeatTransition.script = "";
 		Main.refreshAssets();
 		ModsFolder.onModSwitch.dispatch(ModsFolder.currentModFolder);
 		DiscordUtil.init();

source/funkin/backend/utils/FunkinParentDisabler.hx

@@ -19,9 +19,11 @@ class FunkinParentDisabler extends FlxBasic {
 	var __timers:Array<FlxTimer>;
 	var __sounds:Array<FlxSound>;
 	var __replaceUponDestroy:Bool;
-	public function new(replaceUponDestroy:Bool = false) {
+	var __restoreUponDestroy:Bool;
+	public function new(replaceUponDestroy:Bool = false, restoreUponDestroy:Bool = true) {
 		super();
 		__replaceUponDestroy = replaceUponDestroy;
+		__restoreUponDestroy = restoreUponDestroy;
 		@:privateAccess {
 			// tweens
 			__tweens = FlxTween.globalManager._tweens.copy();
@@ -53,6 +55,11 @@ class FunkinParentDisabler extends FlxBasic {
 	public override function destroy() {
 		super.destroy();
 		@:privateAccess {
+			if (!__restoreUponDestroy) {
+				for(t in __tweens) { t.cancel(); t.destroy(); };
+				for(t in __timers) { t.cancel(); t.destroy(); };
+				return;
+			}
 			if (__replaceUponDestroy) {
 				FlxTween.globalManager._tweens = __tweens;
 				FlxTimer.globalManager._timers = __timers;