From 58bfba6c1e4a75523f76b8f73195f15a84ea7ec3 Mon Sep 17 00:00:00 2001
From: 47rooks <47rooks@gmail.com>
Date: Fri, 15 Dec 2023 08:39:15 -0800
Subject: [PATCH 1/6] Fix FlxSpriteGroup origin (#2981)

* update children origins relative to their positions

* add originTransform unit test
---
 flixel/group/FlxSpriteGroup.hx                |  2 +-
 .../src/flixel/group/FlxSpriteGroupTest.hx    | 27 +++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/flixel/group/FlxSpriteGroup.hx b/flixel/group/FlxSpriteGroup.hx
index 4f0c1b4955..26914d4d54 100644
--- a/flixel/group/FlxSpriteGroup.hx
+++ b/flixel/group/FlxSpriteGroup.hx
@@ -1057,7 +1057,7 @@ class FlxTypedSpriteGroup<T:FlxSprite> extends FlxSprite
 		Sprite.offset.copyFrom(Offset);
 
 	inline function originTransform(Sprite:FlxSprite, Origin:FlxPoint)
-		Sprite.origin.copyFrom(Origin);
+		Sprite.origin.set(x + origin.x - Sprite.x, y + origin.y - Sprite.y);
 
 	inline function scaleTransform(Sprite:FlxSprite, Scale:FlxPoint)
 		Sprite.scale.copyFrom(Scale);
diff --git a/tests/unit/src/flixel/group/FlxSpriteGroupTest.hx b/tests/unit/src/flixel/group/FlxSpriteGroupTest.hx
index 9218668a9e..744a07baf4 100644
--- a/tests/unit/src/flixel/group/FlxSpriteGroupTest.hx
+++ b/tests/unit/src/flixel/group/FlxSpriteGroupTest.hx
@@ -137,6 +137,33 @@ class FlxSpriteGroupTest extends FlxTest
 		Assert.isFalse(member2.revived);
 		return group;
 	}
+	@Test
+	/**
+	 * Ensure that member origins are correctly set when 
+	 * the group origin is set.
+	 */
+	function testOriginTransform()
+	{
+		var f1 = new FlxSprite(-10, 100);
+		var f2 = new FlxSprite(50, 50);
+		group.add(f1);
+		group.add(f2);
+		
+		group.setPosition(280, 300);
+		group.origin.set(300, 400);
+		
+		// Verify positions are updated - absolute
+		Assert.areEqual(270, f1.x);
+		Assert.areEqual(400, f1.y);
+		Assert.areEqual(330, f2.x);
+		Assert.areEqual(350, f2.y);
+		
+		// Verify origins are correct - relative
+		Assert.areEqual(310, f1.origin.x);
+		Assert.areEqual(300, f1.origin.y);
+		Assert.areEqual(250, f2.origin.x);
+		Assert.areEqual(350, f2.origin.y);
+	}
 }
 
 class Member extends FlxSprite

From c07122d6b9d9934e0d957517950d8e74587ff470 Mon Sep 17 00:00:00 2001
From: George Kurelic <Gkurelic@gmail.com>
Date: Fri, 15 Dec 2023 11:07:48 -0600
Subject: [PATCH 2/6] Better framerate independant camera lerping (#2922)

* adjust lerp based on the current frame rate

* better framerate independant camera lerping

* fix error

* remove setter

* docs

* fix default lerp in follow()

* fix typo
---
 flixel/FlxCamera.hx | 54 +++++++++++++++++++++------------------------
 1 file changed, 25 insertions(+), 29 deletions(-)

diff --git a/flixel/FlxCamera.hx b/flixel/FlxCamera.hx
index acf179f8a4..542ec606ee 100644
--- a/flixel/FlxCamera.hx
+++ b/flixel/FlxCamera.hx
@@ -126,12 +126,12 @@ class FlxCamera extends FlxBasic
 	public var targetOffset(default, null):FlxPoint = FlxPoint.get();
 
 	/**
-	 * Used to smoothly track the camera as it follows:
-	 * The percent of the distance to the follow `target` the camera moves per 1/60 sec.
-	 * Values are bounded between `0.0` and `60 / FlxG.updateFramerate` for consistency across framerates.
-	 * The maximum value means no camera easing. A value of `0` means the camera does not move.
+	 * The ratio of the distance to the follow `target` the camera moves per 1/60 sec.
+	 * Valid values range from `0.0` to `1.0`. `1.0` means the camera always snaps to its target
+	 * position. `0.5` means the camera always travels halfway to the target position, `0.0` means
+	 * the camera does not move. Generally, the lower the value, the more smooth.
 	 */
-	public var followLerp(default, set):Float = 60 / FlxG.updateFramerate;
+	public var followLerp:Float = 1.0;
 
 	/**
 	 * You can assign a "dead zone" to the camera in order to better control its movement.
@@ -1147,6 +1147,7 @@ class FlxCamera extends FlxBasic
 		if (target != null)
 		{
 			updateFollow();
+			updateLerp(elapsed);
 		}
 
 		updateScroll();
@@ -1194,7 +1195,7 @@ class FlxCamera extends FlxBasic
 	 * Updates camera's scroll.
 	 * Called every frame by camera's `update()` method (if camera's `target` isn't `null`).
 	 */
-	public function updateFollow():Void
+	function updateFollow():Void
 	{
 		// Either follow the object closely,
 		// or double check our deadzone and update accordingly.
@@ -1271,15 +1272,21 @@ class FlxCamera extends FlxBasic
 				_lastTargetPosition.y = target.y;
 			}
 		}
-
-		if (followLerp >= 60 / FlxG.updateFramerate)
+	}
+	
+	function updateLerp(elapsed:Float)
+	{
+		final boundLerp = FlxMath.bound(followLerp, 0, 1);
+		// Adjust lerp based on the current frame rate so lerp is less framerate dependant
+		final adjustedLerp = 1.0 - Math.pow(1.0 - boundLerp, elapsed * 60);
+		if (adjustedLerp >= 1)
 		{
 			scroll.copyFrom(_scrollTarget); // no easing
 		}
 		else
 		{
-			scroll.x += (_scrollTarget.x - scroll.x) * followLerp * (60 / FlxG.updateFramerate);
-			scroll.y += (_scrollTarget.y - scroll.y) * followLerp * (60 / FlxG.updateFramerate);
+			scroll.x += (_scrollTarget.x - scroll.x) * adjustedLerp;
+			scroll.y += (_scrollTarget.y - scroll.y) * adjustedLerp;
 		}
 	}
 
@@ -1456,29 +1463,23 @@ class FlxCamera extends FlxBasic
 	/**
 	 * Tells this camera object what `FlxObject` to track.
 	 *
-	 * @param   Target   The object you want the camera to track. Set to `null` to not follow anything.
-	 * @param   Style    Leverage one of the existing "deadzone" presets. Default is `LOCKON`.
+	 * @param   target   The object you want the camera to track. Set to `null` to not follow anything.
+	 * @param   style    Leverage one of the existing "deadzone" presets. Default is `LOCKON`.
 	 *                   If you use a custom deadzone, ignore this parameter and
 	 *                   manually specify the deadzone after calling `follow()`.
-	 * @param   Lerp     How much lag the camera should have (can help smooth out the camera movement).
+	 * @param   lerp     How much lag the camera should have (can help smooth out the camera movement).
 	 */
-	public function follow(Target:FlxObject, ?Style:FlxCameraFollowStyle, ?Lerp:Float):Void
+	public function follow(target:FlxObject, style = LOCKON, lerp = 1.0):Void
 	{
-		if (Style == null)
-			Style = LOCKON;
-
-		if (Lerp == null)
-			Lerp = 60 / FlxG.updateFramerate;
-
-		style = Style;
-		target = Target;
-		followLerp = Lerp;
+		this.style = style;
+		this.target = target;
+		followLerp = lerp;
 		var helper:Float;
 		var w:Float = 0;
 		var h:Float = 0;
 		_lastTargetPosition = null;
 
-		switch (Style)
+		switch (style)
 		{
 			case LOCKON:
 				if (target != null)
@@ -1925,11 +1926,6 @@ class FlxCamera extends FlxBasic
 		return contained;
 	}
 
-	function set_followLerp(Value:Float):Float
-	{
-		return followLerp = FlxMath.bound(Value, 0, 60 / FlxG.updateFramerate);
-	}
-
 	function set_width(Value:Int):Int
 	{
 		if (width != Value && Value > 0)

From 13bb9ab5213cf32aa0d045b74bf387b8e92a9278 Mon Sep 17 00:00:00 2001
From: George FunBook <gkurelic@gmail.com>
Date: Fri, 15 Dec 2023 14:33:28 -0600
Subject: [PATCH 3/6] add #2981 and #2922

---
 CHANGELOG.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3043d1a132..9179ef1edb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+6.0.0 (TBD)
+#### Changes and improvements:
+- `FlxSpritegroup`: Setting `origin` now causes members to pivot around the same point ([#2981](https://github.com/HaxeFlixel/flixel/pull/2981))
+- `FlxCamera`: Smoother camera lerping, particularly with non-fixed timesteps ([#2922](https://github.com/HaxeFlixel/flixel/pull/2922))
+
 5.6.0 (TBD)
 
 #### New features:

From 1d3d529e2c3bb1038b8625000cf4c58493ce2b9c Mon Sep 17 00:00:00 2001
From: George Kurelic <Gkurelic@gmail.com>
Date: Fri, 5 Jan 2024 17:43:51 -0600
Subject: [PATCH 4/6] Flxstate new (#2733)

* take FlxState constructor instead of FlxState

* add NextState type

* 4.0.5 fixes

* more 4.0.5 fixes

* fix deprecation warnings in unit tests

* take nextState in VCRFrontEnd

* remove @from Instance in InitialState

* use is operator

* improve docs

* rename method

* more docs

* more modular FlxSplash, set _gameJustStarted in FlxGame

* allow splash to be skipped by a switchState call
---
 flixel/FlxG.hx                                | 41 +++----------
 flixel/FlxGame.hx                             | 18 +++---
 flixel/FlxState.hx                            | 20 +-----
 flixel/util/typeLimit/NextState.hx            | 26 ++------
 tests/unit/src/TestMain.hx                    |  2 +-
 tests/unit/src/flixel/FlxCameraTest.hx        |  2 +-
 tests/unit/src/flixel/FlxObjectTest.hx        |  2 +-
 tests/unit/src/flixel/FlxStateTest.hx         | 61 ++++---------------
 tests/unit/src/flixel/FlxSubStateTest.hx      | 24 +++++---
 .../src/flixel/system/replay/FlxReplayTest.hx |  5 +-
 10 files changed, 54 insertions(+), 147 deletions(-)

diff --git a/flixel/FlxG.hx b/flixel/FlxG.hx
index 37e3b5e4d6..6ddbe8f81d 100644
--- a/flixel/FlxG.hx
+++ b/flixel/FlxG.hx
@@ -377,34 +377,13 @@ class FlxG
 	public static inline function switchState(nextState:NextState):Void
 	{
 		final stateOnCall = FlxG.state;
-		
-		if (!nextState.isInstance() || canSwitchTo(cast nextState))
+		state.startOutro(function()
 		{
-			state.startOutro(function()
-			{
-				if (FlxG.state == stateOnCall)
-					game._nextState = nextState;
-				else
-					FlxG.log.warn("`onOutroComplete` was called after the state was switched. This will be ignored");
-			});
-		}
-	}
-	
-	/**
-	 * Calls state.switchTo(nextState) without a deprecation warning.
-	 * This will be removed in Flixel 6.0.0
-	 * @since 5.6.0
-	 */
-	@:noCompletion
-	@:haxe.warning("-WDeprecated")
-	static function canSwitchTo(nextState:FlxState)
-	{
-		#if (haxe < version("4.3.0"))
-		// Use reflection because @:haxe.warning("-WDeprecated") doesn't work until haxe 4.3
-		return Reflect.callMethod(state, Reflect.field(state, 'switchTo'), [nextState]);
-		#else
-		return state.switchTo(nextState);
-		#end
+			if (FlxG.state == stateOnCall)
+				game._nextState = nextState;
+			else
+				FlxG.log.warn("`onOutroComplete` was called after the state was switched. This will be ignored");
+		});
 	}
 
 	/**
@@ -413,13 +392,7 @@ class FlxG
 	 */
 	public static inline function resetState():Void
 	{
-		if (state == null || state._constructor == null)
-			FlxG.log.error("FlxG.resetState was called while switching states");
-		else if(!state._constructor.isInstance())
-			switchState(state._constructor);
-		else
-			// create new instance here so that state.switchTo is called (for backwards compatibility)
-			switchState(Type.createInstance(Type.getClass(state), []));
+		switchState(state._constructor);
 	}
 
 	/**
diff --git a/flixel/FlxGame.hx b/flixel/FlxGame.hx
index 572958f885..912ed232bb 100644
--- a/flixel/FlxGame.hx
+++ b/flixel/FlxGame.hx
@@ -253,7 +253,8 @@ class FlxGame extends Sprite
 	 *                         [`scaleMode`](https://api.haxeflixel.com/flixel/system/scaleModes/index.html)
 	 *                         will determine the actual display size of the game.
 	 * @param initialState     A constructor for the initial state, ex: `PlayState.new` or `()->new PlayState()`.
-	 *                         Note: Also allows `Class<FlxState>` for backwards compatibility.
+	 *                         Note: Before Flixel 6, this took a `Class<FlxState>`, this has been
+	 *                         deprecated, but is still available, for backwards compatibility.
 	 * @param updateFramerate  How frequently the game should update. Default is 60 fps.
 	 * @param drawFramerate    Sets the actual display / draw framerate for the game. Default is 60 fps.
 	 * @param skipSplash       Whether you want to skip the flixel splash screen with `FLX_NO_DEBUG`.
@@ -628,7 +629,7 @@ class FlxGame extends Sprite
 
 		// Finally assign and create the new state
 		_state = _nextState.createInstance();
-		_state._constructor = _nextState;
+		_state._constructor = _nextState.getConstructor();
 		_nextState = null;
 
 		if (_gameJustStarted)
@@ -639,7 +640,10 @@ class FlxGame extends Sprite
 		_state.create();
 
 		if (_gameJustStarted)
-			gameStart();
+		{
+			FlxG.signals.postGameStart.dispatch();
+			_gameJustStarted = false;
+		}
 
 		#if FLX_DEBUG
 		debugger.console.registerObject("state", _state);
@@ -648,12 +652,6 @@ class FlxGame extends Sprite
 		FlxG.signals.postStateSwitch.dispatch();
 	}
 
-	function gameStart():Void
-	{
-		FlxG.signals.postGameStart.dispatch();
-		_gameJustStarted = false;
-	}
-
 	/**
 	 * This is the main game update logic section.
 	 * The `onEnterFrame()` handler is in charge of calling this
@@ -904,4 +902,4 @@ private class FlxIntroSplash extends FlxSplash
 		FlxG.game._gameJustStarted = true;
 		super.startOutro(onOutroComplete);
 	}
-}
\ No newline at end of file
+}
diff --git a/flixel/FlxState.hx b/flixel/FlxState.hx
index 24051dad25..3691071d39 100644
--- a/flixel/FlxState.hx
+++ b/flixel/FlxState.hx
@@ -11,10 +11,6 @@ import flixel.util.typeLimit.NextState;
  * It is for all intents and purpose a fancy `FlxGroup`. And really, it's not even that fancy.
  */
 @:keepSub // workaround for HaxeFoundation/haxe#3749
-#if FLX_NO_UNIT_TEST
-@:autoBuild(flixel.system.macros.FlxMacroUtil.deprecateOverride("switchTo", "switchTo is deprecated, use startOutro"))
-#end
-// show deprecation warning when `switchTo` is overriden in dereived classes
 class FlxState extends FlxGroup
 {
 	/**
@@ -52,7 +48,7 @@ class FlxState extends FlxGroup
 	 */
 	@:allow(flixel.FlxGame)
 	@:allow(flixel.FlxG)
-	var _constructor:NextState;
+	var _constructor:()->FlxState;
 	
 	/**
 	 * Current substate. Substates also can be nested.
@@ -105,7 +101,7 @@ class FlxState extends FlxGroup
 	 */
 	public function create():Void {}
 
-	override public function draw():Void
+	override function draw():Void
 	{
 		if (persistentDraw || subState == null)
 			super.draw();
@@ -186,18 +182,6 @@ class FlxState extends FlxGroup
 		super.destroy();
 	}
 
-	/**
-	 * Called from `FlxG.switchState()`. If `false` is returned, the state
-	 * switch is cancelled - the default implementation returns `true`.
-	 *
-	 * Useful for customizing state switches, e.g. for transition effects.
-	 */
-	@:deprecated("switchTo is deprecated, use startOutro")
-	public function switchTo(nextState:FlxState):Bool
-	{
-		return true;
-	}
-	
 	/**
 	 * Called from `FlxG.switchState()`, when `onOutroComplete` is called, the actual state
 	 * switching will happen.
diff --git a/flixel/util/typeLimit/NextState.hx b/flixel/util/typeLimit/NextState.hx
index d563541526..31825e809a 100644
--- a/flixel/util/typeLimit/NextState.hx
+++ b/flixel/util/typeLimit/NextState.hx
@@ -35,7 +35,7 @@ import flixel.FlxState;
 abstract NextState(Dynamic)
 {
 	@:from
-	// @:deprecated("use `MyState.new` or `()->new MyState()` instead of `new MyState()`)") // wait until 6.0.0
+	@:deprecated("use `MyState.new` or `()->new MyState()` instead of `new MyState()`)")
 	public static function fromState(state:FlxState):NextState
 	{
 		return cast state;
@@ -47,23 +47,11 @@ abstract NextState(Dynamic)
 		return cast func;
 	}
 	
-	@:allow(flixel.FlxG)
-	inline function isInstance():Bool
-	{
-		return this is FlxState;
-	}
-	
-	@:allow(flixel.FlxG)
-	inline function isClass():Bool
-	{
-		return this is Class;
-	}
-	
 	public function createInstance():FlxState
 	{
-		if (isInstance())
+		if (this is FlxState)
 			return cast this;
-		else if (isClass())
+		else if (this is Class)
 			return Type.createInstance(this, []);
 		else
 			return cast this();
@@ -71,18 +59,13 @@ abstract NextState(Dynamic)
 	
 	public function getConstructor():()->FlxState
 	{
-		if (isInstance())
+		if (this is FlxState)
 		{
 			return function ():FlxState
 			{
 				return cast Type.createInstance(Type.getClass(this), []);
 			}
 		}
-		else if (isClass())
-			return function ():FlxState
-			{
-				return cast Type.createInstance(this, []);
-			}
 		else
 			return cast this;
 	}
@@ -144,3 +127,4 @@ abstract InitialState(Dynamic) to NextState
 			return cast this;
 	}
 }
+
diff --git a/tests/unit/src/TestMain.hx b/tests/unit/src/TestMain.hx
index bc092e7186..5a4936b3d2 100644
--- a/tests/unit/src/TestMain.hx
+++ b/tests/unit/src/TestMain.hx
@@ -21,7 +21,7 @@ class TestMain
 	public function new()
 	{
 		// Flixel was not designed for unit testing so we can only have one instance for now.
-		Lib.current.stage.addChild(new FlxGame(640, 480, FlxState, 60, 60, true));
+		Lib.current.stage.addChild(new FlxGame(640, 480, FlxState.new, 60, 60, true));
 
 		var suites = new Array<Class<massive.munit.TestSuite>>();
 		suites.push(TestSuite);
diff --git a/tests/unit/src/flixel/FlxCameraTest.hx b/tests/unit/src/flixel/FlxCameraTest.hx
index 62eeb63819..85459f6094 100644
--- a/tests/unit/src/flixel/FlxCameraTest.hx
+++ b/tests/unit/src/flixel/FlxCameraTest.hx
@@ -47,7 +47,7 @@ class FlxCameraTest extends FlxTest
 	function testDefaultCamerasStateSwitch():Void
 	{
 		FlxCamera._defaultCameras = [FlxG.camera];
-		switchState(new FlxState());
+		switchState(FlxState.new);
 
 		Assert.areEqual(FlxG.cameras.defaults, FlxCamera._defaultCameras);
 	}
diff --git a/tests/unit/src/flixel/FlxObjectTest.hx b/tests/unit/src/flixel/FlxObjectTest.hx
index 292048bba0..69f3fafa70 100644
--- a/tests/unit/src/flixel/FlxObjectTest.hx
+++ b/tests/unit/src/flixel/FlxObjectTest.hx
@@ -159,7 +159,7 @@ class FlxObjectTest extends FlxTest
 
 	function velocityCollidingWith(ground:FlxObject)
 	{
-		switchState(new CollisionState());
+		switchState(CollisionState.new);
 
 		ground.setPosition(0, 10);
 		object1.setSize(10, 10);
diff --git a/tests/unit/src/flixel/FlxStateTest.hx b/tests/unit/src/flixel/FlxStateTest.hx
index 0bf2d46a0d..5f81512a98 100644
--- a/tests/unit/src/flixel/FlxStateTest.hx
+++ b/tests/unit/src/flixel/FlxStateTest.hx
@@ -16,15 +16,6 @@ class FlxStateTest extends FlxTest
 	@Ignore // TODO: investigate
 	function testSwitchState()
 	{
-		final state = new FlxState();
-		
-		Assert.areNotEqual(state, FlxG.state);
-		switchState(state);
-		Assert.areEqual(state, FlxG.state);
-		
-		// Make sure this compiles
-		switchState(FlxState.new);
-		
 		var nextState:FlxState = null;
 		function createState()
 		{
@@ -37,19 +28,20 @@ class FlxStateTest extends FlxTest
 	}
 
 	@Test
-	function testResetStateInstance()
+	@:haxe.warning("-WDeprecated")
+	function testResetStateLegacy()
 	{
-		var state = new TestState();
-		switchState(state);
+		switchState(TestState.new);
+		var state = FlxG.state;
 		Assert.areEqual(state, FlxG.state);
 
 		resetState();
 		Assert.areNotEqual(state, FlxG.state);
-		Assert.isTrue((FlxG.state is TestState));
+		Assert.isTrue(FlxG.state is TestState);
 	}
 
 	@Test
-	function testResetStateFunction()
+	function testResetState()
 	{
 		var nextState:TestState = null;
 		function createState()
@@ -68,28 +60,11 @@ class FlxStateTest extends FlxTest
 	}
 	
 	@Test // #1676
-	function testCancelStateSwitchInstance()
-	{
-		var finalState = new FinalStateLegacy();
-		switchState(finalState);
-		Assert.areEqual(finalState, FlxG.state);
-
-		switchState(new FlxState());
-		Assert.areEqual(finalState, FlxG.state);
-
-		resetState();
-		Assert.areEqual(finalState, FlxG.state);
-	}
-	
-	@Test // #1676
-	function testCancelStateSwitchFunction()
+	function testCancelStateSwitch()
 	{
 		switchState(FinalState.new);
 		final finalState = FlxG.state;
 
-		switchState(new FlxState());
-		Assert.areEqual(finalState, FlxG.state);
-
 		switchState(FlxState.new);
 		Assert.areEqual(finalState, FlxG.state);
 
@@ -100,27 +75,15 @@ class FlxStateTest extends FlxTest
 	@Test
 	function testOutro()
 	{
-		var outroState = new OutroState();
-		
-		FlxG.switchState(outroState);
+		FlxG.switchState(OutroState.new);
 		step();
-		Assert.areEqual(outroState, FlxG.state);
+		Assert.isType(FlxG.state, OutroState);
 		
-		FlxG.switchState(new FlxState());
+		FlxG.switchState(FlxState.new);
 		step();
-		Assert.areEqual(outroState, FlxG.state);
+		Assert.isType(FlxG.state, OutroState);
 		step();
-		Assert.areNotEqual(outroState, FlxG.state);
-		
-	}
-}
-
-class FinalStateLegacy extends FlxState
-{
-	/* prevents state switches */
-	override function switchTo(state)
-	{
-		return false;
+		Assert.isNotType(FlxG.state, OutroState);
 	}
 }
 
diff --git a/tests/unit/src/flixel/FlxSubStateTest.hx b/tests/unit/src/flixel/FlxSubStateTest.hx
index af0389574a..acc26c9a96 100644
--- a/tests/unit/src/flixel/FlxSubStateTest.hx
+++ b/tests/unit/src/flixel/FlxSubStateTest.hx
@@ -41,28 +41,25 @@ class FlxSubStateTest extends FlxTest
 	@Test // #1971
 	function testOpenPersistentSubStateFromNewParent()
 	{
-		var state1 = new FlxState();
-		var state2 = new FlxState();
-		state1.destroySubStates = false;
-		FlxG.switchState(state1);
+		FlxG.switchState(FlxStateNoDestroySubState.new.bind(false));
 		step();
 		FlxG.state.openSubState(subState1);
 		step();
 
-		Assert.areEqual(state1.subState, subState1);
+		Assert.areEqual(FlxG.state.subState, subState1);
 		subState1.close();
 		step();
-		Assert.isNull(state1.subState);
+		Assert.isNull(FlxG.state.subState);
 
-		FlxG.switchState(state2);
+		FlxG.switchState(FlxStateNoDestroySubState.new.bind(true));
 		step();
 		FlxG.state.openSubState(subState1);
 		step();
 
-		Assert.areEqual(state2.subState, subState1);
+		Assert.areEqual(FlxG.state.subState, subState1);
 		subState1.close();
 		step();
-		Assert.isNull(state2.subState);
+		Assert.isNull(FlxG.state.subState);
 	}
 
 	@Test // #2023
@@ -87,3 +84,12 @@ class FlxSubStateTest extends FlxTest
 		Assert.isTrue(closed);
 	}
 }
+
+class FlxStateNoDestroySubState extends FlxState
+{
+	public function new (destroySubStates)
+	{
+		super();
+		this.destroySubStates = destroySubStates;
+	}
+}
\ No newline at end of file
diff --git a/tests/unit/src/flixel/system/replay/FlxReplayTest.hx b/tests/unit/src/flixel/system/replay/FlxReplayTest.hx
index 85a6d564a5..84212a11d1 100644
--- a/tests/unit/src/flixel/system/replay/FlxReplayTest.hx
+++ b/tests/unit/src/flixel/system/replay/FlxReplayTest.hx
@@ -90,12 +90,11 @@ class FlxReplayTest extends FlxTest
 			createFrameRecord(3, JUST_RELEASED)
 		];
 		var recording = frames.map(function(r) return r.save()).join("\n");
-		var state = new ReplayState();
-		FlxG.vcr.loadReplay(recording, state);
+		FlxG.vcr.loadReplay(recording, ReplayState.new);
 
 		step(10);
 
-		Assert.isTrue(state.called);
+		Assert.isTrue((cast FlxG.state:ReplayState).called);
 	}
 
 	function createFrameRecord(i:Int, mouseState:FlxInputState):FrameRecord

From b03dbacafcbb7164ea01afb0f2af137485c51a41 Mon Sep 17 00:00:00 2001
From: George Kurelic <Gkurelic@gmail.com>
Date: Sun, 7 Jan 2024 18:57:17 -0600
Subject: [PATCH 5/6] touch-ups for #2733 (#3003)

* take FlxState constructor instead of FlxState

* add NextState type

* 4.0.5 fixes

* more 4.0.5 fixes

* fix deprecation warnings in unit tests

* take nextState in VCRFrontEnd

* remove @from Instance in InitialState

* use is operator

* improve docs

* rename method

* more docs

* more modular FlxSplash, set _gameJustStarted in FlxGame

* allow splash to be skipped by a switchState call

* touch-ups
---
 flixel/FlxGame.hx                  | 13 ++++++++-----
 flixel/util/typeLimit/NextState.hx |  5 ++---
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/flixel/FlxGame.hx b/flixel/FlxGame.hx
index 912ed232bb..d49f7640db 100644
--- a/flixel/FlxGame.hx
+++ b/flixel/FlxGame.hx
@@ -640,10 +640,7 @@ class FlxGame extends Sprite
 		_state.create();
 
 		if (_gameJustStarted)
-		{
-			FlxG.signals.postGameStart.dispatch();
-			_gameJustStarted = false;
-		}
+			gameStart();
 
 		#if FLX_DEBUG
 		debugger.console.registerObject("state", _state);
@@ -651,6 +648,12 @@ class FlxGame extends Sprite
 
 		FlxG.signals.postStateSwitch.dispatch();
 	}
+	
+	function gameStart()
+	{
+		FlxG.signals.postGameStart.dispatch();
+		_gameJustStarted = false;
+	}
 
 	/**
 	 * This is the main game update logic section.
@@ -902,4 +905,4 @@ private class FlxIntroSplash extends FlxSplash
 		FlxG.game._gameJustStarted = true;
 		super.startOutro(onOutroComplete);
 	}
-}
+}
\ No newline at end of file
diff --git a/flixel/util/typeLimit/NextState.hx b/flixel/util/typeLimit/NextState.hx
index 31825e809a..7192878532 100644
--- a/flixel/util/typeLimit/NextState.hx
+++ b/flixel/util/typeLimit/NextState.hx
@@ -74,7 +74,7 @@ abstract NextState(Dynamic)
 /**
  * A utility type that allows methods to accept multiple types, when dealing with "future" `FlxStates`.
  * Prior to haxeFlixel 6, the `FlxGame` constructor took a `FlxState` class which meant initial
- `FlxStates`could not have constructor args. In version 6.0.0 and higher, it now takes a function
+ * `FlxStates`could not have constructor args. In version 6.0.0 and higher, it now takes a function
  * that returns a newly created instance.
  * 
  * ## examples:
@@ -126,5 +126,4 @@ abstract InitialState(Dynamic) to NextState
 		else
 			return cast this;
 	}
-}
-
+}
\ No newline at end of file

From eb78d5c80d91f9a1304a37fc4c7f05ed1aea5d69 Mon Sep 17 00:00:00 2001
From: George FunBook <gkurelic@gmail.com>
Date: Wed, 24 Jan 2024 14:19:06 -0600
Subject: [PATCH 6/6] add #2733

---
 CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 54793c3e18..b555e2facc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 #### Changes and improvements:
 - `FlxSpritegroup`: Setting `origin` now causes members to pivot around the same point ([#2981](https://github.com/HaxeFlixel/flixel/pull/2981))
 - `FlxCamera`: Smoother camera lerping, particularly with non-fixed timesteps ([#2922](https://github.com/HaxeFlixel/flixel/pull/2922))
+- `FlxState`: Remove deprecated `switchTo` ([#2733](https://github.com/HaxeFlixel/flixel/pull/2733))Z
+- `FlxG`: Add deprecation warning on `switchState` with instances ([#2733](https://github.com/HaxeFlixel/flixel/pull/2733))Z
 
 5.6.0 (TBD)