Add FunkinBackdrop

source/funkin/backend/FunkinBackdrop.hx

@@ -0,0 +1,152 @@
+package funkin.backend;
+
+import flixel.FlxCamera;
+import flixel.FlxG;
+import flixel.addons.display.FlxBackdrop;
+import flixel.math.FlxMath;
+import flixel.math.FlxRect;
+import flixel.util.FlxAxes;
+import flixel.util.FlxColor;
+import funkin.backend.system.Flags;
+
+class FunkinBackdrop extends FlxBackdrop
+{
+	public var zoomFactor:Float = 1;
+	public var zoomFactorEnabled:Bool = true;
+	public var angleFactor:Float = 1;
+	public var angleFactorEnabled:Bool = true;
+
+	private var _rect2:FlxRect;
+
+	public function new(?graphic:Dynamic, repeatAxes = XY, spacingX:Int = 0, spacingY:Int = 0)
+	{
+		super(graphic, repeatAxes, spacingX, spacingY);
+		_rect2 = FlxRect.get();
+		antialiasing = true;
+	}
+
+	private inline function __shouldDoZoomFactor():Bool
+	{
+		return zoomFactorEnabled && zoomFactor != 1 && camera != null;
+	}
+
+	private inline function __getZoomScaleX(camera:FlxCamera):Float
+	{
+		return (camera.scaleX > 0 ? Math.max : Math.min)(0, FlxMath.lerp(1 / camera.scaleX, 1, zoomFactor));
+	}
+
+	private inline function __getZoomScaleY(camera:FlxCamera):Float
+	{
+		return (camera.scaleY > 0 ? Math.max : Math.min)(0, FlxMath.lerp(1 / camera.scaleY, 1, zoomFactor));
+	}
+
+	private inline function __getZoomAnchorX(camera:FlxCamera):Float
+	{
+		if (Flags.USE_LEGACY_ZOOM_FACTOR)
+			return camera.width * 0.5 - origin.x;
+
+		return camera.width * 0.5 + camera.scroll.x * scrollFactor.x - origin.x;
+	}
+
+	private inline function __getZoomAnchorY(camera:FlxCamera):Float
+	{
+		if (Flags.USE_LEGACY_ZOOM_FACTOR)
+			return camera.height * 0.5 - origin.y;
+
+		return camera.height * 0.5 + camera.scroll.y * scrollFactor.y - origin.y;
+	}
+
+	private inline function __shouldDoAngleFactor():Bool
+	{
+		return angleFactorEnabled && angleFactor != 1 && camera != null;
+	}
+
+	private inline function __getAngleAnchorX(camera:FlxCamera):Float
+	{
+		if (Flags.USE_LEGACY_ZOOM_FACTOR)
+			return camera.width * 0.5 - origin.x;
+
+		return camera.width * 0.5 + camera.scroll.x * scrollFactor.x - origin.x;
+	}
+
+	private inline function __getAngleAnchorY(camera:FlxCamera):Float
+	{
+		if (Flags.USE_LEGACY_ZOOM_FACTOR)
+			return camera.height * 0.5 - origin.y;
+
+		return camera.height * 0.5 + camera.scroll.y * scrollFactor.y - origin.y;
+	}
+
+	private inline function __prepareAngleFactor(camera:FlxCamera):Float
+	{
+		return FlxMath.lerp(-camera.angle, 0, angleFactor);
+	}
+
+	override public function draw():Void
+	{
+		if (!__shouldDoZoomFactor() && !__shouldDoAngleFactor())
+		{
+			super.draw();
+			return;
+		}
+
+		var camera:FlxCamera = this.camera;
+		if (camera == null)
+			camera = FlxG.camera;
+
+		var oldX:Float = x;
+		var oldY:Float = y;
+		var oldScaleX:Float = scale.x;
+		var oldScaleY:Float = scale.y;
+		var oldAngle:Float = angle;
+
+		if (__shouldDoZoomFactor())
+		{
+			var zoomScaleX:Float = __getZoomScaleX(camera);
+			var zoomScaleY:Float = __getZoomScaleY(camera);
+
+			var anchorX:Float = __getZoomAnchorX(camera);
+			var anchorY:Float = __getZoomAnchorY(camera);
+
+			x = (x - anchorX) * zoomScaleX + anchorX;
+			y = (y - anchorY) * zoomScaleY + anchorY;
+
+			scale.set(scale.x * zoomScaleX, scale.y * zoomScaleY);
+		}
+
+		if (__shouldDoAngleFactor())
+		{
+			var anchorX:Float = __getAngleAnchorX(camera);
+			var anchorY:Float = __getAngleAnchorY(camera);
+			var prepAngle:Float = __prepareAngleFactor(camera);
+
+			var rad:Float = prepAngle * (Math.PI / 180);
+			var cos:Float = Math.cos(rad);
+			var sin:Float = Math.sin(rad);
+
+			var dx:Float = x - anchorX;
+			var dy:Float = y - anchorY;
+
+			x = dx * cos - dy * sin + anchorX;
+			y = dx * sin + dy * cos + anchorY;
+			angle += prepAngle;
+		}
+
+		super.draw();
+
+		x = oldX;
+		y = oldY;
+		scale.set(oldScaleX, oldScaleY);
+		angle = oldAngle;
+	}
+
+	override public function destroy():Void
+	{
+		if (_rect2 != null)
+		{
+			_rect2.put();
+			_rect2 = null;
+		}
+		super.destroy();
+	}
+}

source/funkin/backend/scripting/Script.hx

@@ -105,6 +105,7 @@ class Script extends FlxBasic implements IFlxDestroyable {
 			"FunkinText"		=> funkin.backend.FunkinText,
 			"FlxAnimate"		=> animate.FlxAnimate,
 			"FunkinSprite"		=> funkin.backend.FunkinSprite,
+			"FunkinBackdrop"	=> funkin.backend.FunkinBackdrop,
 			"Alphabet"			=> funkin.menus.ui.Alphabet,
 			"Flags"				=> funkin.backend.system.Flags,