How do I properly flip a 2D rigged character with IK and LookAt in Godot 4?

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1

Godot Version

4.6

Question

Hi, I have a CharacterBody2D with a fully rigged 2D character using Skeleton2D, FABRIK and CCDIK for arms/legs, and a LookAtModifier2D for the head.

I want my character to flip left/right based on movement.

Current issues:

  • Using scale.x = -1 on the root flips the head vertically (LookAt breaks).

  • The feet IK doesn’t mirror correctly.

  • Animations become unstable when mirroring the skeleton.

What’s the best practice way to flip a 2D character with IK and LookAt?

  • Should I flip the root node, Skeleton2D, or just adjust IK targets?

  • Should the head/feet targets be flipped separately?

  • Are there recommended node hierarchies or scripts for stable flipping?

I’d appreciate any examples in GDScript or explanations of why certain flipping approaches break IK/LookAt.

Thanks!

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3

Is the head rotated by default? that could be the issue.
Yes, usually calling self.scale.x = -1 on the entire node works and is fine, in this case though its kinda hard to say why it isnt working other than the above hypothesis.

4

Use SoupIK Instead. Flipping the head separately is up to you.

This is what mine looks like. You flip everything.

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Here’s the code on the Facing node.

extends Node2D

@onready var player: Player = get_parent()
@onready var player_movement_state_machine: StateMachine = %"Player Movement State Machine"
@onready var collision_shape_2d: CollisionShape2D = $"../CollisionShape2D"
@onready var character_skin: CharacterSkin = %CharacterSkin


func _physics_process(_delta: float) -> void:
	var new_horizontal_facing: float = scale.x
	if player.direction < 0:
		new_horizontal_facing = -1.0
	elif player.direction > 0:
		new_horizontal_facing = 1.0
	if player_movement_state_machine._current_state is WallSlidePlayerState:
		new_horizontal_facing *= -1.0
	if new_horizontal_facing != scale.x:
		scale.x = new_horizontal_facing
		character_skin.flip_horizontal = new_horizontal_facing < 0
	
	var new_vertical_facing: float = scale.y
	if player.get_gravity().y <= 0:
		new_vertical_facing = -1.0
	elif player.get_gravity().y > 0:
		new_vertical_facing = 1.0
	if new_vertical_facing != scale.y:
		scale.y = new_vertical_facing
		character_skin.flip_vertical = new_vertical_facing < 0