animation-patterns

Animation Patterns

Godot AnimationTree BlendSpace2D Locomotion

# Locomotion blend tree setup - driven by velocity
class_name PlayerAnimator extends Node
@onready var animation_tree: AnimationTree = $AnimationTree
@onready var body: CharacterBody3D = get_parent()

const BLEND_PATH := "parameters/LocomotionBlend/blend_position"
const SPEED_PATH := "parameters/SpeedBlend/blend_amount"

func _physics_process(_delta: float) -> void:
    var velocity := body.velocity
    var speed := velocity.length()

    # 2D blend space: X=strafe (-1 left, 1 right), Y=forward (0 idle, 1 run)
    # Normalize by max speed so blend space uses [0,1] range
    var horizontal := body.global_transform.basis.x.dot(velocity) / 6.0
    var forward := -body.global_transform.basis.z.dot(velocity) / 6.0

    animation_tree.set(BLEND_PATH, Vector2(horizontal, forward))
    animation_tree.set(SPEED_PATH, speed / 6.0)  # 6.0 = max run speed

# AnimationTree configuration (in Godot editor):
# Root: AnimationNodeStateMachine
#   State "Locomotion": AnimationNodeBlendSpace2D
#     Points:
#       (0, 0) = "idle" clip
#       (0, 1) = "run_forward" clip
#       (1, 0) = "strafe_right" clip
#       (-1, 0) = "strafe_left" clip
#       (0, -1) = "walk_backward" clip
#     Blend mode: Interpolation (linear)
#   State "Jump": AnimationNodeAnimation ("jump" clip, no loop)
#   State "Land": AnimationNodeAnimation ("land" clip, no loop)
#   Transitions:
#     Locomotion -> Jump: condition "is_jumping" (bool param)
#     Jump -> Land: advance condition "animation_finished"
#     Land -> Locomotion: advance condition "animation_finished"

AnimationNodeStateMachine Transitions (GDScript)

# Trigger state transitions through AnimationTree parameters
func jump() -> void:
    animation_tree.set("parameters/conditions/is_jumping", true)
    # Reset after one frame so it acts as a trigger
    await get_tree().process_frame
    animation_tree.set("parameters/conditions/is_jumping", false)

func land() -> void:
    animation_tree.set("parameters/conditions/is_landing", true)
    await get_tree().process_frame
    animation_tree.set("parameters/conditions/is_landing", false)

# Reading current state name for logic decisions
func get_current_animation() -> StringName:
    var playback: AnimationNodeStateMachinePlayback = animation_tree.get(
        "parameters/playback"
    )
    return playback.get_current_node()

func is_in_state(state_name: StringName) -> bool:
    return get_current_animation() == state_name