Animator

Drives an animator controller — the state machine that decides which clip plays. For building the controller itself, see the 2D Animation guide.

public class Player : GameEntity
{
    private Animator? m_Anim;

    protected override void OnCreate()
    {
        m_Anim = GetComponent<Animator>();
    }

    protected override void OnUpdate(float ts)
    {
        m_Anim?.SetFloat("Speed", System.Math.Abs(m_Velocity.X));
        m_Anim?.SetBool("Grounded", m_Grounded);
    }

    public void Jump() => m_Anim?.SetTrigger("Jump");
}

Parameters

Controller transitions are driven by named parameters you set from script.

Method	Notes
SetFloat(string name, float value)	For blend conditions like walk speed
SetInt(string name, int value)	For discrete states like a weapon index
SetBool(string name, bool value)	Stays where you put it
SetTrigger(string name)	A one-shot pulse, consumed by the transition that fires on it
ResetTrigger(string name)	Clears a trigger that was set but never consumed
GetFloat(string name)	Reads a float parameter back
GetInt(string name)	Reads an int parameter back
GetBool(string name)	Reads a bool parameter back

Bool or trigger?

A bool describes a lasting condition — Grounded, Crouching. A trigger describes a moment — Jump, Hit. Using a bool for a moment means remembering to clear it; using a trigger for a condition means it fires once and the state never comes back. ResetTrigger is for the case where you set a trigger and then the situation changed before any transition consumed it.

State

CurrentState

The name of the state the animator is in right now.

if (m_Anim.CurrentState == "Death")
    DisableInput();

NormalizedTime

How far through the current state's clip you are, where 0 is the start and 1 is the end. A looping clip keeps counting past 1.

if (m_Anim.CurrentState == "Attack" && m_Anim.NormalizedTime > 0.6f)
    EnableHitbox();

IsTransitioning

true while a transition between two states is in progress.

IsPlaying

true while the animator is running (not paused).

Playback

Play(string stateName, float normalizedTime = 0.0f)

Jumps straight to a state, ignoring transitions. Optionally starts partway through.

m_Anim.Play("Idle");
m_Anim.Play("Death", 0.5f);   // start halfway in

CrossFade(string stateName, float duration)

Blends into a state over duration seconds — the smooth counterpart to Play.

m_Anim.CrossFade("Run", 0.15f);

Speed

A multiplier on playback speed. 1 is authored speed, 0.5 is half, 2 is double. Read and write.

m_Anim.Speed = m_Slowed ? 0.4f : 1.0f;

Pause() / Resume()

Stop and restart playback where it is.

Reacting to state changes

Animator notifications are GameEntity overrides, not C# events — see Components for why.

protected override void OnAnimatorStateEntered(string stateName)
{
    if (stateName == "Attack")
        m_SwingSound?.Play();
}

protected override void OnAnimatorStateExited(string stateName) { }

protected override void OnAnimatorPose()
{
    // Layer procedural motion on top of the sampled clip.
    Translation += m_Recoil;
}

Exited and Entered fire once per transition, in that order. OnAnimatorPose runs after the animator has written this frame's pose, which is what lets you add recoil, a look-at or breathing on top of a clip without the next frame's sample wiping it out.

There was once an event here

Earlier versions declared Animator.StateEntered as a C# event. Nothing could ever raise it, so subscribing did nothing at all. It was removed rather than left as a trap — use the overrides above.

Animation events

A clip's event track can call a method on your script by name. Mark the method so the engine will dispatch to it:

[AnimationEvent]
private void Footstep()
{
    m_StepSound?.Play();
}

[AnimationEvent]
private void SpawnEffect(string effectName)
{
    Particles.Spawn($"Effects/{effectName}.jparticle", Translation);
}

Supported signatures are void F(), void F(string), void F(float) and void F(int). An unsupported signature is reported once in the log and the event is skipped — playback never crashes over it.

The attribute is required. A method without it can't be called from a clip, which keeps an animation from reaching arbitrary methods on a script that never opted in. See Attributes.

Animation.Sample(GameEntity entity, string clipPath, float time)

Applies one frame of a clip to an entity directly, with no animator involved — for posing something at a fixed moment. The entity needs whatever components the clip's tracks target.

Animation.Sample(this, "Animations/Wave.janim", 0.5f);

See also

• 2D Animation — building sprite sheets, clips, and controllers
• GameEntity — the animator lifecycle hooks
• Attributes — [AnimationEvent]