Version: Unity 6.1 Alpha (6000.1)
LanguageEnglish
  • C#

StateMachineBehaviour

class in UnityEngine

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Inherits from:ScriptableObject

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Implemented in:UnityEngine.AnimationModule

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Description

StateMachineBehaviour is a component that can be added to a state machine state. It's the base class any script on a state must derive from.

State machines can have up to three different active states at the same time: the current state, the next state and the interrupted state.
The state machine always has a current state. When the state machine transitions to a new state, a "next state" is added. Once the transition is complete, the current state is terminated and the next state becomes the new current state.
If an ongoing transition is interrupted by a transition to a new state, then the next state becomes the interrupted state and the state targeted by the new transition is now the next state. The current state will remain the same until all interrupted transitions have completed. Once the last transition is complete and there are no more interruptions, the current and interrupted states are terminated, and the next state becomes the new current state.

StateMachineBehaviour has some predefined state-related messages that you can implement:OnStateEnter, OnStateExit, OnStateIK, OnStateMove, OnStateUpdate.
Whenever appropriate, these messages will be invoked for the active states mentioned above in the following order: current state, then interrupted state, then next state.
See the description of each message for more information.

StateMachineBehaviour also has some predefined messages related to transitions in and out of state machines:
OnStateMachineEnter, OnStateMachineExit.
These are invoked whenever a state machine transition is taken.

Layer considerations:
If an AnimatorController contains sychronized layers, the messages may be invoked multiple times for a single state. In that situation, the messages will be invoked once per synchronized layer that contains the state, in ascending order.

Additional considerations:
By default the Animator instantiates a new instance of each behaviour defined in the controller. If you wish to share behaviour instances, use the class attribute SharedBetweenAnimatorsAttribute to control how behaviours are instantiated.

using UnityEngine;

public class AttackBehaviour : StateMachineBehaviour { public GameObject particle; public float radius; public float power;

protected GameObject clone;

override public void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) { clone = Instantiate(particle, animator.rootPosition, Quaternion.identity) as GameObject; Rigidbody rb = clone.GetComponent<Rigidbody>(); rb.AddExplosionForce(power, animator.rootPosition, radius, 3.0f); }

override public void OnStateExit(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) { Destroy(clone); }

override public void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) { Debug.Log("On Attack Update "); }

override public void OnStateMove(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) { Debug.Log("On Attack Move "); }

override public void OnStateIK(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) { Debug.Log("On Attack IK "); } }

Public Methods

OnStateMachineEnterInvoked on the first update frame when taking a transition into a state machine. Implement this message to influence the entry transition into the sub-state machine.
OnStateMachineExitInvoked on the last update frame when taking a transition out of a StateMachine. Implement this message to influence the exit transition out of the sub-state machine

Messages

OnStateEnterInvoked on the first update frame when a state machine evaluates this state. Implement this message to react to a new state starting.
OnStateExitInvoked on the last update frame when a state machine evaluates this state. Implement this message to react to a state ending.
OnStateIKInvoked during the Animator IK pass. Implement this message to modify the result of the animation after the evaluation of the state machine on a state by state basis.
OnStateMoveInvoked during the Animator Root Motion pass. Implement this message to modify the result of the animation root motion on a state by state basis.
OnStateUpdateInvoked on each update frame except for the first and last frame. Implement this message to execute custom logic on a state by state basis.

Inherited Members

Properties

hideFlagsShould the object be hidden, saved with the Scene or modifiable by the user?
nameThe name of the object.

Public Methods

GetInstanceIDGets the instance ID of the object.
ToStringReturns the name of the object.

Static Methods

DestroyRemoves a GameObject, component or asset.
DestroyImmediateDestroys the object obj immediately. You are strongly recommended to use Destroy instead.
DontDestroyOnLoadDo not destroy the target Object when loading a new Scene.
FindAnyObjectByTypeRetrieves any active loaded object of Type type.
FindFirstObjectByTypeRetrieves the first active loaded object of Type type.
FindObjectsByTypeRetrieves a list of all loaded objects of Type type.
InstantiateClones the object original and returns the clone.
InstantiateAsyncCaptures a snapshot of the original object (that must be related to some GameObject) and returns the AsyncInstantiateOperation.
CreateInstanceCreates an instance of a scriptable object.

Operators

boolDoes the object exist?
operator !=Compares if two objects refer to a different object.
operator ==Compares two object references to see if they refer to the same object.

Messages

AwakeCalled when an instance of ScriptableObject is created.
OnDestroyThis function is called when the scriptable object will be destroyed.
OnDisableThis function is called when the scriptable object goes out of scope.
OnEnableThis function is called when the object is loaded.
OnValidateEditor-only function that Unity calls when the script is loaded or a value changes in the Inspector.
ResetReset to default values.