FSM有限状态机
一、设计思路
1.共同的状态父类，提供可重写的进入，保持，退出该状态的生命周期方法；
2.状态机，管理所有状态（增删查改），状态机运行方法（Run）；
3.在角色控制器中，实例化状态机，并初始化添加状态；
二、关键类
1.StateBase
给物体所有状态提供的基类，所有状态比较继承这个基类，并且重写生命周期的方法；
泛型T为角色控制类；
字段：
public int stateID; //状态ID，string也可
public T owner; //角色的实例
生命周期：
public abstract void OnEnter(params object[] args); //进入状态调用
public abstract void OnStay(params object[] args); //保持状态调用
public abstract void OnExit(params object[] args); //退出状态调用
完整代码：
public abstract class StateBase<T>
{
//给每个状态设置一个ID
public int stateID;
public T owner; //拥有者(范型)
public StateBase(int id,T o)
{
this.stateID = id;
owner = o;
}
//给子类提供方法
public abstract void OnEnter(params object[] args);
public abstract void OnStay(params object[] args);
public abstract void OnExit(params object[] args);
}
2.StateMachine
private Dictionary<int, StateBase<T>> FSMActDic; //存所有状态的字典
private int curState; //当前状态
public int nextState = 0; //下一个状态
关键方法：
切换状态时，调用当前方法的退出OnExit()后，继续调用下一个方法的进入OnEnter()；
其他时候调用当前方法的OnStay()；
public void FSMRun()
{
FSMActDic[curState].OnStay();
if (nextState != 0 && nextState != curState)
{
FSMActDic[curState].OnExit();
curState = nextState;
FSMActDic[curState].OnEnter();
nextState = 0;
}
}
完整代码：
public class FSM<T>
{
private Dictionary<int, StateBase<T>> FSMActDic;
private int curState;
public int nextState = 0;
private void SwitchState()
{
if (nextState != 0 && nextState != curState)
{
FSMActDic[curState].OnExit();
curState = nextState;
FSMActDic[curState].OnEnter();
nextState = 0;
}
}
public FSM(int id)
{
curState = id;
FSMActDic = new Dictionary<int, StateBase<T>>();
}
//增
public void AddState(int id, StateBase<T> state)
{
if(FSMActDic.ContainsKey(id))
return;
FSMActDic.Add(id, state);
}
//删
public void RemoveSatate(int id)
{
if (FSMActDic.ContainsKey(id))
FSMActDic.Remove(id);
}
//获取
public StateBase<T> GetState(int id)
{
if (!FSMActDic.ContainsKey(id))
return null;
return FSMActDic[id];
}
public void FSMRun()
{
FSMActDic[curState].OnStay();
SwitchState();
}
}
三、测试类
1.PlayerControl
实例状态机，添加几个状态，测试效果；这里我只做了简单的移动；
完整代码：
public class PlayerControl : MonoBehaviour
{
public enum PlayerState
{
none = 0,
idle,
move,
jump,
}
private FSM<PlayerControl> mPlayerFSM;
public PlayerState mState;
public Animator mAnimator;
public float mSpeed;
public Vector3 moveDir;
private void InitFSM()
{
mPlayerFSM.AddState((int) PlayerState.idle, new ActIdle((int) PlayerState.idle, this));
mPlayerFSM.AddState((int) PlayerState.move, new ActMove((int) PlayerState.move, this));
mPlayerFSM.AddState((int) PlayerState.jump, new ActScream((int) PlayerState.jump, this));
}
void Start()
{
mAnimator = GetComponentInChildren<Animator>();
mSpeed = 10;
mPlayerFSM = new FSM<PlayerControl>((int) PlayerState.idle);
InitFSM();
mState = PlayerState.idle;
}
void Update()
{
mPlayerFSM.FSMRun();
SwitchState();
mPlayerFSM.nextState = (int)mState;
}
private void SwitchState()
{
if (Input.GetAxis("Horizontal") > 0 && Input.GetAxis("Vertical") == 0)
{
moveDir = transform.right;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") < 0 && Input.GetAxis("Vertical") == 0)
{
moveDir = -transform.right;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") > 0 && Input.GetAxis("Vertical") < 0)
{
moveDir = transform.right - transform.forward;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") < 0 && Input.GetAxis("Vertical") < 0)
{
moveDir = -transform.right - transform.forward;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") > 0 && Input.GetAxis("Vertical") > 0)
{
moveDir = transform.right + transform.forward;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") < 0 && Input.GetAxis("Vertical") > 0)
{
moveDir = -transform.right + transform.forward;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") == 0 && Input.GetAxis("Vertical") < 0)
{
moveDir = -transform.forward;
mState = PlayerState.move;
}
else if (Input.GetAxis("Horizontal") == 0 && Input.GetAxis("Vertical") > 0)
{
moveDir = transform.forward;
mState = PlayerState.move;
}
if (Mathf.Abs(Input.GetAxis("Horizontal")) < 0.1f && Mathf.Abs(Input.GetAxis("Vertical")) < 0.1f)
mState = PlayerControl.PlayerState.idle;
if (Input.GetAxis("Jump") != 0)
{
mState = PlayerState.jump;
}
}
}
2.行为类
设置的移动，待机，吼叫三个行为类；
代码展示：
public class ActMove : StateBase<PlayerControl>
{
public ActMove(int id, PlayerControl t) : base(id, t)
{
}
//给子类提供方法
public override void OnEnter(params object[] args)
{
}
public override void OnStay(params object[] args)
{
owner.mAnimator.Play("Walk");
owner.transform.position += owner.moveDir * Time.deltaTime * owner.mSpeed;
}
public override void OnExit(params object[] args)
{
}
}
四、Demo展示
以上是我对FSM的总结，如果有更好的意见，欢迎给作者评论留言；
