Unity 游戏框架搭建 (四) 简易有限状态机

来源：互联网发布：linux进去编辑模式编辑：程序博客网时间：2024/05/16 06:37

为什么用有限状态机?

之前做过一款跑酷游戏,跑酷角色有很多状态:跑、跳、二段跳、死亡等等。一开始是使用if/switch来切换状态,但是每次角色添加一个状态（提前没规划好),所有状态处理相关的代码就会指数级增长,那样就会嗅出代码的坏味道了。在这种处理状态并且状态数量不是特别多的情况下,自然就想到了引入状态机。

优点:

1.使代码整洁,状态容易扩展和管理。

2.可复用。

3.还没想到.....

缺点:

1.也没想到......

什么是有限状态机?

解释不清楚,看了下百度百科。反正是一种数据结构,一个解决问题的工具。

从百度百科可以看到,有限状态机最最最基础的概念有两个:状态和转移。

从刚才跑酷的例子来讲,跑、跳、二段跳等这些就是角色的状态。

如图所示:

主角从跑状态切换到跳状态,从跳状态切换到二段跳状态,这里的切换就是指状态的转移。状态的转移是有条件的,比如主角从跑状态不可以直接切换到二段跳状态。但是可以从二段跳状态切换到跑状态。

另外,一个基本的状态有:进入状态、退出状态、接收输入、转移状态等动作。但是仅仅作为跑酷的角色的状态管理来说,只需要转移状态就足够了。有兴趣的同学可以自行扩展。

如何实现?

恰好之前看到过一个还算简易的实现(简易就是指我能看得懂- -,希望大家也是),原版是用lua实现的,我的跑酷游戏是用C#实现的,所以直接贴出C#代码。

[C#] 纯文本查看复制代码

?
 
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
usingUnityEngine;  
usingSystem.Collections;  
usingSystem.Collections.Generic;  
publicclass FSM {  
    // 定义函数指针类型
    publicdelegate void FSMTranslationCallfunc();    /// <summary>
    /// 状态类
    /// </summary>
    publicclass FSMState
    {
        publicstring name;
 
        publicFSMState(stringname)
        {
            this.name = name;
        }
        /// <summary>
        /// 存储事件对应的条转
        /// </summary>
        publicDictionary <string,FSMTranslation> TranslationDict = newDictionary<string,FSMTranslation>();
    }
    /// <summary>
    /// 跳转类
    /// </summary>
    publicclass FSMTranslation
    {
        publicFSMState fromState;
        publicstring name;
        publicFSMState toState;
        publicFSMTranslationCallfunc callfunc; // 回调函数
 
        publicFSMTranslation(FSMState fromState,stringname, FSMState toState,FSMTranslationCallfunc callfunc)
        {
            this.fromState = fromState;
            this.toState   = toState;
            this.name = name;
            this.callfunc = callfunc;
        }
    }
    // 当前状态
    privateFSMState mCurState;
 
    Dictionary <string,FSMState> StateDict = newDictionary<string,FSMState>();
    /// <summary>
    /// 添加状态
    /// </summary>
    /// <param name="state">State.</param>
    publicvoid AddState(FSMState state)
    {
        StateDict [state.name] = state;
    }
    /// <summary>
    /// 添加条转
    /// </summary>
    /// <param name="translation">Translation.</param>
    publicvoid AddTranslation(FSMTranslation translation)
    {
        StateDict [translation.fromState.name].TranslationDict [translation.name] = translation;
    }
    /// <summary>
    /// 启动状态机
    /// </summary>
    /// <param name="state">State.</param>
    publicvoid Start(FSMState state)
    {
        mCurState = state;
    }
    /// <summary>
    /// 处理事件
    /// </summary>
    /// <param name="name">Name.</param>
    publicvoid HandleEvent(stringname)
    {
        if(mCurState != null&& mCurState.TranslationDict.ContainsKey(name)) {
            Debug.LogWarning ("fromState:"+ mCurState.name);
 
            mCurState.TranslationDict [name].callfunc ();
            mCurState = mCurState.TranslationDict [name].toState;
 
 
            Debug.LogWarning ("toState:"+ mCurState.name);
        }
    }
}

测试代码(需自行修改):

[C#] 纯文本查看复制代码

?
 
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
// 创建状态
FSM.FSMState idleState = newFSM.FSMState("idle");     //        Idle,               闲置
FSM.FSMState runState  = newFSM.FSMState("run");    //        Run,                跑
FSM.FSMState jumpState = newFSM.FSMState("jump");//        Jump,               一段跳
FSM.FSMState doubleJumpState = newFSM.FSMState("double_jump"); //        DoubleJump,         二段跳
FSM.FSMState dieState  = newFSM.FSMState("die");  //        Die,                挂彩
// 创建跳转
FSM.FSMTranslation touchTranslation1 = newFSM.FSMTranslation(runState,"touch_down",jumpState,Jump);
FSM.FSMTranslation touchTranslation2 = newFSM.FSMTranslation(jumpState,"touch_down",doubleJumpState,DoubleJump);
 
FSM.FSMTranslation landTranslation1 = newFSM.FSMTranslation(jumpState,"land",runState,Run);
FSM.FSMTranslation landTranslation2 = newFSM.FSMTranslation(doubleJumpState,"land",runState,Run);
 
// 添加状态
PlayerModel.Instance ().fsm.AddState (idleState);
PlayerModel.Instance ().fsm.AddState (runState);
PlayerModel.Instance ().fsm.AddState (jumpState);
PlayerModel.Instance ().fsm.AddState (doubleJumpState);
PlayerModel.Instance ().fsm.AddState (dieState);
 
// 添加跳转
PlayerModel.Instance ().fsm.AddTranslation (touchTranslation1);
PlayerModel.Instance ().fsm.AddTranslation (touchTranslation2);
PlayerModel.Instance ().fsm.AddTranslation (landTranslation1);
PlayerModel.Instance ().fsm.AddTranslation (landTranslation2);
 
PlayerModel.Instance ().fsm.Start (runState);[mw_shl_code=csharp,true]       // 创建状态
FSM.FSMState idleState = newFSM.FSMState("idle");
FSM.FSMState runState  = newFSM.FSMState("run");
FSM.FSMState jumpState = newFSM.FSMState("jump");
FSM.FSMState doubleJumpState = newFSM.FSMState("double_jump");
FSM.FSMState dieState  = newFSM.FSMState("die");
// 创建跳转
FSM.FSMTranslation touchTranslation1 = newFSM.FSMTranslation(runState,"touch_down",jumpState,Jump);
FSM.FSMTranslation touchTranslation2 = newFSM.FSMTranslation(jumpState,"touch_down",doubleJumpState,DoubleJump);
 
FSM.FSMTranslation landTranslation1 = newFSM.FSMTranslation(jumpState,"land",runState,Run);
FSM.FSMTranslation landTranslation2 = newFSM.FSMTranslation(doubleJumpState,"land",runState,Run);
 
// 添加状态
PlayerModel.Instance ().fsm.AddState (idleState);
PlayerModel.Instance ().fsm.AddState (runState);
PlayerModel.Instance ().fsm.AddState (jumpState);
PlayerModel.Instance ().fsm.AddState (doubleJumpState);
PlayerModel.Instance ().fsm.AddState (dieState);
 
// 添加跳转
PlayerModel.Instance ().fsm.AddTranslation (touchTranslation1);
PlayerModel.Instance ().fsm.AddTranslation (touchTranslation2);
PlayerModel.Instance ().fsm.AddTranslation (landTranslation1);
PlayerModel.Instance ().fsm.AddTranslation (landTranslation2);
 
PlayerModel.Instance ().fsm.Start (runState);

贴上代码地址址:https://github.com/liangxiegame/QFramework/blob/master/Script/DesignPattern/QFSM.cs

就这些,想要进一步扩展的话,可以给FSMState类添加EnterCallback和ExitCallback等委托,然后在FSM的HandleEvent方法中进行调用。当时对跑酷的项目来说够用了,接没继续扩展了,我好懒- -,懒的借口是:没有最好的设计,只有最适合的设计,233333。

附:[我的框架地址](https://github.com/liangxiegame/QFramework)

转载请注明地址:[凉鞋的笔记](http://liangxiegame.com/)

状态机 unity;unity 框架搭建;unity 状态机;unity中的状态机;unity搭建框架

0 0