BufferSystem

Buff可以理解成是一种技能，这种技能加持在一个游戏对象身上，增加这种Buff所特有的属性，包括持续时间，次数等，常用语游戏里面的技能加减血，加减速度等

1.所有Buffer的类型基类

========================================

using UnityEngine;
using System.Collections;
using System;

//所有Buffer的类型基类,抽象类可以包含抽象方法和普通方法，
//但是必须要在子类里实现所有基类里面的抽象方法
public abstract class BufferStateBase
{
    // 1.当前状态控制的游戏对象是谁
    public Transform CurrCtrl {
        get;
        set;
    }

    // 2.当前Buffer的类型 -> Buffer? Debuffer? PerBuffer? PerDeBuffer?
    public object CurrBufferType {
        get;
        set;
    }

    // 3.当前Buffer具体值 -> SpeedUp? Disarm?
    public object CurrBurrferState {
        get;
        set;
    }

    // 4.当前buffer的具体描述, 注意一个抽象方法，在继承它的子类里必须实现他一
    public abstract string CurrBufferInfo {
        get;
    }

    // 5.当前Buffer所接受的具体参数，注意是BufferArgs（里面的参数有一个脚本来定义）类型的
    public BufferArgs CurrArgs {
        set;
        get;
    }

    //一系列回调
    public abstract bool OnEnter ();

    public abstract bool OnUpdate ();

    public abstract bool OnExit ();
}

2.当前Buffer所具有的具体参数

using UnityEngine;
using System.Collections;

public class BufferArgs
{
    // 是否允许重复添加?
    // false: 不允许重复添加, 但是更新持续时间,意思是当添加一个Buffer时，
    //如果已经添加了相同的Buffer，那么就只会重新刷新持续时间，而不会重复添加
    // true: 允许重复添加, 两个相同的buffer同时发挥作用
    public bool m_addition = false;

    // 如果是周期性的buffer, 每一次间隔是多少?
    public float m_Timer;
    // 如果是按次数计量
    public int m_Times;
    // 能否被驱散
    public bool m_Dispel;
    // 持续时间
    public float m_ContinuousTime;
    // 是否结束
    public bool isOver = false;

    //其他一些可能用到的参数
    public float m_fValue1;
    public float m_fValue2;
    public float m_fValue3;
    public float m_fValue4;

    public string m_sValue1;
    public string m_sValue2;
    public string m_sValue3;
    public string m_sValue4;

    public bool m_bValue1;
    public bool m_bValue2;
    public bool m_bValue3;
    public bool m_bValue4;
}

3. 这个类中存放各种枚举的类型

public class BufferType
{
    // 正面buffer
    public enum Buffer
    {
        AllType,
        //加速的Buffer
        BufferSpeedUp,
        //无敌Buffer
        BufferInvincible,
    }

    // 负面buffer
    public enum DeBuffer
    {
        AllType,
        //减速的Buffer
        BufferSlowDown,
        //除装的Buffer
        BufferDisarm,
    }

    // 周期性的正面buffer
    public enum PerBuffer
    {
        AllType,
        //持续加血的Buffer
        BufferAddBlood,
        //持续加魔法值的Buffer
        BufferAddMagic,
    }

    // 周期性的负面buffer
    public enum PerDeBuffer
    {
        AllType,
        //持续减血的Buffer
        BufferCRBlood,
    }
}

4.加速的Buffer

using UnityEngine;
using System.Collections;

//继承自Buffer基类的，加速的Buffer
public class BufferSpeedUp : BufferStateBase
{
    #region implemented abstract members of BufferStateBase

    //重写基类中进入Buffer的回调
    public override bool OnEnter ()
    {
        UnityEngine.Debug.Log ("进入加速Buffer");
        return true;
    }

    //重写基类中Buffer持续的回调
    public override bool OnUpdate ()
    {
        //CurrArgs.m_ContinuousTime，表示buffer持续时间CurrArgs是BufferArgs类型的
        UnityEngine.Debug.Log ("持续在加速Buffer中, 剩余时间:" + CurrArgs.m_ContinuousTime);
        if ((CurrArgs.m_ContinuousTime -= Time.deltaTime) <= 0) {
            CurrArgs.isOver = true;        //表示会否结束，True表示结束
        }
        return true;
    }

    //重写离开Buffer的回调
    public override bool OnExit ()
    {
        UnityEngine.Debug.Log ("离开了加速Buffer");
        return true;
    }

    //当前Buffer的简述
    public override string CurrBufferInfo {
        get {
            return "这是加速Buffer, 提速为:" + CurrArgs.m_fValue1;
        }
    }

    #endregion
}

5.Buffer控制器

using UnityEngine;
using System.Collections.Generic;
using System;

//Buffer控制器
public class BufferMgr
{
    // 1.该控制器不需要挂载到游戏对象身上
    // 2.和人物控制不同, 不同的buffer之间可以同时工作
    // 3.所以我们需要一个容器, 里面存放所有的buffer状态
    // 4.我们在每一帧, 按照添加的顺序, 不停的调用每一个状态的OnUpdate方法
    // 5.根据状态的m_addition条件来判断是否更新buffer的持续时间

    // 公开的接口
    // 受到buffer系统影响的游戏对象
    public Transform CurrCtrl {
        get;
        set;
    }

    // 构造方法
    public BufferMgr (Transform trans)
    {
        CurrCtrl = trans;
    }

    // Buffer容器
    private List<BufferStateBase> m_bufferList = new List<BufferStateBase> ();

    // 以下方法是我们的设计, 面向用户的
    // 尽可能的全, 并且易于理解和使用

    // 1.添加一个新的Buffer(包括刷新或者重新添加)
    private BufferStateBase BufferCreate (object buffer, BufferArgs bufferArgs)
    {
        //直接创建BufferstateBase类型的变量，于BufferSpeedUp是一样的
        //Activator.CreateInstance创建一个实例
        BufferStateBase newBuffer = 
            Activator.CreateInstance (
                Type.GetType (buffer.ToString ())
            ) 
            as BufferStateBase;

        //具体参数赋值
        newBuffer.CurrArgs = bufferArgs;
        // 控制的游戏对象（前面定义的Buffer影响到的游戏对象）
        newBuffer.CurrCtrl = CurrCtrl;
        //当前Buffer的类型，负面Buffer还是正面Buffer
        newBuffer.CurrBufferType = buffer.GetType ();
        //当前Buffer的具体值
        newBuffer.CurrBurrferState = buffer;

        return newBuffer;
    }

    private void BufferAddBase (object buffer, BufferArgs bufferArgs)
    {
        // 实例化一个Buffer
        BufferStateBase newBuffer = BufferCreate (buffer, bufferArgs);
        // 判断该buffer是否应该添加到容器中
        if (newBuffer.CurrArgs.m_addition == true) {
            // 添加到容器中
            newBuffer.OnEnter ();
            m_bufferList.Add (newBuffer);
        } else {
            // 判断该状态在容器中是否存在
            if (BufferCheckExistsBase (buffer)) { // 存在, 更新作用时间
                //这样用到一个委托（一种缩写形式），在列表里找是否存在Buffer类型的Buffer，然后复制给oldBuffer
                BufferStateBase oldBuffer = m_bufferList.Find (delegate(BufferStateBase obj) {
                    return obj.CurrBurrferState.Equals (buffer);    
                });
                //如果oldBuffer不为空，表示容器中存在了于该Buffer相同的Buffer
                if (oldBuffer != null) {
                    //那么及更新一下作用时间，也就是重新赋一下值
                    oldBuffer.CurrArgs.m_ContinuousTime = newBuffer.CurrArgs.m_ContinuousTime;
                }
            } else { // 不存在, 直接添加进去
                // 添加到容器中
                newBuffer.OnEnter ();
                m_bufferList.Add (newBuffer);
            }
        }
    }

    public void BufferAdd (BufferType.Buffer buffer, BufferArgs bufferArgs)
    {
        // 根据buffer参数创建一个新的BufferStateBase对象
        BufferAddBase (buffer, bufferArgs);
    }

    public void BufferAdd (BufferType.DeBuffer buffer, BufferArgs bufferArgs)
    {
        BufferAddBase (buffer, bufferArgs);
    }

    public void BufferAdd (BufferType.PerBuffer buffer, BufferArgs bufferArgs)
    {
        BufferAddBase (buffer, bufferArgs);
    }

    public void BufferAdd (BufferType.PerDeBuffer buffer, BufferArgs bufferArgs)
    {
        BufferAddBase (buffer, bufferArgs);
    }

    // 2.移除某一种Buffer, 或者某一类Buffer
    private void BufferRemoveBase (object bufferType = null)
    {
        if (bufferType == null) {
            m_bufferList.RemoveAll (delegate(BufferStateBase obj) {
                return (obj.OnExit () || true);
            });
            return;
        }

        // 删除一类Buffer还是删除一个Buffer?
        if ((int)bufferType == 0) {
            m_bufferList.RemoveAll (delegate(BufferStateBase obj) {
                return obj.CurrBufferType.Equals (bufferType.GetType ()) && (obj.OnExit () || true);
            });
        } else {
            m_bufferList.RemoveAll (delegate(BufferStateBase obj) {
                return obj.CurrBurrferState.Equals (bufferType) && (obj.OnExit () || true);
            });
        }
    }

    public void BufferRemove (BufferType.Buffer buffer)
    {
        BufferRemoveBase (buffer);
    }

    public void BufferRemove (BufferType.DeBuffer buffer)
    {
        BufferRemoveBase (buffer);
    }

    public void BufferRemove (BufferType.PerBuffer buffer)
    {
        BufferRemoveBase (buffer);
    }

    public void BufferRemove (BufferType.PerDeBuffer buffer)
    {
        BufferRemoveBase (buffer);
    }

    public void BufferRemove ()
    {
        BufferRemoveBase ();
    }

    // 3.检查某个Buffer是否存在
    private bool BufferCheckExistsBase (object buffer)
    {
        BufferStateBase findBuffer = m_bufferList.Find (delegate(BufferStateBase obj) {
            return obj.CurrBurrferState.Equals (buffer);
        });

        //三目运算符，判断是否存在，存在返回Ture，不存在返回False
        return findBuffer == null ? false : true;
    }

    public bool BufferCheckExists (BufferType.Buffer buffer)
    {
        return BufferCheckExistsBase (buffer);
    }

    public bool BufferCheckExists (BufferType.DeBuffer buffer)
    {
        return BufferCheckExistsBase (buffer);
    }

    public bool BufferCheckExists (BufferType.PerBuffer buffer)
    {
        return BufferCheckExistsBase (buffer);
    }

    public bool BufferCheckExists (BufferType.PerDeBuffer buffer)
    {
        return BufferCheckExistsBase (buffer);
    }

    // 4.驱动OnUpdate的方法
    public void Updata ()
    {
        // 调用每个Buffer的update方法
        m_bufferList.Find (delegate(BufferStateBase obj) {
            return (obj.OnUpdate () || true);    
        });
        // 检查结束的Buffer, 然后移除之
        m_bufferList.RemoveAll (delegate(BufferStateBase obj) {
            return obj.CurrArgs.isOver == true && (obj.OnExit () || true);
        });
    }
}

6.Buffer管理，挂在游戏对象身上

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour
{

    public BufferMgr m_bufferMgr;        //接受一个Buffer控制器

    void Start ()
    {
        m_bufferMgr = new BufferMgr (transform);
    }

    void Update ()
    {
        //每帧调用依次Update
        m_bufferMgr.Updata ();

        if (Input.GetKeyDown (KeyCode.Alpha1)) {
            BufferArgs args = new BufferArgs ();
            args.m_fValue1 = 0.2f;
            args.m_addition = false;
            args.m_ContinuousTime = 3;
            m_bufferMgr.BufferAdd (BufferType.Buffer.BufferSpeedUp, args);        
        }
        if (Input.GetKeyDown (KeyCode.Alpha2)) {
            m_bufferMgr.BufferRemove (BufferType.Buffer.BufferSpeedUp);    
        }
        if (Input.GetKeyDown (KeyCode.Alpha3)) {
            m_bufferMgr.BufferRemove ();            
        }
    }
}