游戏开发之Unity学习(十)——给游戏添加智能，牧师与魔鬼（智能版）

这次是在之前的博客的基础上，给游戏添加游戏智能。

考虑使用广度优先搜索算法来寻找最佳路径。

演示视频

实现效果如下：

游戏状态图的考虑

这个游戏的不同状态包括以下几个方面：
1. 河两岸的牧师与魔鬼数：public int[] currentStatus;//该数组长度为4
2. 船在哪一边的岸旁：public BoatLocation boatLocation;
3. 那些对象是要上船的：public PeopleOnBoat peopleOnBoat;
4. 之前的状态是什么：public status prev;

因此，定义状态类：

public enum PeopleOnBoat {FAILED, P, D, PP, DD, PD }
public enum BoatLocation { Left, Right }

public class status
{
    public int[] currentStatus;
    public PeopleOnBoat peopleOnBoat;
    public BoatLocation boatLocation;
    public status prev;

    public status(int startPriestCount,int startDevilCount,int endPriestCount,int endDevilCount, BoatLocation boatLocation = BoatLocation.Left, PeopleOnBoat peopleOnBoat = PeopleOnBoat.FAILED, status prevStatus = null)
    {
        currentStatus = new int[4];
        currentStatus[0] = startPriestCount;
        currentStatus[1] = startDevilCount;
        currentStatus[2] = endPriestCount;
        currentStatus[3] = endDevilCount;
        this.peopleOnBoat = peopleOnBoat;
        this.boatLocation = boatLocation;
        prev = prevStatus;
    }
    public bool Equals(status cStatus)
    {
        return currentStatus.Equals(cStatus.currentStatus);
    }
}

游戏智能的实现

使用广度优先搜索算法，首先要明确起始状态和最终状态。

1.首先考虑那种情况下，游戏失败。

private bool Check(status cStatus)
{
    return (cStatus.currentStatus[0] >= cStatus.currentStatus[1] || cStatus.currentStatus[0] == 0) &&
        (cStatus.currentStatus[2] >= cStatus.currentStatus[3] || cStatus.currentStatus[2] == 0);
}

2.使用广度优先搜索算法,因为起始状态不同，所以需要给出相应的起始状态：

private PeopleOnBoat BFSeach(status sStatus)

具体实现：

private PeopleOnBoat BFSeach(status sStatus)
{
    Queue queue = new Queue();
    queue.Enqueue(sStatus);

    status cStatus;

    while (queue.Count != 0)
    {
        cStatus = queue.Dequeue();
        status nextStatus;
        if (cStatus.currentStatus[2] + cStatus.currentStatus[3] == 6)
        {
            while(cStatus.prev != null && cStatus.prev.prev != null)
            {
                cStatus = cStatus.prev;
            }
            Debug.Log(cStatus.peopleOnBoat);
            return cStatus.peopleOnBoat;
        }

        if(cStatus.boatLocation == BoatLocation.Left)
        {
            if(cStatus.currentStatus[0] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0] - 1, cStatus.currentStatus[1],
                     cStatus.currentStatus[2] + 1, cStatus.currentStatus[3], BoatLocation.Right, PeopleOnBoat.P, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if(cStatus.currentStatus[0] > 1)
            {
                nextStatus = new status(cStatus.currentStatus[0] - 2, cStatus.currentStatus[1],
                    cStatus.currentStatus[2] + 2, cStatus.currentStatus[3], BoatLocation.Right, PeopleOnBoat.PP, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[1] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0], cStatus.currentStatus[1] - 1,
                    cStatus.currentStatus[2], cStatus.currentStatus[3] + 1, BoatLocation.Right, PeopleOnBoat.D, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[1] > 1)
            {
                nextStatus = new status(cStatus.currentStatus[0], cStatus.currentStatus[1] - 2,
                    cStatus.currentStatus[2], cStatus.currentStatus[3] + 2, BoatLocation.Right, PeopleOnBoat.DD, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[0] > 0 && cStatus.currentStatus[1] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0] - 1, cStatus.currentStatus[1] - 1,
                    cStatus.currentStatus[2] + 1, cStatus.currentStatus[3] + 1, BoatLocation.Right, PeopleOnBoat.PD, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
        }
        else
        {
            if (cStatus.currentStatus[2] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0] + 1, cStatus.currentStatus[1],
                    cStatus.currentStatus[2] - 1, cStatus.currentStatus[3], BoatLocation.Left, PeopleOnBoat.P, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[2] > 1)
            {
                nextStatus = new status(cStatus.currentStatus[0] + 2, cStatus.currentStatus[1],
                    cStatus.currentStatus[2] - 2, cStatus.currentStatus[3], BoatLocation.Left, PeopleOnBoat.PP, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[3] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0], cStatus.currentStatus[1] + 1,
                    cStatus.currentStatus[2], cStatus.currentStatus[3] - 1, BoatLocation.Left, PeopleOnBoat.D, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[3] > 1)
            {
                nextStatus = new status(cStatus.currentStatus[0] - 1, cStatus.currentStatus[1] + 2,
                    cStatus.currentStatus[2], cStatus.currentStatus[3] - 2, BoatLocation.Left, PeopleOnBoat.DD, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
            if (cStatus.currentStatus[2] > 0 && cStatus.currentStatus[3] > 0)
            {
                nextStatus = new status(cStatus.currentStatus[0] + 1, cStatus.currentStatus[1] + 1,
                    cStatus.currentStatus[2] - 1, cStatus.currentStatus[3] - 1, BoatLocation.Left, PeopleOnBoat.PD, cStatus);
                if (Check(nextStatus)) queue.Enqueue(nextStatus);
            }
        }
    }

    return PeopleOnBoat.FAILED;
}

3.在游戏中嵌入智能，是的游戏可以应用上面的只能，即 AI.Run。

public bool Run()
{
    FirstSceneController action = SSDirector.getInstance().currentSceneController as FirstSceneController;
    if (action.onBoatDevil.Count + action.onBoatPriest.Count == 0)
    {
        BoatLocation location = action.boat.transform.position.x < 0 ? BoatLocation.Left : BoatLocation.Right;
        status cStatus = new status(action.startPriest.Count, action.startDevil.Count, action.endPriest.Count, action.endDevil.Count, location);
        PeopleOnBoat peopleOnBoat = BFSeach(cStatus);
        if (location == BoatLocation.Left)
        {
            if (peopleOnBoat == PeopleOnBoat.P)
            {
                action.actionManager.OnBoat(action.startPriest[0],action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.PP)
            {
                action.actionManager.OnBoat(action.startPriest[0], action.actionManager);
                action.actionManager.OnBoat(action.startPriest[action.startPriest.Count - 1], action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.D)
            {
                action.actionManager.OnBoat(action.startDevil[0], action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.DD)
            {
                action.actionManager.OnBoat(action.startDevil[0], action.actionManager);
                action.actionManager.OnBoat(action.startDevil[action.startDevil.Count - 1], action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.PD)
            {
                action.actionManager.OnBoat(action.startDevil[0], action.actionManager);
                action.actionManager.OnBoat(action.startPriest[0], action.actionManager);
            }
            else return false;
        }
        else
        {
            if (peopleOnBoat == PeopleOnBoat.P)
            {
                action.actionManager.OnBoat(action.endPriest[0],action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.PP)
            {
                action.actionManager.OnBoat(action.endPriest[0],action.actionManager);
                action.actionManager.OnBoat(action.endPriest[action.endPriest.Count - 1],action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.D)
            {
                action.actionManager.OnBoat(action.endDevil[0],action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.DD)
            {
                action.actionManager.OnBoat(action.endDevil[0],action.actionManager);
                action.actionManager.OnBoat(action.endDevil[action.endDevil.Count - 1],action.actionManager);
            }
            else if (peopleOnBoat == PeopleOnBoat.PD)
            {
                action.actionManager.OnBoat(action.endDevil[0],action.actionManager);
                action.actionManager.OnBoat(action.endPriest[0],action.actionManager);
            }
            else return false;
        }
    }
    else if (action.actionManager.moveToAction == null || !action.actionManager.moveToAction.enable)
    {
        action.actionManager.MoveBoat(action.boat,action.actionManager);
    }

    return true;
}

4.UserGUI类中添加help 按钮。action.flag 确保游戏结束后，按钮无效。

if(action.flag == 0 && GUI.Button(new Rect(0, 240, 80, 60), "Help")) {
    AI aI = new AI();
    aI.Run();
}

更多详细代码请戳：传送门