代碼生成AnimatorController

0.出發點
現在的項目需要設置多套動畫組合，全部是由策划在XML文件中設置完成，如果完全的手動在AnimatorController中去做不但工作量大而且如果將來有配置修改了還要一個個去找到對應的自狀態機並且修改。因此就萌生了用代碼去生成狀態機的想法，而且在網上也有了很多的教程可以參考，只是每個項目都不同，且對於一些參數和屬性的設置也不盡相同，因此還是把自己的代碼進行一些修改后分享出來，基本上應該是包含了狀態機常用的功能。

1.數據來源

一個典型的XML文件

<?xml version="1.0" encoding="ISO-8859-1"?>
<config>
    <datas>
        <data INDEX="1" Clip1="jump" Clip1Count="1" Clip2="BackLeap" Clip2Count="2" Clip3="die" Clip3Count="1"></data>
        <data INDEX="2" Clip1="BackLeap" Clip1Count="3" Clip2="jump" Clip2Count="0" Clip3="jump" Clip3Count="0"></data>
        <data INDEX="3" Clip1="BackLeap" Clip1Count="1" Clip2="ForwardLeap" Clip2Count="1" Clip3="jump" Clip3Count="1"></data>
    </datas>
</config>            

2.動畫控制器中的主要元素 

2.1 Unity中editor的功能十分的強大，能夠加載項目中的各種資源，而AnimatorController就是其中之一。

2.2 一個AnimatorController的結構基本如下:

2.3 一些說明：

- AnimatorControllerLayer：一個AnimatorController由多個Layer組成，但是除了BaseLayer外其它的Layer並不主要負責動畫邏輯，而是多用於動畫遮罩。

- AnimatorControllerParameter：顧名思義是狀態機中使用的參數，這個參數可以在不同的Layer和子狀態機中使用。在代碼添加參數時會選擇參數類型，它是個枚舉`AnimatorControllerParameterType`。

- AnimatorStateMachine：動畫狀態機，核心邏輯實線層。在一個狀態機中可以有多個state，也可以有多個Sub AnimatorStateMachine。通過AddStateMachine方法來生成並添加子狀態機。

- AnimatorState：動畫狀態，也是這個系統中的基礎單元。其可以設定各種屬性，比較常用的是AnimationClip和Speed等。

- AnimatorStateTransition：也就是動畫轉換，其中可以設定觸發參數，而且其中還有一個很重要的東西就是動畫過度的設定。

 

3.完整代碼

using UnityEngine;
using System.Collections;
using UnityEditor;
using System;
using UnityEditor.Animations;
using System.IO;
using System.Xml;
using System.Text.RegularExpressions;
using System.Xml.Serialization;
using System.Collections.Generic;
using System.Linq;

//[CustomEditor(typeof(EditorTools))]
public class EditorTools : MonoBehaviour
{
    #region 創建動畫控制器

    /// <summary>
    ///  記錄上一個state，用於自狀態機中
    /// </summary>
    static AnimatorState lastAnimatorState = null;
    static string ParameterName;
    // 動畫片段
    static AnimationClip die;
    static AnimationClip jump;
    static AnimationClip BackLeap;
    static AnimationClip ForwardLeap;
    /// <summary>
    /// base layer AnimatorStateMachine
    /// </summary>
    static AnimatorStateMachine mainASM;
    static int stateHeight = 100;
    static int stateWidth = 220;

    /// <summary>
    /// 根據配置文件創建特技組
    /// </summary>
    [MenuItem ("Tools/CreateAnimatorState")]
    static void CreateAnimatorState ()
    {
        // 獲取動畫片段
        List<object> allAssets = new List<object> (AssetDatabase.LoadAllAssetsAtPath ("Assets/Charactors/player2.FBX"));
        var animationClips = allAssets.Where (o => o.GetType () == typeof(AnimationClip)).ToList ();
        foreach (var item in animationClips) {
            AnimationClip x = item as AnimationClip;
            switch (x.name) {
            case "die":
                die = x;
                break;
            case "jump":
                jump = x;
                break;
            case "BackLeap":
                BackLeap = x;
                break;
            case "ForwardLeap":
                ForwardLeap = x;
                break;
            default:
                break;
            }
        }

        // 當每個動畫是一個單獨的FBX文件中時可以用下面的方法來獲取
        //die = AssetDatabase.LoadAssetAtPath ("Assets/Charactors/player2.FBX", typeof(AnimationClip)) as AnimationClip;


        // 獲取狀態機
        AnimatorController animatorController = AssetDatabase.LoadAssetAtPath ("Assets/AnimatorController/demo.controller", typeof(AnimatorController)) as AnimatorController;
        AnimatorControllerLayer layer = animatorController.layers [0];
        mainASM = layer.stateMachine;

        // 獲取當前所有的參數
        AnimatorControllerParameter[] paras = animatorController.parameters;
        List<AnimatorControllerParameter> listParas = new List<AnimatorControllerParameter> (paras);

        // 刪除指定的參數
        var acps = listParas.Where (p => p.name.Contains ("GroupParameter")).ToArray ();
        foreach (AnimatorControllerParameter item in acps) {
            animatorController.RemoveParameter (item);
        }

        // 刪除指定的子狀態機
        ChildAnimatorStateMachine[] childASM = mainASM.stateMachines;
        List<ChildAnimatorStateMachine> listCASM = new List<ChildAnimatorStateMachine> (childASM);
        var casms = listCASM.Where (c => c.stateMachine.name.Contains ("Group")).ToArray ();
        foreach (ChildAnimatorStateMachine item in casms) {
            mainASM.RemoveStateMachine (item.stateMachine);
        }

        // 讀配置文件
        XmlConfig xc = ReadXml ();

        Vector3 startPos = mainASM.anyStatePosition;


        // 根據配置創建自狀態機
        for (int index = 0; index < xc.datas.Count; index++) {
            Data data = xc.datas [index];

            // 設置特技參數，
            ParameterName = "GroupParameter" + data.INDEX.ToString ();
            animatorController.AddParameter (ParameterName, AnimatorControllerParameterType.Trigger);

            // 創建子狀態機
            AnimatorStateMachine sub = AddSubStateMachine<AnimatorEvent> ("Group_" + data.INDEX, ParameterName, mainASM, startPos + new Vector3 (stateWidth * index, -stateHeight, 0));
            // 創建子狀態機中的state
            SetStateInSubMachine (sub, data);
            lastAnimatorState = null;
        }
    }

    /// <summary>
    ///  創建sub state machine用於放置特效組中的動畫
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="stateName"></param>
    /// <param name="sm"></param>
    /// <param name="position"></param>
    /// <param name="data"></param>
    /// <returns></returns>
    private static AnimatorStateMachine AddSubStateMachine<T> (string stateName, string para, AnimatorStateMachine sm, Vector3 position) where T : StateMachineBehaviour
    {
        AnimatorStateMachine sub = sm.AddStateMachine (stateName, position);
        sub.AddStateMachineBehaviour<T> ();
        AnimatorStateTransition transition = mainASM.defaultState.AddTransition (sub, false);
        transition.AddCondition (AnimatorConditionMode.If, 0, para);
        return sub;
    }

    /// <summary>
    ///  根據配置數據在子狀態機中創建state
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="subSM"></param>
    /// <param name="data"></param>
    private static void SetStateInSubMachine (AnimatorStateMachine subSM, Data data)
    {
        AnimatorState newState;
        string stateName;
        Vector3 pos;
        List<AnimationClip> acArray = new List<AnimationClip> ();
        SetAnimationClip (data.Clip1, data.Clip1Count, ref acArray);
        SetAnimationClip (data.Clip2, data.Clip2Count, ref acArray);
        SetAnimationClip (data.Clip3, data.Clip3Count, ref acArray);

        for (int x = 1; x <= acArray.Count; x++) {
            stateName = "GroupState_" + data.INDEX + "_" + x.ToString ();
            pos = subSM.entryPosition + new Vector3 (stateWidth, -stateHeight * x, 0);
            newState = AddState (stateName, subSM, pos, acArray [x - 1], x, acArray.Count);
            lastAnimatorState = newState;
        }
    }

    static void SetAnimationClip (string clipName, int count, ref List<AnimationClip> acArray)
    {
        for (int i = 0; i < count; i++) {
            if (clipName == die.name) {
                acArray.Add (die);
            }
            if (clipName == jump.name) {
                acArray.Add (jump);
            }
            if (clipName == BackLeap.name) {
                acArray.Add (BackLeap);
            }
            if (clipName == ForwardLeap.name) {
                acArray.Add (ForwardLeap);
            }
        }
    }

    static AnimatorState AddState<T> (string stateName, AnimatorStateMachine sm, float threshold, string parameter, Vector3 position,
                                      AnimationClip clip, bool first = false, bool last = false) where T : StateMachineBehaviour
    {
        AnimatorStateTransition animatorStateTransition;
        //  生成AnimatorState
        AnimatorState animatorState = sm.AddState (stateName, position);
        // 設置動畫片段
        animatorState.motion = clip;
        // 創建AnimatorStateTransition
        // entry連接到特技組的第一個動畫
        if (first) {
            animatorStateTransition = sm.AddAnyStateTransition (animatorState);
            animatorStateTransition.AddCondition (AnimatorConditionMode.Equals, threshold, parameter);
        }
        // 最后一個動畫連接到stand
        if (last) {
            animatorStateTransition = animatorState.AddTransition (mainASM.defaultState);
        }

        // 特技組內的連接創建
        if (!first && !last) {
            animatorStateTransition = animatorState.AddTransition (mainASM.defaultState);
        }

        animatorStateTransition = lastAnimatorState.AddTransition (animatorState, true);

        //AnimatorStateTransition 的設置
        animatorStateTransition.canTransitionToSelf = false;
        animatorState.AddStateMachineBehaviour<T> ();
        return animatorState;
    }

    static AnimatorState AddState (string stateName, AnimatorStateMachine sm, Vector3 position, AnimationClip clip, int index, int count)
    {
        AnimatorStateTransition animatorStateTransition = null;
        //  生成AnimatorState
        AnimatorState animatorState = sm.AddState (stateName, position);
        // 設置動畫片段
        animatorState.motion = clip;
        // 創建AnimatorStateTransition
        // AnyState連接到特技組的第一個動畫
        if (index == 1) {
            //animatorStateTransition = sm.AddAnyStateTransition(animatorState);
            //animatorStateTransition.canTransitionToSelf = false;
        }
        // 最后一個動畫連接到main animator machine的default state
        if (index == count) {
            animatorStateTransition = animatorState.AddTransition (mainASM.defaultState);
            animatorStateTransition.hasExitTime = true;
        }

        // 特技組內的連接創建
        if (lastAnimatorState != null) {
            animatorStateTransition = lastAnimatorState.AddTransition (animatorState, true);
        }

        return animatorState;
    }

    #endregion

    #region public method

    static XmlConfig ReadXml ()
    {
        //string xmlStr = File.ReadAllText(Application.dataPath.ToString() + "/StreamingAssets/XMLConfigFiles/Stunt.xml");
        //Debug.Log(xmlStr);
        //string objTxt = Regex.Replace(xmlStr, @"<!--[^-]*-->", string.Empty, RegexOptions.IgnoreCase);
        //Debug.Log(objTxt);
        return DeserializeFromXml<XmlConfig> (Application.dataPath.ToString () + "/StreamingAssets/XMLConfigFiles/data.xml");
    }

    /// <summary>
    /// 從某一XML文件反序列化到某一類型
    /// </summary>
    /// <param name="filePath">待反序列化的XML文件名稱</param>
    /// <param name="type">反序列化出的</param>
    /// <returns></returns>
    public static T DeserializeFromXml<T> (string filePath)
    {
        try {
            if (!System.IO.File.Exists (filePath))
                throw new ArgumentNullException (filePath + " not Exists");

            using (System.IO.StreamReader reader = new System.IO.StreamReader (filePath)) {
                System.Xml.Serialization.XmlSerializer xs = new System.Xml.Serialization.XmlSerializer (typeof(T));
                T ret = (T)xs.Deserialize (reader);
                return ret;
            }
        }
        catch (Exception ex) {
            return default(T);
        }
    }

    #endregion
}


#region 序列化需要的model
[XmlType (TypeName = "config")]
public class XmlConfig
{
    [XmlArray ("datas")]
    public List<Data> datas { get; set; }
}

[XmlType (TypeName = "data")]
public class Data
{
    [XmlAttribute]
    public int INDEX;
    [XmlAttribute]
    public string Clip1;
    [XmlAttribute]
    public int Clip1Count;
    [XmlAttribute]
    public string Clip2;
    [XmlAttribute]
    public int Clip2Count;
    [XmlAttribute]
    public string Clip3;
    [XmlAttribute]
    public int Clip3Count;
}

#endregion

 

4.最后的說明

- 其實整個過程基本就是讀取XML文件內容，然后按照第二部分中描述的結構來一點一點構建狀態機。

- 在設定具體屬性時需要按照具體情況來做。

- 有個天坑，就是如果在Base Layer界面多次點擊CreateAnimatorState按鈕時會出現Unity的crash，或者出現界面所有元素消失並報錯。我找了很多資料應該是UnityEditor的bug。有一個很簡單的解決辦法，就是創建一個新的Layer，切換到新Layer的界面，然后點擊CreateAnimatorState按鈕，再切回Base Layer，這樣就不會出錯了。