1.修复一些错误2.准备专门提供基于距离的spline3.tracydll存在崩溃问题

Assets/Scripts/Framework/DDT.cs

@@ -2,6 +2,7 @@ using System.Collections;
 using System.Collections.Generic;
 using Convention;
 using UnityEngine;
+using System;
 
 namespace Demo.Game
 {
@@ -29,9 +30,23 @@ namespace Demo.Game
         [Convention.RScript.Variable.Attr.Method]
         public float At(int index)
         {
+            if (index < 0)
+                index = Datas.Count + index;
+            if (index < 0 || index >= Datas.Count)
+                throw new IndexOutOfRangeException($"{index} is out of [0, {Datas.Count})");
             return Datas[index];
         }
 
+        /// <summary>
+        /// <20><>ȡ<EFBFBD><C8A1><EFBFBD>ݳ<EFBFBD><DDB3><EFBFBD>
+        /// </summary>
+        /// <returns></returns>
+        [Convention.RScript.Variable.Attr.Method]
+        public int GetCount()
+        {
+            return Datas.Count;
+        }
+
         public IEnumerator<float> GetEnumerator()
         {
             return ((IEnumerable<float>)Datas).GetEnumerator();