增加SerieLabel的autoOffset参数设置是否自动判断上下偏移

Assets/XCharts/Runtime/Component/Sub/SerieLabel.cs

@@ -102,6 +102,7 @@ namespace XCharts
         [SerializeField] private float m_BorderWidth = 0.5f;
         [SerializeField] private Color m_BorderColor = Color.grey;
         [SerializeField] private string m_NumericFormatter = "";
+        [SerializeField] private bool m_AutoOffset = false;
 
         /// <summary>
         /// Whether the label is showed.
@@ -332,5 +333,13 @@ namespace XCharts
             get { return m_NumericFormatter; }
             set { if (PropertyUtility.SetClass(ref m_NumericFormatter, value)) SetComponentDirty(); }
         }
+        /// <summary>
+        /// 是否开启自动偏移。当开启时，Y的偏移会自动判断曲线的开口来决定向上还是向下偏移。
+        /// </summary>
+        public bool autoOffset
+        {
+            get { return m_AutoOffset; }
+            set { if (PropertyUtility.SetStruct(ref m_AutoOffset, value)) SetAllDirty(); }
+        }
     }
 }