daily update on 20230418 by nitload youmu.

rewrite of geometry is completed.
ready for release of ver0.1.0

源代码/StgSharp/Geometries/Point.cs

@@ -9,7 +9,7 @@ using System.Text;
 
 namespace StgSharp.Geometries
 {
-    public class Point: INode<Point>
+    public class Point : INode<Point>
     {
 
         internal vec3d _position;
@@ -24,7 +24,17 @@ namespace StgSharp.Geometries
             get { return this._position.Y; }
         }
 
-        public void Update() => new NotImplementedException();
+        internal readonly bool isVertex;
+
+        public bool IsVertex => isVertex;
+
+        /// <summary>
+        /// 刷新点的位置，即移动点。当该点是某个几何体的从动点时
+        /// （即点坐标由几何体其他点约束或点参数已经在创建几何体时定义）
+        /// 请不要再次进行定义，程序将自行忽略此处的代码。
+        /// </summary>
+        /// <param name="tick">当前游戏刻</param>
+        public virtual void Update(uint tick) {}
 
         public bool IsInGeometry(IPlainGeometry geo)
         {