home.md

 ---
 title: Night of Horror
 ---
+
 # Game Design Document
 [TOC]
 
@@ -299,3 +300,54 @@ title: Night of Horror
       * Expand game content, and improve playability and diversity.
     + Specific implementation: 
       * Design unique levels on different floors, and add new puzzles, monster behaviors, or scene changes on each floor to bring fresh experiences to players.
+
+
+# Coding
+
+## State Machine
+'''
+public interface IState
+{
+    public void Enter();
+
+    public void Exit();
+
+    public void Update();
+
+    public void PhysicsUpdate();
+}
+~~~
+public abstract  class StateMachine
+{
+    protected IState currentState;
+
+    public void ChangeState(IState newState)
+    {
+        //currentState?.Exit();
+        if (currentState != null)
+        {
+            currentState.Exit();
+        }
+
+        currentState = newState;
+
+        currentState.Enter();
+    }
+
+    public void Update()
+    {
+        if (currentState != null)
+        {
+            currentState.Update();
+        }
+    }
+
+    public void PhysicsUpdate()
+    {
+        if (currentState != null)
+        {
+            currentState.PhysicsUpdate();
+        }
+    }
+}
+'''