remove unneeded timeInState calc & redundant "string?" annotation

Shared/FSM.cs

@@ -4,11 +4,12 @@ using System.Collections.Generic;
 namespace SemiColinGames {
   public interface IState<T> {
     public void Enter();
-    public string? Update(T obj, float modelTime, World world);
+
+    // Returns the name of the new state, or null if we should stay in the same state.
+    public string Update(T obj, float modelTime, World world);
   }
 
   public class FSM<T> {
-    float timeInState = 0f;
     Dictionary<string, IState<T>> states;
     IState<T> state;
 
@@ -21,16 +22,13 @@ namespace SemiColinGames {
     public string StateName { get; private set; }
 
     public void Update(T obj, float modelTime, World world) {
-      timeInState += modelTime;
-      string? newState = state.Update(obj, modelTime, world);
+      string newState = state.Update(obj, modelTime, world);
       if (newState != null) {
         Transition(newState);
       }
     }
 
     void Transition(string state) {
-      Debug.WriteLine("{0} -> {1} @ {2}", StateName, state, timeInState);
-      timeInState = 0f;
       StateName = state;
       IState<T> newState = states[state];
       this.state = newState;

Shared/NPC.cs

@@ -10,7 +10,7 @@ namespace SemiColinGames {
       timeInState = 0;
     }
 
-    public string? Update(NPC npc, float modelTime, World world) {
+    public string Update(NPC npc, float modelTime, World world) {
       timeInState += modelTime;
       if (timeInState > 1.0f) {
         npc.Facing *= -1;
@@ -23,7 +23,7 @@ namespace SemiColinGames {
   class RunState : IState<NPC> {
     public void Enter() {}
 
-    public string? Update(NPC npc, float modelTime, World world) {
+    public string Update(NPC npc, float modelTime, World world) {
       int moveSpeed = 120;
       int desiredX = npc.Position.X + (int) (moveSpeed * npc.Facing * modelTime);
       // TODO: define the box modularly & correctly.