refactor simulator State outside of Simulation

the contents of `State` concern the graphical rendering/playing of
the simulation and are not endogenous to the Simulation itself

Main.cs

@@ -3,20 +3,22 @@
 
 public class Main : MonoBehaviour {
 
-    private float elaspedTime = 0;
-
-    void Start () {
+    private void Start () {
         Simulation.Init();
         Simulation.Render();
     }
 
-    void Update () {
-        elaspedTime += Time.deltaTime;
-        float secondsPerStep = 1.0f / Simulation.Parameters.STEPS_PER_SECOND;
-        for ( int i = (int) ( this.elaspedTime / secondsPerStep ) ; i > 0 ; i-- ) {
+    private void Update () {
+        if ( State.PAUSED ) {
+            return;
+        }
+        State.DELTA_TIME += Time.deltaTime;
+        float secondsPerStep = 1.0f / State.STEPS_PER_SECOND;
+        for ( int i = (int) ( State.DELTA_TIME / secondsPerStep ) ; i > 0 ; i-- ) {
+            State.DELTA_TIME -= secondsPerStep;
             Simulation.Step();
             Simulation.Render();
-            this.elaspedTime -= secondsPerStep;
         }
     }
+
 }

Simulation.cs

@@ -6,7 +6,6 @@
 public class Simulation {
 
     public static class Parameters {
-        public static float STEPS_PER_SECOND = 4;
         public static int NUMBER_OF_AGENTS = 400;
         public static int SUGAR_GROWTH_RATE = 1;
         public static class Endowment {

State.cs

@@ -0,0 +1,8 @@
+
+public class State {
+
+    public static float DELTA_TIME = 0;
+    public static bool PAUSED = true;
+    public static int STEPS_PER_SECOND = 4;
+
+}