Some work on scoring for MCTS

src/battle/controllers/Piers/MCTSNode.java

 package battle.controllers.Piers;
 
 import asteroids.Action;
-import asteroids.GameState;
+import battle.SimpleBattle;
 
 import java.util.Random;
 
@@ -19,17 +19,21 @@ public class MCTSNode {
     private MCTSNode parent;
     private MCTSNode[] children;
     private int numberOfChildrenExpanded;
+    private boolean ourNode;
 
     private int currentDepth;
+    private int playerID;
 
     private double totalValue;
     private int numberOfVisits = 1;
 
     private double explorationConstant;
 
-    public MCTSNode(double explorationConstant) {
+    public MCTSNode(double explorationConstant, int playerID) {
         this.explorationConstant = explorationConstant;
         currentDepth = 0;
+        this.playerID = playerID;
+        ourNode = true;
     }
 
     private MCTSNode(MCTSNode parent, Action moveToThisState) {
@@ -38,6 +42,8 @@ public class MCTSNode {
         this.parent = parent;
         this.children = new MCTSNode[MCTSNode.allActions.length];
         this.currentDepth = parent.currentDepth + 1;
+        this.playerID = parent.playerID;
+        this.ourNode = parent.ourNode;
     }
 
     public static void setAllActions() {
@@ -53,7 +59,7 @@ public class MCTSNode {
         }
     }
 
-    public MCTSNode select(GameState state, int maxDepth) {
+    public MCTSNode select(SimpleBattle state, int maxDepth) {
         MCTSNode current = this;
         while (current.currentDepth <= maxDepth) {
             if (current.fullyExpanded()) {
@@ -93,17 +99,22 @@ public class MCTSNode {
                 (explorationConstant * (Math.sqrt(Math.log(parent.numberOfVisits) / numberOfVisits)));
     }
 
-    public void updateValues(double value) {
+    public void updateValues(double value, double enemyScore) {
         MCTSNode current = this;
         while (current.parent != null) {
             current.numberOfVisits++;
-            // todo work out scoring system.
+            current.totalValue += (current.ourNode) ? value : enemyScore;
             current = current.parent;
         }
     }
 
-    public double rollout(GameState state) {
-        return 0.0d;
+    public double[] rollout(SimpleBattle state) {
+        while (!state.isGameOver()) {
+            Action first = allActions[random.nextInt(allActions.length)];
+            Action second = allActions[random.nextInt(allActions.length)];
+            state.update(first, second);
+        }
+        return new double[]{state.getPoints(playerID), state.getPoints((playerID == 1) ? 0 : 1)};
     }
 
     public Action getBestAction() {

src/battle/controllers/Piers/PiersBattleTest.java

+package battle.controllers.Piers;
+
+/**
+ * Created by pwillic on 12/06/2015.
+ */
+public class PiersBattleTest {
+
+    public static void main(String[] args) {
+
+    }
+}

src/battle/controllers/Piers/PiersMCTS.java

@@ -11,7 +11,7 @@ public class PiersMCTS implements BattleController {
 
     @Override
     public Action getAction(SimpleBattle gameStateCopy, int playerId) {
-        MCTSNode root = new MCTSNode(2.0);
+        MCTSNode root = new MCTSNode(2.0, playerId);
 
         return null;
     }