* delayed creation of TerrainQuad executorService unless absolutely needed

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@7823 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/terrain/com/jme3/terrain/geomipmap/TerrainQuad.java

@@ -105,8 +105,10 @@ public class TerrainQuad extends Node implements Terrain {
 
     private TerrainPicker picker;
 
+    protected ExecutorService executor;
 
-    protected ExecutorService executor = Executors.newSingleThreadExecutor(new ThreadFactory() {
+    protected ExecutorService createExecutorService() {
+        return Executors.newSingleThreadExecutor(new ThreadFactory() {
             public Thread newThread(Runnable r) {
                 Thread th = new Thread(r);
                 th.setName("jME Terrain Thread");
@@ -114,7 +116,7 @@ public class TerrainQuad extends Node implements Terrain {
                 return th;
             }
         });
-
+    }
 
     public TerrainQuad() {
         super("Terrain");
@@ -229,6 +231,9 @@ public class TerrainQuad extends Node implements Terrain {
             return; // we just want the root quad to perform this.
         }
 
+        if (executor == null)
+            executor = createExecutorService();
+        
         UpdateLOD updateLodThread = new UpdateLOD(locations);
         executor.execute(updateLodThread);
     }