fixed collisiongroup check on grid change

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@7720 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

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

@@ -29,7 +29,6 @@ import com.jme3.terrain.heightmap.HeightMapGrid;
 public class TerrainGrid extends TerrainQuad {
 
     private static final Logger log = Logger.getLogger(TerrainGrid.class.getCanonicalName());
-    
     private Vector3f currentCell;
     private int quarterSize;
     private int quadSize;
@@ -249,10 +248,11 @@ public class TerrainGrid extends TerrainQuad {
         this.updateModelBound();
 
         if (control != null) {
-            int currentCollisionGroup = control.getCollideWithGroups();
+            int collisionGroupsCollideWith = control.getCollideWithGroups();
+            int collisionGroups = control.getCollisionGroup();
             control = new RigidBodyControl(new HeightfieldCollisionShape(getHeightMap(), getLocalScale()), 0);
-            control.setCcdMotionThreshold(0.5f);
+            control.setCollideWithGroups(collisionGroupsCollideWith);
-            control.setCollisionGroup(currentCollisionGroup);
+            control.setCollisionGroup(collisionGroups);
             this.addControl(control);
             space.add(this);
         }