Add getSpatial to GhostControl, RigidBodyControl, AbstractPhysicsCont… (#1041)

* Add getSpatial to GhostControl, RigidBodyControl, AbstractPhysicsControl and CharacterControl. Fix issue 1008

* Fix doc: control is attached to spatial. Not the other way around.

* Update doc: Clarify what getSpatial returns

jme3-bullet/src/common/java/com/jme3/bullet/control/AbstractPhysicsControl.java

@@ -246,6 +246,13 @@ public abstract class AbstractPhysicsControl implements PhysicsControl, JmeClone
         setPhysicsRotation(getSpatialRotation());
     }
 
+    /**
+     * @return returns the spatial the control is added to, or null if the control is not attached to a spatial yet.
+     */
+    public Spatial getSpatial(){
+        return this.spatial;
+    }
+
     /**
      * Enable or disable this control.
      * <p>

jme3-bullet/src/common/java/com/jme3/bullet/control/CharacterControl.java

@@ -129,6 +129,13 @@ public class CharacterControl extends PhysicsCharacter implements PhysicsControl
         setPhysicsLocation(getSpatialTranslation());
     }
 
+    /**
+     * @return returns the spatial the control is added to, or null if the control is not attached to a spatial yet.
+     */
+    public Spatial getSpatial(){
+        return this.spatial;
+    }
+
     public void setEnabled(boolean enabled) {
         this.enabled = enabled;
         if (space != null) {

jme3-bullet/src/common/java/com/jme3/bullet/control/GhostControl.java

@@ -206,6 +206,13 @@ public class GhostControl extends PhysicsGhostObject implements PhysicsControl,
         setPhysicsRotation(getSpatialRotation());
     }
 
+    /**
+     * @return returns the spatial the control is added to, or null if the control is not attached to a spatial yet.
+     */
+    public Spatial getSpatial(){
+        return this.spatial;
+    }
+
     /**
      * Enable or disable this control.
      * <p>

jme3-bullet/src/common/java/com/jme3/bullet/control/RigidBodyControl.java

@@ -207,6 +207,13 @@ public class RigidBodyControl extends PhysicsRigidBody implements PhysicsControl
         setPhysicsRotation(getSpatialRotation());
     }
 
+    /**
+     * @return returns the spatial the control is added to, or null if the control is not attached to a spatial yet.
+     */
+    public Spatial getSpatial(){
+        return this.spatial;
+    }
+
     /**
      * Set the collision shape based on the controlled spatial and its
      * descendents.