Orbit Camera is inverse

I have this orbit camera test class, but when I move the mouse up, the camera goes down, when I mvoe the mosue to left, the camera goes to right, and vice-versa. How can I change that, in a way that, when you move the mouse to, for example,  left, the camera goes to left?



My code:


import com.jme.app.SimpleGame;
import com.jme.bounding.BoundingBox;
import com.jme.bounding.BoundingSphere;
import com.jme.input.MouseInput;
import com.jme.input.MouseInputListener;
import com.jme.math.FastMath;
import com.jme.math.Vector3f;
import com.jme.scene.CameraNode;
import com.jme.scene.Node;
import com.jme.scene.shape.Box;
import com.jme.scene.shape.Sphere;


public class TestOrbitingCamera extends SimpleGame {
   boolean isOrbiting = false;
   float camX = 0;
   float camY = 0;
   protected int camDistance = 10;
   private Node pivotNode;
   
   @Override
   protected void simpleInitGame() {
      // remove existing SimpleGame input handler
      input.removeAllFromAttachedHandlers();
      
      Sphere center = new Sphere("center", 15, 15, 3);
      center.setModelBound(new BoundingSphere());
      center.updateModelBound();
      rootNode.attachChild(center);
      
      Sphere s1 = new Sphere("center", 15, 15, 1);
      s1.setLocalTranslation(-5, 4, 0);
      s1.setModelBound(new BoundingSphere());
      s1.updateModelBound();
      rootNode.attachChild(s1);
      
      Sphere s2 = new Sphere("center", 15, 15, 1);
      s2.setLocalTranslation(7, 5, 5);
      s2.setModelBound(new BoundingSphere());
      s2.updateModelBound();
      rootNode.attachChild(s2);
      
      // to have a reference
      Box b = new Box("floor", new Vector3f(-5, -10, -5), 10, 0.3f, 10);
      b.setModelBound(new BoundingBox());
      b.updateModelBound();
      rootNode.attachChild(b);
      
      MouseInput.get().addListener(new MouseInputListener() {
         @Override
         public void onWheel(int wheelDelta, int x, int y) {
         }
         @Override
         public void onMove(int xDelta, int yDelta, int newX, int newY) {
            if (isOrbiting) {
               float speed = 100f;
               camX += xDelta*tpf*speed;
               camY += yDelta*tpf*speed;
               
               // rotate the pivot node
               pivotNode.getLocalRotation().fromAngles(camY*FastMath.DEG_TO_RAD, camX*FastMath.DEG_TO_RAD, 0);
            }
         }
         @Override
         public void onButton(int button, boolean pressed, int x, int y) {
            if (button == 0 && pressed) {
               isOrbiting = true;
            }
            if (button == 0 && pressed == false) {
               isOrbiting = false;
            }
         }
      });
      
      // create a pivot Node which will be rotated by the mouse input
      pivotNode = new Node("pivot");
      rootNode.attachChild(pivotNode);
      
      // create a camera node which is attached to the pivot node and translated by the viewing distance
      CameraNode camNode = new CameraNode("camNode", cam);
      camNode.setLocalTranslation(0, 0, -30);
      pivotNode.attachChild(camNode);
   }
   
   public static void main(String[] args) {
      SimpleGame game = new TestOrbitingCamera();
      game.setConfigShowMode(ConfigShowMode.AlwaysShow);
      game.start();
   }
}


Help! Please!

Quickest way would be changing these lines:


camX += xDelta*tpf*speed;
camY += yDelta*tpf*speed;