@Override
 public boolean pinch(
     Vector2 initialFirstPointer,
     Vector2 initialSecondPointer,
     Vector2 firstPointer,
     Vector2 secondPointer) {
   if (!(initialFirstPointer.equals(oldInitialFirstPointer)
       && initialSecondPointer.equals(oldInitialSecondPointer))) {
     oldInitialFirstPointer = initialFirstPointer.cpy();
     oldInitialSecondPointer = initialSecondPointer.cpy();
     oldScale = gameScreen.getCameraZoom();
   }
   Vector3 center =
       new Vector3(
           (firstPointer.x + initialSecondPointer.x) / 2,
           (firstPointer.y + initialSecondPointer.y) / 2,
           0);
   gameScreen.zoomCamera(
       center,
       oldScale * initialFirstPointer.dst(initialSecondPointer) / firstPointer.dst(secondPointer));
   return true;
 }
 @Override
 public boolean scrolled(int amount) {
   Vector3 mouse = new Vector3(Gdx.input.getX(), Gdx.input.getY(), 0);
   gameScreen.zoomCamera(mouse, gameScreen.getCameraZoom() - (amount * SCROLL_SCALE));
   return false;
 }