public void setDirection(Vector3f direction) {
        setDirection(direction, Vector3f.UNIT_Y);
    }
Sets the direction of the spatial, using the Y axis as the up vector.
Use MotionEvent#setDirection((Vector3f direction,Vector3f upVector) if
you want a custom up vector.
This method is used by the motion path.

@param direction the desired forward direction (not null, unaffected)
jme3-core/src/main/java/com/jme3/cinematic/events/MotionEvent.java