public float distanceToNearPlane(Vector3f pos) {
        return worldPlane[NEAR_PLANE].pseudoDistance(pos);
    }
Returns the pseudo distance from the given position to the near
plane of the camera. This is used for render queue sorting.
@param pos The position to compute a distance to.
@return Distance from the near plane to the point.
jme3-core/src/main/java/com/jme3/renderer/Camera.java