worldBound = (BoundingVolume) child.getWorldBound() .clone(worldBound);
worldBound = child.getWorldBound().clone(worldBound);
    public void updateWorldBound() {        if ((lockedMode & SceneElement.LOCKED_BOUNDS) != 0) return;        if (children == null) {            return;        }         boolean foundFirstBound = false;        for (int i = 0, cSize = children.size(); i < cSize; i++) {            Spatial child =  children.get(i);            if (child != null) {                if (foundFirstBound) {                    // merge current world bound with child world bound                    worldBound.mergeLocal(child.getWorldBound());                } else {                    // set world bound to first non-null child world bound                    if (child.getWorldBound() != null) {                        worldBound = (BoundingVolume) child.getWorldBound()                                .clone(worldBound);                        foundFirstBound = true;                    }                }            }        }    }