protected void updateWorldTransforms() {
        if (parent == null) {
            worldTransform.set(localTransform);
            refreshFlags &= ~RF_TRANSFORM;
        } else {
            // check if transform for parent is updated
            assert ((parent.refreshFlags & RF_TRANSFORM) == 0) : "Illegal rf transform update. Problem spatial name: " + getName();
            worldTransform.set(localTransform);
            worldTransform.combineWithParent(parent.worldTransform);
            refreshFlags &= ~RF_TRANSFORM;
        }
    }
Should only be called from updateGeometricState().
In most cases should not be subclassed.
jme3-core/src/main/java/com/jme3/scene/Spatial.java