LightsMap::iterator itr = _lights.begin();

while (itr != _lights.end())
{
    osg::Group* node = itr->second->asGroup();
    if (!node) continue;

    bool boundToNode = false;
    if (node->getUserValue("BoundToNode", boundToNode) && boundToNode)
    {
        if (node->getNumChildren())
        {
            osg::Matrixd mx;
            osg::Node* child = node->getChild(0);
            if (child->getUserValue("ViewMatrix", mx))
            {
                ++itr;
                continue;
            }
        }
    }

    osg::NodePath np;
    np.insert(np.begin(), node->getChild(0));
    np.insert(np.begin(), node);

    osg::ref_ptr<osg::Group> parent = node->getNumParents() ? node->getParent(0) : 0;
    while (parent)
    {
        np.insert(np.begin(), parent);
        parent = parent->getNumParents() ? parent->getParent(0) : 0;
    }

    osg::Matrixd mx = osg::computeLocalToWorld(np);

    if (node->getNumChildren())
    {
        osg::Node* child = node->getChild(0);
        osg::Matrixd plus90 = OpenIG::Base::Math::instance()->toMatrix(0.0, 0.0, 0.0, 0.0, 90.0, 0.0) * mx;

#if 0
        mx.makeLookAt(mx.getTrans(), osg::Vec3(0, 0, 0), osg::Vec3(0, 0, 1));
        child->setUserValue("ViewMatrix", mx);
#else
        child->setUserValue("ViewMatrix", osg::Matrixd::inverse(plus90));
        child->setUserValue("WorldMatrix", mx);
#endif
    }

    ++itr;
}