[osg-users] Could I update the structure of scene in a node visitor?

[zhuliangxiong]

Hi there,

i wrote a class inherit from NodeVistor to remove all the scribe node from the 
scene. However, after the execution leave my apply function, the system 
crashed. I think that's because i changed the structure of the scene since i 
removed nodes from scene when visiting, and that may make some iterator 
unusable.

so, is it available to change the structure of scene in a NodeVistor ?  If yes, 
is there anything to take care?
following are code episode:
1. constructor :
ClearSelectionNodeVisitor::ClearSelectionNodeVisitor(void)
:NodeVisitor(NodeVisitor::UPDATE_VISITOR,NodeVisitor::TRAVERSE_ALL_CHILDREN)
{}

2. apply function
void ClearSelectionNodeVisitor::apply(Node& node){
    Node::ParentList parentList=node.getParents();
    //iterate all the parent to find whether it has a Scribe as parent node.
    for(Node::ParentList::iterator it=parentList.begin();
        it!=parentList.end();++it){
        Group* parent=*it;
        Scribe* scribe=dynamic_cast<Scribe*>(parent);
        if(parent&&scribe)
        {            
            Node::ParentList ancestorList=parent->getParents();
           //replace the scribe in its parent with the current node who is the 
child of this scribe.
            for(Node::ParentList::iterator ast=ancestorList.begin();
                ast!=ancestorList.end();++ast){
                    (*ast)->replaceChild(scribe,&node);
            } 
           // node has been moved, so the parentList maybe changed . 
re-identify the begin.
            it=parentList.begin ();
        }
    }
    traverse(node);
}

any comment is appreciative.

Regards,
Abe. Zhu

_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org