function SceneGraphIterator(){
}

SceneGraphIterator.prototype.set = function(list){
    list = cur = list
}


SceneGraphIterator.prototype.hasNext = function(){
    return (cur.next) ? 1 : 0
}



SceneGraphIterator.prototype.hasNext = function(id){
    for(p in cur.next){
        if(p.sgid == id){
            return 1
	}
    }

    return 0
}


SceneGraphIterator.prototype.hasNextGroup = function(id){
    for(p in cur.next){
	if(p.gid == id){
	    return 1
	}
    }

    return 0
}



SceneGraphIterator.prototype.next = function(){
    cur = cur.next
}



SceneGraphIterator.prototype.next = function(id){
    for(p in cur.next){
        if(p.sgid == id){
	    break
	}
    }

    cur = p
}


SceneGraphIterator.prototype.nextGroup = function(id){
    for(p in cur.next){
        if(p.gid == id){
	    break
	}
    }

    cur = p
}


SceneGraphIterator.prototype.remove = function(){
    cur.remove()
}


SceneGraphIterator.prototype.get = function(){
    return cur 
}