public override void Update(GameTime gameTime)
{
if (paths == null)
{
paths = PathTree.makeEmptyRoot();
foreach (string key in ResearchTable.category.Keys)
{
paths.addChildren(PathTree.makePathTree("", key));
}
hasChanged = true;
}
if (hasChanged)
{
buildPathList();
}
Recalculate();
base.Update(gameTime);
}