private TreeNode GetOrCreateWorldNode(DiscreteDynamicsWorld world)
{
TreeNode worldNode;
if (worldTree.Nodes.Count == 1)
{
worldNode = worldTree.Nodes[0];
if (worldNode.Tag == world)
{
return(worldNode);
}
worldTree.Nodes.Clear();
}
worldNode = worldTree.Nodes.Add(world.GetType().Name);
worldNode.Tag = world;
worldNode.Expand();
return(worldNode);
}