/// <summary>
/// Creates a scene graph node with the specified node name.
/// </summary>
/// <param name="name">The name of this node</param>
public Node(String name)
{
this.name = name;
id = State.GetNextNodeID();
groupID = 0;
enabled = true;
parent = null;
scene = null;
userData = null;
}
/// <summary>
/// Clones this scene node without its children
/// </summary>
/// <returns>A cloned node</returns>
public virtual Node CloneNode()
{
Node node = new Node();
node.Name = this.Name + node.ID;
node.GroupID = this.GroupID;
node.Enabled = this.Enabled;
return node;
}
/// <summary>
/// Disposes this node.
/// </summary>
public virtual void Dispose()
{
parent = null;
scene = null;
}
protected void PropagateSceneGraph(Node node)
{
node.SceneGraph = node.Parent.SceneGraph;
if(node is BranchNode)
foreach (Node child in ((BranchNode)node).Children)
PropagateSceneGraph(child);
}
/// <summary>
/// Check whether this node is part of a cyclic graph
/// </summary>
/// <param name="node"></param>
protected void CheckForLoops(Node node)
{
Node predecessor = this;
while (predecessor.Parent != null)
{
predecessor = predecessor.Parent;
if (predecessor == node)
throw new GoblinException("Not allowed to create cyclic scene graph");
}
}
/// <summary>
/// Removes a child from this node.
/// </summary>
/// <param name="node">The child to be removed</param>
public virtual void RemoveChild(Node node)
{
if (!children.Contains(node))
return;
node.Parent = null;
node.SceneGraph = null;
if(node is BranchNode)
foreach (Node child in ((BranchNode)node).Children)
PropagateSceneGraph(child);
// at this time, still don't remove the node from children to guarantee thread-safe operation
// will be actually removed during processing the scene graph in Scene class
NodeChangeInfo info = new NodeChangeInfo();
info.Node = node;
info.Type = ChangeType.Remove;
changeList.Add(info);
}
/// <summary>
/// Adds a child to this node.
/// </summary>
/// <param name="node">The child node to be added</param>
public virtual void AddChild(Node node)
{
if (node.Parent != null)
throw new GoblinException(node.Name + " already has a parent");
if (children.Contains(node))
throw new GoblinException("This child is already added to this node");
if (node == this)
throw new GoblinException("You cannot add a node to itself");
if (node.Parent == this)
throw new GoblinException(Name + " already has " + node.Name + " as child");
CheckForLoops(node);
if (scene != null && scene.IsStarted)
{
// at this time, still don't add the node to children to guarantee thread-safe operation
// will be actually added during processing the scene graph in Scene class
NodeChangeInfo info = new NodeChangeInfo();
info.Node = node;
info.Type = ChangeType.Add;
changeList.Add(info);
}
// if the scene hasn't started processing the tree yet, then it's safe to add now
else
children.Add(node);
node.Parent = this;
PropagateSceneGraph(node);
}
public override void AddChild(Node node)
{
base.AddChild(node);
if (SwitchID < 0)
SwitchID = 0;
}