protected GraphNodeMetaData <T> GetMeta(T node, bool onlyExisting = false)
{
if (MetaDict.TryGetValue(node, out var meta))
{
return(meta);
}
if (onlyExisting)
{
throw new InvalidOperationException($"MetaDict data not found for {node}. The Equals or GetHashCode function on {typeof(T).Name} is likely invalid");
}
var fromCost = Traverser.RealCost(CurrentMetaData.Node, node);
meta = new GraphNodeMetaData <T>(node, _nextGraphNodeId++)
{
ToCost = Traverser.EstimatedCost(node, Destination),
FromCost = CurrentMetaData.FromCost + fromCost,
Parent = CurrentMetaData,
PathLength = CurrentMetaData.PathLength + 1
};
MetaDict.Add(node, meta);
// If the fromCost has a negative value, it is not actually traversable so
// close the node to prevent it from being searched further.
// TODO determine if this should actually be the case
if (fromCost < 0)
{
meta.Status = NodeStatus.Closed;
}
return(meta);
}
protected virtual void ProcessNeighbor(GraphNodeMetaData <T> neighborMetaData)
{
if (neighborMetaData.Status != NodeStatus.New)
{
return;
}
neighborMetaData.Status = NodeStatus.Open;
var didAdd = OpenNodes.Add(ref neighborMetaData.Handle, neighborMetaData);
Debug.Assert(didAdd, "Failed to add neighborNode to open nodes list. The comparer is probably invalid.");
}
private void SetCurrentNode()
{
// get the best node, remove from open nodes, set to closed
CurrentMetaData = OpenNodes.DeleteMin();
ClosedCount++;
CurrentMetaData.Status = NodeStatus.Closed;
// check if this node is closest to the target
if (CurrentMetaData.ToCost < _closest.ToCost)
{
_closest = CurrentMetaData;
}
}
protected SolverBase(T origin, T destination, INodeTraverser <T> traverser = null)
{
Origin = origin ?? throw new ArgumentNullException(nameof(origin));
Destination = destination ?? throw new ArgumentNullException(nameof(destination));
Traverser = traverser ??
GetDefaultTraverser(origin) ??
throw new ArgumentException("Either Traverser needs to be passed, or T must be an ITraversableNode", nameof(traverser));
// create the origin node metadata manually as the "GetMeta" method
// needs to use the CurrentMetaData
CurrentMetaData = new GraphNodeMetaData <T>(origin, 0)
{
ToCost = Traverser.EstimatedCost(origin, Destination),
PathLength = 0,
};
OpenNodes = new C5.IntervalHeap <GraphNodeMetaData <T> >(this)
{
CurrentMetaData
};
_closest = CurrentMetaData;
// set to 1 because the origin is node 0
_nextGraphNodeId = 1;
}
public bool Equals(GraphNodeMetaData <T> other) => other != null && Node.Equals(other.Node);
public abstract int Compare(GraphNodeMetaData <T> x, GraphNodeMetaData <T> y);