public override bool Equals(object obj)
{
if (obj == null || GetType() != obj.GetType())
{
return(false);
}
AStarSearchNode <T> objNode = (AStarSearchNode <T>)obj;
return(node.Equals(objNode.node));
}
public T[] PerformSearch(T origin,
T destination,
AStarMapFeeder <T> feeder)
{
ClearSearch();
AddOpenNode(origin);
while (searchOpenNodes.Count > 0 && !feeder.SameNode(searchOpenNodes[0].node, destination))
{
AStarSearchNode <T> current = searchOpenNodes[0];
RemoveOpenNode(current);
AddClosedNode(current);
visitedNodes.Add(current.node);
T[] neighbours = feeder.GetNeighbours(current.node);
foreach (T neighbour in neighbours)
{
float cost = current.pathCost + feeder.GetMoveCost(current.node, neighbour);
AStarSearchNode <T> neighbourSearch = searchNodes.ContainsKey(neighbour)?
searchNodes[neighbour] :
new AStarSearchNode <T>(neighbour,
cost,
cost + feeder.GetDistanceEstimation(neighbour, destination),
current.node);
bool inOpen = openNodes.Contains(neighbour);
bool inClosed = closedNodes.Contains(neighbour);
bool smallerCost = cost < neighbourSearch.pathCost;
if (inOpen && smallerCost)
{
RemoveOpenNode(neighbourSearch);
}
else if (inClosed && smallerCost)
{
RemoveClosedNode(neighbourSearch);
}
else if (!inOpen && !inClosed)
{
AddOpenNode(neighbourSearch);
}
}
}
if (searchOpenNodes.Count > 0)
{
path = GetParentPathFrom(searchOpenNodes[0], origin, feeder);
}
return(path);
}
private void AddOpenNode(AStarSearchNode <T> searchNode)
{
if (openNodes.Contains(searchNode.node) || searchNodes.ContainsKey(searchNode.node))
{
return;
}
searchOpenNodes.Add(searchNode);
searchNodes.Add(searchNode.node, searchNode);
openNodes.Add(searchNode.node);
searchOpenNodes.Sort((AStarSearchNode <T> searchNode1,
AStarSearchNode <T> searchNode2) =>
{
return(searchNode1.queueRank.CompareTo(searchNode2.queueRank));
});
}
private T[] GetParentPathFrom(AStarSearchNode <T> searchNode, T origin, AStarMapFeeder <T> feeder)
{
List <T> parentList = new List <T>();
do
{
parentList.Add(searchNode.node);
if (searchNodes.ContainsKey(searchNode.parent))
{
searchNode = searchNodes[searchNode.parent];
}
}while(!feeder.SameNode(searchNode.node, origin) &&
!feeder.SameNode(searchNode.node, searchNode.parent));
if (feeder.SameNode(searchNode.node, origin))
{
parentList.Add(searchNode.node);
}
parentList.Reverse();
return(parentList.ToArray());
}
private void RemoveClosedNode(AStarSearchNode <T> searchNode)
{
searchClosedNodes.Remove(searchNode);
closedNodes.Remove(searchNode.node);
}
private void AddClosedNode(AStarSearchNode <T> searchNode)
{
searchClosedNodes.Add(searchNode);
closedNodes.Add(searchNode.node);
}
private void RemoveOpenNode(AStarSearchNode <T> searchNode)
{
searchOpenNodes.Remove(searchNode);
openNodes.Remove(searchNode.node);
}
private void AddOpenNode(T node)
{
AStarSearchNode <T> searchNode = new AStarSearchNode <T>(node);
AddOpenNode(searchNode);
}