public PathFinder(MapContext context)
{
_context = context;
_param = new AStarParam(context.MovementGrid, DiagonalMovement.Never);
}
public static List <Point> FindPath(AStarParam iParam)
{
object lo = new object();
//var openList = new IntervalHeap<Node>(new NodeComparer());
var openList = new IntervalHeap <Node>();
var startNode = iParam.StartNode;
var endNode = iParam.EndNode;
var grid = iParam.SearchGrid;
var diagonalMovement = iParam.DiagonalMovement;
var weight = iParam.Weight;
startNode.startToCurNodeLen = 0;
startNode.heuristicStartToEndLen = 0;
openList.Add(startNode);
startNode.isOpened = true;
while (openList.Count != 0)
{
var node = openList.DeleteMin();
node.isClosed = true;
if (node == endNode)
{
return(Node.Backtrace(endNode));
}
var neighbors = grid.GetNeighbors(node);
foreach (var neighbor in neighbors)
{
if (neighbor == endNode)
{
neighbor.parent = node;
return(Node.Backtrace(neighbor));
}
if (neighbor.isClosed || neighbor.value < 0)
{
continue;
}
var X = neighbor.x;
var Y = neighbor.y;
float ng = node.startToCurNodeLen + (float)((X - node.x == 0 || Y - node.y == 0) ? 1 : Math.Sqrt(2));
if (!neighbor.isOpened || ng < neighbor.startToCurNodeLen)
{
neighbor.startToCurNodeLen = ng;
if (neighbor.heuristicCurNodeToEndLen == null)
{
neighbor.heuristicCurNodeToEndLen = neighbor.value + Heuristic.Manhattan(Math.Abs(X - endNode.x), Math.Abs(Y - endNode.y));
}
neighbor.heuristicStartToEndLen = neighbor.startToCurNodeLen + neighbor.heuristicCurNodeToEndLen.Value;
neighbor.parent = node;
if (!neighbor.isOpened)
{
lock (lo)
{
openList.Add(neighbor);
}
neighbor.isOpened = true;
}
else
{
}
}
}
}
return(new List <Point>());
}