static void Main(string[] args)
{
int[,] map =
{
{ 0, -1, 0, 0, 0, 0 },
{ 0, -1, 0, -1, 0, 0 },
{ 0, -1, 0, -1, 0, 0 },
{ 0, -1, 0, -1, 0, 0 },
{ 0, 0, 0, -1, 0, 0 },
{ 0, 0, 0, -1, 0, 0 }
};
AstarHelper astar = new AstarHelper(map, 0.1f);
var route = astar.Search(1, 1, 4, 4);
if (route != null)
{
while (route.Count() > 0)
{
int[] pos = route.Dequeue();
Console.WriteLine("{0}, {1}", pos[0], pos[1]);
}
}
}
private static void AddNeighbor(Dictionary<TileStatus, AstarHelper> OpenNodes, TileStatus lowest, TileStatus direction, TileStatus goal)
{
if(OpenNodes.ContainsKey(direction))
{
AstarHelper helper = OpenNodes[direction];
helper.actual = OpenNodes[lowest].actual + GlobalConstants.A_STAR_MOVE_COST;
helper.prev = lowest;
OpenNodes[direction] = helper;
}
else
{
AstarHelper helper = new AstarHelper();
helper.actual = OpenNodes[lowest].actual + GlobalConstants.A_STAR_MOVE_COST;
helper.heuristic = ManhattanDistance(direction.Position, goal.Position);
helper.prev = lowest;
OpenNodes[direction] = helper;
}
}
/// <summary>
/// Gets the path between two tile coordinates
/// </summary>
/// <returns>
/// The path in tiles
/// </returns>
/// <param name='start'>
/// Starting tile coordinate
/// </param>
/// <param name='end'>
/// Ending tile coordinate
/// </param>
/// <param name='type'>
/// Type of ground to consider for pathing
/// </param>
public static List<TileStatus> GetPath(Vector2 start, Vector2 end, TileStatus.GroundType type)
{
List<TileStatus> retn = new List<TileStatus>();
TileStatus endNode = GetTileAt(end.x, end.y);
TileStatus startNode = GetTileAt(start.x, start.y);
Dictionary<TileStatus, AstarHelper> OpenNodes = new Dictionary<TileStatus, AstarHelper>();
Dictionary<TileStatus, AstarHelper> ClosedNodes = new Dictionary<TileStatus, AstarHelper>();
OpenNodes[startNode] = new AstarHelper();
while(OpenNodes.Count > 0 && !OpenNodes.ContainsKey(endNode))
{
//Get the lowest cost Open Node
int min = int.MaxValue;
TileStatus lowest = null;
foreach(TileStatus status in OpenNodes.Keys)
{
if(OpenNodes[status].combined < min)
{
min = OpenNodes[status].combined;
lowest = status;
}
}
//Compute the costs of the neighbors
TileStatus up = GetTileAt(lowest.Position.x, lowest.Position.y + 1);
TileStatus down = GetTileAt(lowest.Position.x, lowest.Position.y - 1);
TileStatus left = GetTileAt(lowest.Position.x - 1, lowest.Position.y);
TileStatus right = GetTileAt(lowest.Position.x + 1, lowest.Position.y);
#region Up
if(up != null && (up.groundType & type) != 0 && !ClosedNodes.ContainsKey(up))
{
AddNeighbor(OpenNodes, lowest, up, endNode);
}
#endregion
#region down
if(down != null && (down.groundType & type) != 0 && !ClosedNodes.ContainsKey(down))
{
AddNeighbor(OpenNodes, lowest, down, endNode);
}
#endregion
#region left
if(left != null && (left.groundType & type) != 0 && !ClosedNodes.ContainsKey(left))
{
AddNeighbor(OpenNodes, lowest, left, endNode);
}
#endregion
#region right
if(right != null && (right.groundType & type) != 0 && !ClosedNodes.ContainsKey(right))
{
AddNeighbor(OpenNodes, lowest, right, endNode);
}
#endregion
ClosedNodes[lowest] = OpenNodes[lowest];
OpenNodes.Remove(lowest);
}
if(!OpenNodes.ContainsKey(endNode)) return null;
retn.Add(endNode);
TileStatus nextNode = OpenNodes[endNode].prev;
while(!retn.Contains(startNode))
{
retn.Insert(0, nextNode);
nextNode = ClosedNodes[nextNode].prev;
}
//TODO: Complete this method
return retn;
}
