public static PathRoute generatePath(List <Map.MapNode> closedList, Map.MapNode[,] grid, Map.MapNode Start, PathRoute Path)
{
int index = closedList.Count - 1; //need to work backwards to try and get to the start node
int PathIndex = 0;
Map.MapNode a = closedList[index];
Map.MapNode temp = a;
Path.PathList[0] = Map.ConvertGridNodeToVector(a);
++PathIndex;
while (temp.id != Start.id)
{
Path.PathList[PathIndex] = (Map.ConvertGridNodeToVector(a.parent[0]));
temp = a.parent[0];
a = temp;
++PathIndex;
}
Path.PathSize = PathIndex;
Path.Index = 0;
Array.Reverse(Path.PathList, 0, PathIndex);
return(Path);
}
public static PathRoute Search(Map.MapNode[,] MapNode, Vector3 Position, Vector3 objPosition, PathRoute Path, List <Map.MapNode> openList, List <Map.MapNode> closedList)
{
Map.MapNode start = Map.ConvertPositionToGrid(MapNode, Position);
Map.MapNode obj = Map.ConvertPositionToGrid(MapNode, objPosition);
return(aStarSearch(start, obj, openList, closedList, MapNode, Path));
}
private static PathRoute aStarSearch(Map.MapNode start, Map.MapNode obj, List <Map.MapNode> openList, List <Map.MapNode> closedList, Map.MapNode[,] grid, PathRoute path)
{
Reset(grid, openList, closedList);
Map.MapNode currentNode = start; // will be changed to whichever has the lowerest cost
int x = currentNode.posX;
int y = currentNode.posY;
currentNode.fcost = Map.HCost(obj, currentNode); // calc f cost
currentNode.cameFrom[0] = currentNode;
openList.Add(currentNode);
while (openList.Count != 0)
{
if (currentNode.id == obj.id)
{
closedList.Add(currentNode);
path = generatePath(closedList, grid, start, path);
return(path);
}
else
{
for (int i = 0; i < currentNode.neighbours.Count; i++) //loop all neighbours
{
x = currentNode.neighbours[i].posX;
y = currentNode.neighbours[i].posY;
var temp = currentNode.neighbours[i];
temp.gcost = Map.GCost(currentNode, currentNode.neighbours[i]);
temp.hcost = Map.HCost(obj, currentNode.neighbours[i]);
temp.cameFrom[0] = currentNode;
temp.fcost = temp.gcost + temp.hcost;
currentNode.neighbours[i] = temp;
for (int j = 0; j < openList.Count; j++)
{
if (openList[j].id == currentNode.neighbours[i].id) //if it's already on the open list then
{
grid[x, y].state = Map.status.onOpenList;
if (temp.fcost >= openList[j].fcost) //we already have a cheaper node
{
break;
}
if (temp.fcost < openList[j].fcost) //if this happens our heuristic is broken
{
openList[j].parent[0] = currentNode;
}
}
}
if (grid[x, y].state != Map.status.onOpenList) //if not on the openList we check if it's already on the closed list if it isn't add it to the openlist
{
for (int k = 0; k < closedList.Count; k++)
{
if (closedList[k].id == currentNode.neighbours[i].id) //if already on the closed list, check if neighbour is cheaper if it is set parent
{
grid[x, y].state = Map.status.searched;
if (temp.fcost >= closedList[k].fcost)
{
break;
}
if (temp.fcost < closedList[k].fcost)
{
closedList[k].parent[0] = currentNode;
}
}
}
if (grid[x, y].state != Map.status.searched)
{
currentNode.neighbours[i].parent[0] = currentNode;
grid[x, y].state = Map.status.onOpenList;
openList.Add(currentNode.neighbours[i]);
}
}
}
x = currentNode.posX;
y = currentNode.posY;
grid[x, y].state = Map.status.searched;
openList.Remove(currentNode);
closedList.Add(currentNode);
openList.Sort(delegate(Map.MapNode a, Map.MapNode b) { return(a.fcost.CompareTo(b.fcost)); }); //sorting function so first one on openList is cheapest
currentNode = openList[0];
}
}
return(path);
}
