public static Stack <GridCell> GetPath(GridCell start, GridCell end)
{
GetGridCells();
//Instantiate lists
Stack <GridCell> path = new Stack <GridCell> ();
HashSet <GridCell> openList = new HashSet <GridCell> ();
HashSet <GridCell> closedList = new HashSet <GridCell> ();
GridCell currentGridCell = start;
openList.Add(currentGridCell);
while (openList.Count > 0)
{
//Check x axis
for (int x = -1; x <= 1; x++)
{
GridPos pos = new GridPos(currentGridCell.gridPos.x - x, currentGridCell.gridPos.y);
if (cells.ContainsKey(pos))
{
GridCell nextGridCell = cells [pos];
//Check content
if (nextGridCell.CanMoveThrough())
{
//Check if already in open list, if so, check if a better parent.
if (openList.Contains(nextGridCell))
{
if (currentGridCell.g + 1 < nextGridCell.g)
{
nextGridCell.CalcValues(currentGridCell, end);
}
}
//Check if not in closed list, if so, add to open list.
else if (!closedList.Contains(nextGridCell))
{
openList.Add(nextGridCell);
nextGridCell.CalcValues(currentGridCell, end);
}
}
}
}
//Check y axis
for (int y = -1; y <= 1; y++)
{
GridPos pos = new GridPos(currentGridCell.gridPos.x, currentGridCell.gridPos.y - y);
if (cells.ContainsKey(pos))
{
GridCell nextGridCell = cells [pos];
//Check content
if (nextGridCell.CanMoveThrough())
{
//Check if already in open list, if so, check if a better parent.
if (openList.Contains(nextGridCell))
{
if (currentGridCell.g + 1 < nextGridCell.g)
{
nextGridCell.CalcValues(currentGridCell, end);
}
}
//Check if not in closed list, if so, add to open list.
else if (!closedList.Contains(nextGridCell))
{
openList.Add(nextGridCell);
nextGridCell.CalcValues(currentGridCell, end);
}
}
}
}
//End for loops.
//Remove current tile from open list and add it to the closed list.
openList.Remove(currentGridCell);
closedList.Add(currentGridCell);
//Sort the open list by lowest F score.
if (openList.Count > 0)
{
currentGridCell = openList.OrderBy(c => c.f).First();
}
//If goal is found, add it and it's parents to the Path. Then break.
if (currentGridCell == end)
{
while (currentGridCell.gridPos != start.gridPos)
{
path.Push(currentGridCell);
currentGridCell = currentGridCell.parent;
}
break;
}
}
//End while loop
return(path);
}