public static List <Node> FindPath(GridPos start, GridPos end, GridPos[,] Grid)
{
if (Grid.GetLength(0) < start.X || Grid.GetLength(1) < start.Y || start.X < 0 || start.Y < 0)
{
return(new List <Node>());
}
Node[,] grid = new Node[Grid.GetLength(0), Grid.GetLength(1)];
if (grid[start.X, start.Y] == null)
{
grid[start.X, start.Y] = new Node(Grid[start.X, start.Y]);
}
Node Start = grid[start.X, start.Y];
var path = new MinHeap();
// push the start node into the open list
path.Push(Start);
Start.Opened = true;
// while the open list is not empty
while (path.Count > 0)
{
// pop the position of node which has the minimum `f` value.
Node node = path.Pop();
if (grid[node.X, node.Y] == null)
{
grid[node.X, node.Y] = new Node(Grid[node.X, node.Y]);
}
grid[node.X, node.Y].Closed = true;
//if reached the end position, construct the path and return it
if (node.X == end.X && node.Y == end.Y)
{
return(Backtrace(node));
}
// get neigbours of the current node
List <Node> neighbors = GetNeighbors(grid, node, Grid);
for (int i = 0, l = neighbors.Count; i < l; ++i)
{
Node neighbor = neighbors[i];
if (neighbor.Closed)
{
continue;
}
// check if the neighbor has not been inspected yet, or can be reached with
// smaller cost from the current node
if (neighbor.Opened)
{
continue;
}
if (neighbor.F == 0)
{
neighbor.F = Heuristic.Octile(Math.Abs(neighbor.X - end.X), Math.Abs(neighbor.Y - end.Y));
}
neighbor.Parent = node;
if (!neighbor.Opened)
{
path.Push(neighbor);
neighbor.Opened = true;
}
else
{
neighbor.Parent = node;
}
}
}
return(new List <Node>());
}
public static Node[,] LoadBrushFire(GridPos user, GridPos[,] mapGrid, short MaxDistance = 22)
{
Node[,] grid = new Node[mapGrid.GetLength(0), mapGrid.GetLength(1)];
if (grid[user.X, user.Y] == null)
{
grid[user.X, user.Y] = new Node(mapGrid[user.X, user.Y]);
}
Node start = grid[user.X, user.Y];
var path = new MinHeap();
// push the start node into the open list
path.Push(start);
start.Opened = true;
// while the open list is not empty
while (path.Count > 0)
{
// pop the position of node which has the minimum `f` value.
Node node = path.Pop();
if (grid[node.X, node.Y] == null)
{
grid[node.X, node.Y] = new Node(mapGrid[node.X, node.Y]);
}
grid[node.X, node.Y].Closed = true;
// get neighbors of the current node
List <Node> neighbors = GetNeighbors(grid, node, mapGrid);
for (int i = 0, l = neighbors.Count; i < l; ++i)
{
Node neighbor = neighbors[i];
if (neighbor.Closed)
{
continue;
}
// check if the neighbor has not been inspected yet, or can be reached with
// smaller cost from the current node
if (neighbor.Opened)
{
continue;
}
if (neighbor.F == 0)
{
double distance = Heuristic.Octile(Math.Abs(neighbor.X - node.X), Math.Abs(neighbor.Y - node.Y)) + node.F;
if (distance > MaxDistance)
{
neighbor.Value = 1;
continue;
}
neighbor.F = distance;
grid[neighbor.X, neighbor.Y].F = neighbor.F;
}
neighbor.Parent = node;
if (!neighbor.Opened)
{
path.Push(neighbor);
neighbor.Opened = true;
}
else
{
neighbor.Parent = node;
}
}
}
return(grid);
}
public Node(GridPos node)
{
Value = node.Value;
X = node.X;
Y = node.Y;
}
