/// <summary>
/// check whether a tile should be highlighted as attackable
/// </summary>
/// <param name="tileCoords"></param>
/// <returns>true if it tile was highlighted, false if it was blocked</returns>
private bool CheckAndHighlightAttackableTile(Coords tileCoords)
{
if (!Grid.InMap(tileCoords))
{
return(false);
}
bool isFree = _grid.IsFree(tileCoords);
//highlight if tile is free or if isn't free but has enemy
if (isFree || _grid.IsEnemy(tileCoords))
{
GroundController tile = _mapGenerator.GetTile(tileCoords);
tile.SetHighlight(GroundController.HighlightType.Attackable);
//add to highlighted tiles list
_highlightedTiles.Add(tile);
return(true);
}
return(false);
}
/// <summary>
/// Solve the given Grid using the BFS method
/// </summary>
/// <param name="grid">grid object to solve</param>
/// <param name="start">starting coordinates</param>
/// <param name="destination">destination coordinates</param>
/// <param name="range">the number of spaces allowed to move</param>
public void Solve(Grid grid, Coords start, Coords destination, int range)
{
_terrain = grid;
_start = start;
_destination = destination;
const int xLength = Grid.GridWidth;
const int yLength = Grid.GridHeight;
//check if destination NOT reachable
if (!Grid.InMap(_destination) && !_terrain.IsFree(_destination))
{
//if destination isn't free, there's no solution
_foundSolution = false;
return;
}
// track locations we've been to using our terrain "memory"
Cell defaultCell = new Cell(Color.White);
_memory = new Cell[xLength, yLength];
//Fill the memory with default cells
for (int x = 0; x < xLength; x++)
{
for (int y = 0; y < yLength; y++)
{
_memory[x, y] = defaultCell.Copy();
}
}
Queue <Coords> toCheck = new Queue <Coords>(); //holds the spaces to check. Spaces in queue will be grey
// track the current search location, starting at the start of queue
Coords current = _start;
while (!current.Equals(_destination)) //search have not reached goal yet
{
// record that we've been here
_memory[current.X, current.Y].SetColor(Color.Black);
// find the next direction. Check Up, down, left, right for white space
foreach (Direction directionToCheck in DirectionMethods.GetClockwise()) //loop over each direction in clockwise order
{
Coords next = current.Get(directionToCheck); //next is the location of the next square to check
if (Grid.InMap(next) && _terrain.IsFree(next) && _memory[next.X, next.Y].GetColor() == Color.White) //part of terrain and free space and not visited
{
//next space is white. record it as grey and add to queue,
//then go back to current and continue looking at other directions
//set from direction of next, to backtrack from goal
_memory[next.X, next.Y].SetFrom(DirectionMethods.Opposite(directionToCheck));
//set color to grey(seen)
_memory[next.X, next.Y].SetColor(Color.Grey);
//set the distance to distance of current + 1
_memory[next.X, next.Y].SetDistance(_memory[current.X, current.Y].GetDistance() + 1);
//check if next is within range
if (_memory[next.X, next.Y].GetDistance() <= range)
{
//add next location to queue
toCheck.Enqueue(next);
}
}
}
//if queue is empty, BFS has searched every path and found no solution
if (toCheck.Count == 0)
{
_foundSolution = false;
return;
}
//move to next spot in queue
current = toCheck.Dequeue();
}
// we reached the goal and have a solution.
_solutionLength = _memory[current.X, current.Y].GetDistance();
_foundSolution = true;
// Get the solution in reverse and set the To of each location
current = _destination; // start at the goal
Coords previous = current; //last current
current = current.Get(_memory[current.X, current.Y].GetFrom()); //move to where we came here from
while (!current.Equals(_start)) //loop until we reach the goal
//set from direction of new current
{
Direction from = DirectionMethods.Opposite(_memory[previous.X, previous.Y].GetFrom());
_memory[current.X, current.Y].SetTo(from); //set current To as opposite of previous From
previous = current;
// step to where we came to current from
current = current.Get(_memory[current.X, current.Y].GetFrom());
}
//set to one last time for the starting spot
Direction fromLast = DirectionMethods.Opposite(_memory[previous.X, previous.Y].GetFrom());
_memory[current.X, current.Y].SetTo(fromLast); //set to as opposite of previous from
}
