/// <summary>
/// The main method of the FloodFill AI.
/// </summary>
/// <param name="p"> Point to start/continue the flooding from. </param>
private void Flood(Point p, int keyIndex, int slidingIndex)
{
// If the exit has already been found or we have already visited this tile, stop the flooding.
if (exitFound || visited[p.X, p.Y, keyIndex, slidingIndex])
{
return;
}
// GuardTile is subclass of HoleTile so this will return for both.
// Can't use the same for walls because DoorTile is a subclass of WallTile.
// Can't use doors for which you don't have the key.
if (tileField.GetTile(p) is HoleTile ||
tileField.GetType(p) == TileType.Wall ||
(tileField.GetType(p) == TileType.Door && (keyIndex & keys[(tileField.GetTile(p) as DoorTile).DoorColor]) == 0))
{
return;
}
// The current tile has been visited.
visited[p.X, p.Y, keyIndex, slidingIndex] = true;
// Add the current tile to the route.
route.Push(p);
// If this is the exit, the algorithm is done.
// Make sure this is after pushing p to route, otherwise you will stand still before the exit.
if (tileField.GetType(p) == TileType.End)
{
exitFound = true;
return;
}
// Check if the current tile is a keytile,
// and whether we have already picked up a key of this color.
if (tileField.GetType(p) == TileType.Key)
{
// Add the key to the keyIndex
keyIndex |= keys[(tileField.GetTile(p) as KeyTile).KeyColor];
}
// If we're on an ice tile, we need the sliding direction to see if we can change direction.
if (tileField.GetType(p) == TileType.Ice)
{
// Retrieve the current and previous point in the route.
Point current = route.Pop();
Point previous = route.Pop();
// Calculate the direction you're moving at.
slidingDirection = current - previous;
// Return the current and previous point to the route.
route.Push(previous);
route.Push(current);
}
//If you can move onto the tile behind the ice tile, you can't change direction
if (tileField.GetType(p) == TileType.Ice &&
!(tileField.GetTile(p.X + slidingDirection.X, p.Y + slidingDirection.Y) is WallTile))
{
//Only keep going in this direction
Flood(p + slidingDirection, keyIndex, slides[GetDirectionFromPoint(slidingDirection)]);
}
// Otherwise we can move in all directions.
else
{
PlayerAction[] action = getActionsInRandomOrder();
for (int i = 0; i < 5; i++)
{
if (action[i] == PlayerAction.SPECIAL && tileField.GetType(p) == TileType.Portal)
{
Flood((tileField.GetTile(p) as PortalTile).Destination, keyIndex, 0);
}
else if (action[i].IsDirection())
{
// Obstacles are checked earlier in Flood() so we only need to check whether the new point is in the tilefield.
if (!tileField.OutOfTileField(p + action[i].ToDirection().ToPoint()))
{
Flood(p + action[i].ToDirection().ToPoint(), keyIndex, 0);
}
}
}
}
// All directions are done, return to the previous point.
// If the exit has been found, keep the route intact.
if (!exitFound && route.Count > 0)
{
route.Pop();
}
}