/// <summary>
/// Recursively solves the puzzle using a brute-force backtracking algorithm.
/// </summary>
/// <param name="row"></param>
/// <param name="col"></param>
/// <returns></returns>
private async Task <bool> PerformSolve(int row, int col)
{
if (IsPuzzleSolved())
{
// Puzzle has been solved - return
return(true);
}
else if (Puzzle.Tiles[row, col].Value != 0)
{
// Tile is already solved - proceed to next
return(await NextSolve(row, col));
}
else
{
// Attempt each possible value 1-9 in this cell
for (var value = 1; value <= Puzzle.Height; value++)
{
// This is a valid placement of this value, causing no issues with constraints
if (ValidateValue(row, col, value))
{
// Set the tile value and attempt to recursively solve the rest of the board.
Puzzle.Tiles[row, col].Value = value;
TileUpdated?.Invoke(this, new TileUpdatedEventArgs {
Tile = Puzzle.Tiles[row, col]
});
// Intentional delay inbetween solving each tile
if (WaitFor > 0)
{
await Task.Delay(WaitFor);
}
if (await NextSolve(row, col))
{
return(true);
}
// If any position comes back with an invalid move, rollback this value and try the next
Puzzle.Tiles[row, col].Value = 0;
TileUpdated?.Invoke(this, new TileUpdatedEventArgs {
Tile = Puzzle.Tiles[row, col]
});
}
}
}
return(false);
}
public void AddTileMap(Image image)
{
Bitmap bitmap = new Bitmap(image);
//int currentImageID = TileSetImages.Count + StartIndex;
//TileSetImages.Add(bitmap);
for (int i = 0; i <= image.Height - TileSize; i += TileSize)
{
for (int j = 0; j <= image.Width - TileSize; j += TileSize)
{
Rectangle target = new Rectangle(j, i, TileSize, TileSize);
Bitmap tmp = bitmap.Clone(target, System.Drawing.Imaging.PixelFormat.DontCare);
Tiles.Add(tmp);
TilesData.Add(new TileData(this.StartIndex + Tiles.Count - 1, i / TileSize, j / TileSize));
}
}
bitmap.Dispose();
if (TileUpdated != null)
{
TileUpdated.Invoke(this, new EventArgs());
}
}
protected void OnTileUpdated(Tile tile)
{
TileUpdated.Raise(this, new TileUpdatedEventArgs(tile));
}