// MiniMax
private int AlphaBetaPruning(Vector2Int cell, int depth, int alpha = -int.MaxValue, int beta = int.MaxValue, bool maximazingPlayer = false)
{
if (depth == 0 || (boardData.IsCellOccupied(FigureType.King, cell) &&
boardData.IsCellOccupied(maximazingPlayer ? FigureType.Black : FigureType.White, cell)))
{
return(Evaluate(cell));
}
if (maximazingPlayer)
{
int maxEvaluation = -int.MaxValue;
Vector2Int[] possiblePositions = boardData.GetPossibleMoves(figureType, cell, maximazingPlayer);
foreach (Vector2Int position in possiblePositions)
{
int evaluation = AlphaBetaPruning(position, depth - 1, alpha, beta, false);
maxEvaluation = Mathf.Max(maxEvaluation, evaluation);
alpha = Mathf.Max(alpha, evaluation);
if (evaluation > alpha)
{
alpha = evaluation;
maxEvaluation = evaluation;
tempBestMove = position;
}
if (beta <= alpha)
{
break;
}
}
return(maxEvaluation);
}
else
{
int minEvaluation = int.MaxValue;
Vector2Int[] possiblePositions = boardData.GetPossibleMoves(figureType, cell, maximazingPlayer);
foreach (Vector2Int position in possiblePositions)
{
int evaluation = AlphaBetaPruning(position, depth - 1, alpha, beta, true);
if (evaluation < beta)
{
beta = evaluation;
minEvaluation = evaluation;
tempBestMove = position;
}
if (beta <= alpha)
{
break;
}
}
return(minEvaluation);
}
}
private int Negamax(Vector2Int cell, int depth, bool white)
{
if (depth == 0 || (boardData.IsCellOccupied(FigureType.King, cell) &&
boardData.IsCellOccupied(white ? FigureType.Black : FigureType.White, cell)))
{
return(Evaluate(boardData.GetFigureType(cell), cell));
}
int evaluation = int.MinValue;
Vector2Int[] whitePieces = boardData.GetAllChessPiecesByColor(white);
foreach (Vector2Int piece in whitePieces)
{
FigureType type = boardData.GetFigureType(piece);
Vector2Int[] possibleMoves = boardData.GetPossibleMoves(type, piece, white);
foreach (Vector2Int position in possibleMoves)
{
int i = -Negamax(position, depth - 1, !white);
if (i > evaluation)
{
evaluation = i;
trueMove.from = piece;
trueMove.to = position;
}
}
}
return(evaluation);
}
public void HighlightPossibleMoves(Vector2Int pos)
{
UnhighlightPreviousMoves();
FigureType figureType = boardData.GetFigureType(pos.x, pos.y);
savedPossibleMoves = boardData.GetPossibleMoves(figureType, pos.x, pos.y);
for (int i = 0; i < savedPossibleMoves.Length; i++)
{
HighlightCell(savedPossibleMoves[i]);
}
}
public void HighlightPossibleMoves(Vector2Int pos)
{
UnhighlightPreviousMoves();
FigureType figureType = boardData.GetFigureType(pos);
savedPossibleMoves = boardData.GetPossibleMoves(figureType, pos);
int size = savedPossibleMoves.Length;
for (int i = 0; i < size; i++)
{
highlightCell[i].transform.position = new Vector3(savedPossibleMoves[i].x, savedPossibleMoves[i].y);
highlightCell[i].SetActive(true);
}
}
