double AiPlayer::alphaBeta(Board nodeBoard, int depth, double alpha, double beta, bool maximising) {
if (depth == 0 || nodeBoard.hasWinner()) {
return getStaticValue(nodeBoard)/(maxDepth_ - depth + 1);
}
else if (maximising) {
double staticValue = alpha;
int filledColumns = 0;
for (int column = 0; column < nodeBoard.getWidth(); column++) {
if (nodeBoard.isValidMove(column)) {
Board childNodeBoard(nodeBoard);
childNodeBoard.placeToken(column, false);
staticValue = std::max(staticValue, alphaBeta(childNodeBoard, depth - 1, alpha, beta, false));
alpha = std::max(alpha, staticValue);
if (beta <= alpha) break;
}
else filledColumns += 1;
}
return filledColumns == 7 ? getStaticValue(nodeBoard) / (maxDepth_ - depth + 1) : staticValue;
}
else {
double staticValue = beta;
int filledColumns = 0;
for (int column = 0; column < nodeBoard.getWidth(); column++) {
if (nodeBoard.isValidMove(column)) {
Board childNodeBoard(nodeBoard);
childNodeBoard.placeToken(column, true);
staticValue = std::min(staticValue, alphaBeta(childNodeBoard, depth - 1, alpha, beta, true));
beta = std::min(beta, staticValue);
if (beta <= alpha) break;
}
else filledColumns += 1;
}
return filledColumns == 7 ? getStaticValue(nodeBoard) / (maxDepth_ - depth + 1) : staticValue;
}
}
QVariant JClass::getStaticValue(const char* name, JSignature sig) const
{
QByteArray ba = sig.str().toLatin1();
return getStaticValue(name, ba.data());
}