public MovePly branchPromotion()
{
var promoPly = new MovePly(c, movedIndex, square, move);
promoPly.setCaptureIndex(capturedIndex);
promoPly.setPromotion();
return promoPly;
}
// Returns a list of all possible plies
public List<Ply> children(Bits[] position, int c)
{
var plies = new List<Ply> ();
// Calculate all squares not occupied by pieces of colour c
Bits notCPieces = (Bits)((~colourPieces (position, c)) & ((1 << files*columns) - 1));
// Calculate all squares occupied by pieces of colour (c ^ 1)
Bits enemyPieces = colourPieces (position, (c ^ 1));
// Loop through each piece type
for (int p = 0; p < l; ++p) {
// Extract each individual piece
foreach (Bits square in B.allOnes(position[p + c * l]))
{
// Check its moves
var singleMoves = moves (square, p, c, notCPieces);
// For each move create a ply
foreach (Bits move in singleMoves) {
var ply = new MovePly (c, p, square, move);
if (B.Overlaps(move, enemyPieces))
ply.setCaptureIndex (capture (position, move, c));
// Add ply without promotion
plies.Add (ply);
// Check for promotion and branch if it is possible
if (p < pieces.Length && pieces [p].ptype != Type.None)
if (B.Overlaps (promoMask [c], square) || B.Overlaps (promoMask [c], move)) {
plies.Add (ply.branchPromotion ());
}
}
}
}
// Get the players hand information
Bits hand = position [2 * l + c];
// If it is not empty calculate empty squares
if (hand != 0) {
Bits all = (Bits)(notCPieces ^ (enemyPieces));
// Loop through all piece types
foreach (var pieceMask in handMask) {
// Check if the player has this piece
if (B.Overlaps(hand, pieceMask.Value))
// Calculate all positions where it can be dropped
foreach (Bits square in B.allOnes(all)) {
// Add a drop ply for each possible drop
plies.Add (new DropPly (c, pieceMask.Key, square));
}
}
}
// Return all possible plies
return plies;
}
