// Given a position, produce a 64-bit material signature key.
// If the engine supports such a key, it should equal the engine's key.
internal static ulong calc_key(Position pos, int mirror)
{
Color color;
PieceType pt;
int i;
ulong key = 0;
color = mirror == 0 ? Color.WHITE : Color.BLACK;
for (pt = PieceType.PAWN; pt <= PieceType.KING; ++pt)
{
for (i = GlobalMembersTbprobe.popcount <Max15>(pos.pieces(color, pt)); i > 0; i--)
{
key ^= Zobrist.psq[(int)Color.WHITE][(int)pt][i - 1];
}
}
color = ~color;
for (pt = PieceType.PAWN; pt <= PieceType.KING; ++pt)
{
for (i = GlobalMembersTbprobe.popcount <Max15>(pos.pieces(color, pt)); i > 0; i--)
{
key ^= Zobrist.psq[(int)Color.BLACK][(int)pt][i - 1];
}
}
return(key);
}
// Given a position with 6 or fewer pieces, produce a text string
// of the form KQPvKRP, where "KQP" represents the white pieces if
// mirror == 0 and the black pieces if mirror == 1.
//C++ TO C# CONVERTER TODO TASK: Pointer arithmetic is detected on the parameter 'str', so pointers on this parameter are left unchanged:
internal static void prt_str(Position pos, sbyte *str, int mirror)
{
Color color;
PieceType pt;
int i;
color = mirror == 0 ? Color.WHITE : Color.BLACK;
for (pt = PieceType.KING; pt >= PieceType.PAWN; --pt)
{
for (i = GlobalMembersTbprobe.popcount <Max15>(pos.pieces(color, pt)); i > 0; i--)
{
*str++ = GlobalMembersTbcore.pchr[6 - pt];
}
}
*str++ = 'v';
color = ~color;
for (pt = PieceType.KING; pt >= PieceType.PAWN; --pt)
{
for (i = GlobalMembersTbprobe.popcount <Max15>(pos.pieces(color, pt)); i > 0; i--)
{
*str++ = GlobalMembersTbcore.pchr[6 - pt];
}
}
*str++ = 0;
}