// kbnk_mate_table() tries to drive toward corners A1 or H8,
// if we have a bishop that cannot reach the above squares we
// mirror the kings so to drive enemy toward corners A8 or H1.
- if (opposite_color_squares(bishopSquare, SQ_A1))
+ if (opposite_colors(bishopSquare, SQ_A1))
{
winnerKSq = mirror(winnerKSq);
loserKSq = mirror(loserKSq);
Square queeningSq = relative_square(strongerSide, make_square(pawnFile, RANK_8));
Square kingSq = pos.king_square(weakerSide);
- if ( opposite_color_squares(queeningSq, bishopSq)
+ if ( opposite_colors(queeningSq, bishopSq)
&& abs(file_of(kingSq) - pawnFile) <= 1)
{
// The bishop has the wrong color, and the defending king is on the
// Case 1: Defending king blocks the pawn, and cannot be driven away
if ( file_of(weakerKingSq) == file_of(pawnSq)
&& relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq)
- && ( opposite_color_squares(weakerKingSq, strongerBishopSq)
+ && ( opposite_colors(weakerKingSq, strongerBishopSq)
|| relative_rank(strongerSide, weakerKingSq) <= RANK_6))
return SCALE_FACTOR_ZERO;
// Case 2: Opposite colored bishops
- if (opposite_color_squares(strongerBishopSq, weakerBishopSq))
+ if (opposite_colors(strongerBishopSq, weakerBishopSq))
{
// We assume that the position is drawn in the following three situations:
//
Square wbsq = pos.piece_list(strongerSide, BISHOP)[0];
Square bbsq = pos.piece_list(weakerSide, BISHOP)[0];
- if (!opposite_color_squares(wbsq, bbsq))
+ if (!opposite_colors(wbsq, bbsq))
return SCALE_FACTOR_NONE;
Square ksq = pos.king_square(weakerSide);
// some square in the frontmost pawn's path.
if ( file_of(ksq) == file_of(blockSq1)
&& relative_rank(strongerSide, ksq) >= relative_rank(strongerSide, blockSq1)
- && opposite_color_squares(ksq, wbsq))
+ && opposite_colors(ksq, wbsq))
return SCALE_FACTOR_ZERO;
else
return SCALE_FACTOR_NONE;
// in front of the frontmost pawn's path, and the square diagonally behind
// this square on the file of the other pawn.
if ( ksq == blockSq1
- && opposite_color_squares(ksq, wbsq)
+ && opposite_colors(ksq, wbsq)
&& ( bbsq == blockSq2
|| (pos.attacks_from<BISHOP>(blockSq2) & pos.pieces(BISHOP, weakerSide))
|| abs(r1 - r2) >= 2))
return SCALE_FACTOR_ZERO;
else if ( ksq == blockSq2
- && opposite_color_squares(ksq, wbsq)
+ && opposite_colors(ksq, wbsq)
&& ( bbsq == blockSq1
|| (pos.attacks_from<BISHOP>(blockSq1) & pos.pieces(BISHOP, weakerSide))))
return SCALE_FACTOR_ZERO;
if ( file_of(weakerKingSq) == file_of(pawnSq)
&& relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq)
- && ( opposite_color_squares(weakerKingSq, strongerBishopSq)
+ && ( opposite_colors(weakerKingSq, strongerBishopSq)
|| relative_rank(strongerSide, weakerKingSq) <= RANK_6))
return SCALE_FACTOR_ZERO;