Only test check status for one side; speeds up almost 25%.

diff --git a/Board.pm b/Board.pm
index 8cf603d0f5be052c762d3f127d7bba87dc047196..1bedd56a23d704f458384a858f69b4120cf652d4 100644 (file)
--- a/Board.pm
+++ b/Board.pm
@@ -182,8 +182,10 @@ sub parse_pretty_move {
        
        # Find all possible from-squares that could have been meant.
        my @squares = ();
        
        # Find all possible from-squares that could have been meant.
        my @squares = ();

+       my $side = 'K';

        if ($toplay eq 'B') {
                $piece = lc($piece);
        if ($toplay eq 'B') {
                $piece = lc($piece);

+               $side = 'k';

        }
        for my $row (0..7) {
                next if (defined($from_row) && $from_row != $row);
        }
        for my $row (0..7) {
                next if (defined($from_row) && $from_row != $row);


@@ -194,11 +196,7 @@ sub parse_pretty_move {
 
                        # See if doing this move would put us in check
                        # (yes, there are clients that expect us to do this).
 
                        # See if doing this move would put us in check
                        # (yes, there are clients that expect us to do this).

-                       my $check = $board->make_move($row, $col, $to_row, $to_col, $promo)->in_check();
-                       next if ($check eq 'both' ||
-                                ($toplay eq 'W' && $check eq 'white') ||
-                                ($toplay eq 'B' && $check eq 'black'));
-
+                       next if ($board->make_move($row, $col, $to_row, $to_col, $promo)->in_check($side));

                        push @squares, [ $row, $col ];
                }
        }
                        push @squares, [ $row, $col ];
                }
        }


@@ -338,64 +336,42 @@ sub can_reach {
        return 0;
 }
 
        return 0;
 }
 

-# Returns 'none', 'white', 'black' or 'both', depending on which sides are in check.
-# The latter naturally indicates an invalid position.
+# Returns whether the given side (given as k or K for black and white) is in check.

 sub in_check {
 sub in_check {

-       my $board = shift;
-       my ($black_check, $white_check) = (0, 0);
-
-       my ($wkr, $wkc, $bkr, $bkc) = _find_kings($board);
+       my ($board, $piece) = @_;
+       my ($kr, $kc) = _find_piece($board, $piece);

 
 

-       # check all pieces for the possibility of threatening the two kings
+       # check all pieces for the possibility of threatening this king

        for my $row (0..7) {
                for my $col (0..7) {
                        my $piece = $board->[$row][$col];
                        next if ($piece eq '-');
        for my $row (0..7) {
                for my $col (0..7) {
                        my $piece = $board->[$row][$col];
                        next if ($piece eq '-');

-               
-                       if (uc($piece) eq $piece) {
-                               # white piece
-                               $black_check = 1 if ($board->can_reach($piece, $row, $col, $bkr, $bkc));
-                       } else {
-                               # black piece
-                               $white_check = 1 if ($board->can_reach($piece, $row, $col, $wkr, $wkc));
-                       }
+                       return 1 if ($board->can_reach($piece, $row, $col, $kr, $kc));

                }
        }
 
                }
        }
 

-       if ($black_check && $white_check) {
-               return 'both';
-       } elsif ($black_check) {
-               return 'black';
-       } elsif ($white_check) {
-               return 'white';
-       } else {
-               return 'none';
-       }
+       return 0;

 }
 
 }
 

-sub _find_kings {
-       my $board = shift;
-       my ($wkr, $wkc, $bkr, $bkc);
+sub _find_piece {
+       my ($board, $piece) = @_;

 
        for my $row (0..7) {
 
        for my $row (0..7) {

-               next unless grep { $_ eq 'K' || $_ eq 'k' } @{$board->[$row]};
+               next unless grep { $_ eq $piece } @{$board->[$row]};

                for my $col (0..7) {
                for my $col (0..7) {

-                       my $piece = $board->[$row][$col];
-                       if ($piece eq 'K') {
-                               ($wkr, $wkc) = ($row, $col);
-                       } elsif ($piece eq 'k') {
-                               ($bkr, $bkc) = ($row, $col);
+                       if ($board->[$row][$col] eq $piece) {
+                               return ($row, $col);

                        }
                }
        }
 
                        }
                }
        }
 

-       return ($wkr, $wkc, $bkr, $bkc);
+       return (undef, undef);

 }
 
 }
 

-# Returns if any side is in mate.
+# Returns if the given side (given as k or K) is in mate.

 sub in_mate {
 sub in_mate {

-       my ($board, $check) = @_;
-       return 0 if ($check eq 'none');
+       my ($board, $side, $in_check) = @_;
+       return 0 if (!$in_check);

 
        # try all possible moves for the side in check
        for my $row (0..7) {
 
        # try all possible moves for the side in check
        for my $row (0..7) {


@@ -403,7 +379,7 @@ sub in_mate {
                        my $piece = $board->[$row][$col];
                        next if ($piece eq '-');
 
                        my $piece = $board->[$row][$col];
                        next if ($piece eq '-');
 

-                       if ($check eq 'white') {
+                       if ($side eq 'K') {

                                next if ($piece eq lc($piece));
                        } else {
                                next if ($piece eq uc($piece));
                                next if ($piece eq lc($piece));
                        } else {
                                next if ($piece eq uc($piece));


@@ -414,11 +390,8 @@ sub in_mate {
                                        next if ($row == $dest_row && $col == $dest_col);
                                        next unless ($board->can_reach($piece, $row, $col, $dest_row, $dest_col));
 
                                        next if ($row == $dest_row && $col == $dest_col);
                                        next unless ($board->can_reach($piece, $row, $col, $dest_row, $dest_col));
 

-                                       my $nb = $board->clone();
-                                       $nb->[$row][$col] = '-';
-                                       $nb->[$dest_row][$dest_col] = $piece;
-                                       my $new_check = $nb->in_check();
-                                       return 0 if ($new_check ne $check && $new_check ne 'both');
+                                       my $nb = $board->make_move($row, $col, $dest_row, $dest_col);
+                                       return 0 if (!$nb->in_check($side));

                                }
                        }
                }
                                }
                        }
                }


@@ -434,10 +407,13 @@ sub prettyprint_move {
        my $pretty = $board->_prettyprint_move_no_check_or_mate($from_row, $from_col, $to_row, $to_col, $promo);
 
        my $nb = $board->make_move($from_row, $from_col, $to_row, $to_col, $promo);
        my $pretty = $board->_prettyprint_move_no_check_or_mate($from_row, $from_col, $to_row, $to_col, $promo);
 
        my $nb = $board->make_move($from_row, $from_col, $to_row, $to_col, $promo);

-       my $check = $nb->in_check();
-       if ($nb->in_mate($check)) {
+
+       my $piece = $board->[$from_row][$from_col];
+       my $other_side = (uc($piece) eq $piece) ? 'k' : 'K';
+       my $in_check = $nb->in_check($other_side);
+       if ($nb->in_mate($other_side, $in_check)) {

                $pretty .= '#';
                $pretty .= '#';

-       } elsif ($check ne 'none') {
+       } elsif ($in_check) {

                $pretty .= '+';
        }
        return ($pretty, $nb);
                $pretty .= '+';
        }
        return ($pretty, $nb);